{ "generated_at": "2026-08-17T03:20:07.388Z", "count": 357, "manuals": [ { "slug": "al-aldot-drainage", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/al-aldot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/al-aldot-drainage.json", "document_metadata": { "jurisdiction_name": "Alabama", "jurisdiction_level": "state", "state_code": "AL", "document_title": "ALDOT Hydraulic Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "ALDOT Hydraulic Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "ease the water surface elevation of the 100-year flood to more than the local ordinance requirement at any point within the comm", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "............................... 4-8 The Rational Method ........................................................................", "page_or_section": null }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Use of graded course (porous pavements)", "page_or_section": "August 2018 6-7 / Section 6 Pavement Drainage" }, { "field": "practice_mentions.swale", "excerpt": "Grass channels and filter strips would be examples of LID/GI BMPs", "page_or_section": "August 2018 9-35 / Section 9.3" }, { "field": "practice_mentions.wet_pond", "excerpt": "natural ponds, detention ponds, and water quality ponds that contain water over 24 inches deep", "page_or_section": "August 2018 9-37 / Section 9.4" }, { "field": "practice_mentions.extended_detention", "excerpt": "ED Extended Detention", "page_or_section": "Appendix A Acronyms" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "wetland restoration projects, often referred to as wetland mitigation", "page_or_section": "August 2018 10-9 / Section 10.4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. ALDOT Hydraulic Manual (Draft) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.dot.state.al.us/publications/Design/pdf/HydraulicManualDraft.pdf", "landing_page_url": "https://www.dot.state.al.us/publications/Design/HydraulicResources.html", "retrieved_at": "2026-08-11T17:59:10.548Z", "original_filename": "al-aldot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:20:36.042Z", "enrich_model": "composer-2.5:run-6d67bb98-9d16-448f-8dac-6ebb00d45740", "enrich_notes": "Provided excerpts are largely hydraulic manual (culverts, pavement drainage, regulations). Chapter 9 post-development BMP selection points to external ALDOT Design Bureau Stormwater website for BMP design details. Infeasibility cites soil K less than 1e-4 cm/s. Safety: fencing when pools hold water over 24 inches deep more than 48 hours; clear-zone BMPs should hold less than 2 ft during design/check storm. No explicit WQv depth, drawdown times, SHWT separation, or facility sizing parameters in corpus.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "alabama-handbook", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/alabama-handbook/", "data_url": "https://stormwateratlas.com/data/manuals/alabama-handbook.json", "document_metadata": { "jurisdiction_name": "Alabama", "jurisdiction_level": "state", "state_code": "AL", "document_title": "Erosion Control, Sediment Control and Stormwater Management on Construction Sites and Urban Areas (The Blue Book)", "version_or_edition": "July 2022, Volume 1, Revision No. 5", "adoption_or_effective_date": "2022-07", "last_revised_date": "2022-07", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "First-flush capture: the first 1 inch of runoff carries 90% of the pollution load from a storm (USGS, 1984); detention storage volume can be tied to a first flush capture of the initial 0.1 to 1 inch of runoff, with basin drawdown times of 30–40 hours for pollutant removal.", "peak_flow_calculation_method": [ "NRCS runoff curve number (RCN) method", "Rational method", "TR-55, Urban Hydrology for Small Watersheds" ], "required_hydrologic_hydraulic_software": [ "USDA-NRCS Engineering Field Tools (EFT)" ], "approved_bmp_categories": [ "Site Preparation", "Surface Stabilization", "Runoff Conveyance", "Sediment Control", "Stormwater Management", "Stream Protection", "Bioretention Area", "Porous Pavement", "Stormwater Detention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Alabama Soil and Water Conservation Committee", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "in the State of Alabama", "page_or_section": "Page ix, Introduction" }, { "field": "document_metadata.state_code", "excerpt": "Montgomery, Alabama", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Erosion Control, Sediment Control and Stormwater Management on Construction Sites and Urban Areas (The Blue Book)", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Volume 1... 2022... This major revision No. 5 of July 2022", "page_or_section": "Title Page; Page ix" }, { "field": "document_metadata.last_revised_date", "excerpt": "A concerted effort has been made to make the July 2022 Blue Book an accurate and comprehensive handbook", "page_or_section": "Page i, Foreword" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Alabama Handbook for Erosion Control, Sediment Control and Stormwater Management on Construction Sites and Urban Areas (The Blue Book)", "page_or_section": "Page ix" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Temporary Construction Areas 2-year... Building Sites 5-year... Agricultural Land 10-year... Isolated Buildings 25-year... Urban areas, Residential, School, Industrial Areas, etc. 50-year", "page_or_section": "Page 181, Table DV-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The emergency spillway should be designed to pass at least the l00-year storm.", "page_or_section": "Page 13, Chapter 2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "the first flush equates to the first 1\" of runoff which carries 90% of the pollution load from a storm (USGS, 1984)", "page_or_section": "Page 9, Chapter 2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required storage volume of detention facilities can be tied to a first flush capture (i.e., the initial 0.1\" to 1\" of runoff).", "page_or_section": "Page 12, Chapter 2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The peak rate of runoff should be determined using the Natural Resources Conservation Service runoff curve number (RCN) method or other equivalent methods.", "page_or_section": "Page 181, Diversion" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational method - A means of computing storm drainage flow rates, Q, by use of the formula", "page_or_section": "Glossary" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "TR-55, Urban Hydrology for Small Watersheds", "page_or_section": "References" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Software for the design of a diversion can be found in the USDA-NRCS Engineering Field Tools (EFT).", "page_or_section": "Page 183, Diversion" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "3) modification of the surface drainage pattern, including the associated development of stormwater management facilities. Summary of Hazards Associated with Land Development On-site Land development clearly increases potential erosion and sediment hazards on-sit", "page_or_section": "pp. 18–19" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Area (BA)... Porous Pavement (PP)... Stormwater Detention Basin (SDB)", "page_or_section": "Table of Contents, Page viii" }, { "field": "fields_not_found", "excerpt": "to control volume of the first flush (first ½ inch to 1 inch) runoff.", "page_or_section": "p33" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "It is believed that basin drawdown times between 30-40 hours will result in significant pollutant removal.", "page_or_section": "Chapter 2, page 25" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A distance of 2 feet between the bottom of the bioretention basin and the seasonal high-water table is recommended.", "page_or_section": "Bioretention Area Design Criteria, page 309" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The planting soil layer should have a minimum depth of 2 feet.", "page_or_section": "Bioretention Area Facility Specifications, page 310" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The planned ponding depth above the facility bottom should be 6 inches.", "page_or_section": "Bioretention Area Facility Specifications, page 310" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Wherever possible, sites should have a minimum length to width ratio of 2:1.", "page_or_section": "Bioretention Area Facility Specifications, page 310" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "In-situ soils should have an infiltration rate greater than 1\" per hour for a no-underdrain bioretention area design.", "page_or_section": "Bioretention Area Design Criteria, page 309" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The required storage volume of detention facilities can be tied to a first flush capture (i.e., the initial 0.1\" to 1\" of runoff).", "page_or_section": "Chapter 2, page 25" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The stone reservoir should be designed so that it can be drained within 72 hours", "page_or_section": "Porous Pavement Stone Reservoir, page 305" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://alabamasoilandwater.gov/wp-content/uploads/2022/08/20220801_HandBook_Vol_1.pdf", "landing_page_url": "https://alabamasoilandwater.gov/alesc-bluebook/", "retrieved_at": "2026-08-08T00:55:00.000Z", "original_filename": "alabama-handbook.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 40, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 1, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:20:57.260Z", "enrich_model": "composer-2.5:run-0e83f65b-d234-4dda-b223-c584e9a0cf8a", "enrich_notes": "First-flush / WQ storage is tied to initial 0.1 to 1 inch of runoff (Chapter 2); first 1 inch cited for 90% pollution load (USGS). NPS control cites basin drawdown 30–40 hours for pollutant removal. Bioretention: 2 ft SHWT separation, 2 ft planting soil, 6 in ponding, L:W ≥ 2:1, in-situ infiltration > 1 in/hr for no-underdrain. Porous pavement stone reservoir must drain within 72 hours; SHWT below reservoir bottom (no inch separation stated). Grass swale excerpt gives 0.25 ft freeboard and <1% slope exception, not bottom width or design longitudinal slope.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fremont-ca", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fremont-ca/", "data_url": "https://stormwateratlas.com/data/manuals/fremont-ca.json", "document_metadata": { "jurisdiction_name": "Alameda Countywide Clean Water Program (ACCWP) / City of Fremont", "jurisdiction_level": "special_district", "state_code": "CA", "document_title": "C.3 Stormwater Technical Guidance", "version_or_edition": "Version 8.2 (May 19, 2024)", "adoption_or_effective_date": "2024-05-19", "last_revised_date": "2024-05-19", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "MRP Provision C.3 LID treatment: volume-based sizing (WEF/ASCE 80% capture / related methods) or flow-based sizing using 85th percentile rainfall intensity; biotreatment/bioretention preferred. Hydromodification management (Provision C.3.g) via flow duration control / BAHM where applicable.", "peak_flow_calculation_method": [ "Volume-based BMP sizing (Section 7.1.1 / Appendix C worksheet)", "Flow-based treatment sizing (85th percentile intensity)", "Hydromodification management / BAHM flow duration control (Chapter 9)" ], "required_hydrologic_hydraulic_software": [ "BAHM (Bay Area Hydrology Model)" ], "approved_bmp_categories": [ "Bioretention / bioinfiltration", "Biotreatment measures", "Treatment trains", "Hydromodification management measures", "LID site design / source controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "C.3 Stormwater Technical Guidance / Alameda", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Clean Water Program / MRP municipalities", "page_or_section": "Introduction" }, { "field": "document_metadata.state_code", "excerpt": "California / Municipal Regional Permit", "page_or_section": "Introduction" }, { "field": "document_metadata.document_title", "excerpt": "C.3 Stormwater Technical Guidance", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "builders, and project applicants Version 8.2 MEMBER AGENCIES: Alameda Albany Berkeley Dublin Emeryville Fremont Hayward Livermore Newark Oakland Piedmont Pleasanton San Leandro Union City County of Alameda Alameda County Flood Control and Water Conservation District Zone 7", "page_or_section": "p. 1" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "May 19, 2024", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "May 19, 2024", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "MRP Provision C.3", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "85th percentile value / Volume-based BMP sizing criteria and 80 percent capture", "page_or_section": "Section 7.1 / glossary" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Hydromodification Management / Flow Duration Control / BAHM", "page_or_section": "Chapter 9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention/BioInfiltration Area", "page_or_section": "Section 8.1" }, { "field": "max_drawdown_hours", "excerpt": "Treatment measures should drain completely within 72 hours to effectively suppress mosquito production", "page_or_section": "Chapter 10 / page 147" }, { "field": "max_drawdown_hours", "excerpt": "so that the bioretention area empties over two days", "page_or_section": "Section 8.1 / page 92" }, { "field": "shwt_separation_inches", "excerpt": "If there is at least a 5-foot separation between the bottom of the facility and the seasonal high groundwater level", "page_or_section": "Section 8.1 / page 96" }, { "field": "shwt_separation_inches", "excerpt": "There should be at least a 10-foot separation between the bottom of the trench and the seasonal high groundwater level", "page_or_section": "Section 8.4 / page 113" }, { "field": "bioretention_media_depth_min_inches", "excerpt": "The BSM layer should be at least 18 inches deep.", "page_or_section": "Section 8.1 / page 96" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "filters through the biotreatment soil at a rate of 5 inches per hour (the design surface loading rate for bioretention facilities)", "page_or_section": "Section 7.1.3 / page 73" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "A long-term minimum percolation rate of 5 inches per hour is required", "page_or_section": "Section 8.1 / page 96" }, { "field": "ed_drain_time_hours", "excerpt": "detain the stormwater runoff from a water quality design storm for a minimum of 48 hours", "page_or_section": "Glossary / page 9" }, { "field": "ed_drain_time_hours", "excerpt": "sized to capture the required water quality volume over at least a 48-hour period", "page_or_section": "Section 8.5 / page 116" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "ACCWP C.3 TG v8.2; covers Fremont and other Alameda County MRP cities (aliases). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://cleanwaterprogram.org/wp-content/uploads/2024/05/C3TG-8.2-compiled-20240519.pdf", "landing_page_url": "https://cleanwaterprogram.org/businesses/development/", "retrieved_at": "2026-08-10T08:34:54.567Z", "original_filename": "fremont-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:22:18.160Z", "enrich_model": "composer-2.5:run-1f038c9c-c6be-477c-bdc4-8d9872caaae0", "enrich_notes": "WQv is volume-based (WEF/ASCE); bioretention ponding recommended 6–12 in (Ch 7); native soil min often 0.5 in/hr (trenches, pervious); infiltration trench SHWT min 10 ft (120 in); bioretention empties over two days (~48 h); glossary bioinfiltration references 1.6 in/hr in situ conductivity threshold.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ak-dot-drainage", "processed_at": "2026-08-17T03:19:55.590Z", "detail_url": "https://stormwateratlas.com/ak-dot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ak-dot-drainage.json", "document_metadata": { "jurisdiction_name": "Alaska", "jurisdiction_level": "state", "state_code": "AK", "document_title": "Alaska Highway Drainage Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Alaska Highway Drainage Manual", "page_or_section": "Title / header" }, { "field": "design_parameters", "excerpt": "Alaska Highway Drainage Manual", "page_or_section": "pages 1-2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. Alaska Highway Drainage Manual — cover/TOC chapter proxy (manual is chaptered PDFs) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://dot.alaska.gov/stwddes/desbridge/assets/pdf/hwydrnman/hwydrncover.pdf", "landing_page_url": "https://dot.alaska.gov/stwddes/desbridge/hwy_drainage_manual.shtml", "retrieved_at": "2026-08-11T17:59:10.606Z", "original_filename": "ak-dot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T07:18:57.308Z", "enrich_model": "composer-2.5:run-31d78ea0-3a4e-4425-93d8-93abc8cb6622", "enrich_notes": "Provided corpus is cover/title pages only (Alaska Highway Drainage Manual, pages 1-2); no BMP or design-parameter narrative.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ak-state", "processed_at": "2026-08-17T03:19:55.590Z", "detail_url": "https://stormwateratlas.com/ak-state/", "data_url": "https://stormwateratlas.com/data/manuals/ak-state.json", "document_metadata": { "jurisdiction_name": "Alaska", "jurisdiction_level": "state", "state_code": "AK", "document_title": "Alaska Storm Water Guide", "version_or_edition": "December 2011", "adoption_or_effective_date": "2011-12", "last_revised_date": "2011-12", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 100 ], "water_quality_volume_method": "Treat runoff from 90% of average-year storms (goal: 80% average annual post-development TSS reduction). WQv = (Rv) × (A) × (P) / 12, where P is the 90% cumulative frequency rainfall depth (~0.5–1.25 in by climatic region; Table 2-4). Where end-of-season snowmelt volume exceeds the 90% rainfall volume, size BMPs on meltwater instead.", "peak_flow_calculation_method": [ "Rational Method", "TR-55 (USDA 1986)", "WinTR-20 / SCS methods", "HEC-HMS", "EPA SWMM" ], "required_hydrologic_hydraulic_software": [ "ILLUDAS", "TR55-1986", "WinTR55", "WinTR20 SCS", "HEC-HMS" ], "approved_bmp_categories": [ "Wet Pond", "Extended Storage Pond / Dry ED Ponds", "Dry Pond", "Wet Vaults", "Oil/Grit Separator", "Dry Swale / Wet Swale", "On-Lot Infiltration", "Infiltration Basin", "Infiltration Trench", "Storm Water Wetland / Constructed Wetlands", "Surface Sand Filters / Underground Filters / Filtering Practices", "Bioretention", "Filter Strips", "Green Roofs", "Rain Tank/Cistern", "Permeable Pavers", "Erosion and Sediment Control BMPs", "Good Housekeeping BMPs", "Low Impact Development / Environmental Site Design" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Alaska Department of Environmental Conservation Division of Water", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This Guide was developed with support of a technical workgroup under the direction of the Alaska Department of Environmental Conservation.", "page_or_section": "Preface, page i" }, { "field": "document_metadata.state_code", "excerpt": "Anchorage, Alaska 99501", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Alaska Storm Water Guide December 2011", "page_or_section": "Title Page / running header" }, { "field": "document_metadata.version_or_edition", "excerpt": "December 2011", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "December 2011", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Alaska Storm Water Guide December 2011", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The concepts presented in this Guide are intended to be guidance for readers rather than stringent rules.", "page_or_section": "Preface, page i" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1-year, 24-hour duration storm event... Provide peak discharge control of the 5-year storm event... Some jurisdictions may require peak discharge control for the 2-year storm event... Evaluate the effects of the 100-year storm", "page_or_section": "Table 3-4, Unified sizing criteria, Section 3.3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat the runoff from 90% of the storms that occur in an average year. For Alaska, this equates to providing water quality treatment for the runoff resulting from a rainfall depth of 1.25 inches or less. The goal is to reduce average annual post-development TSS loadings by 80%. WQv = (Rv) × (A) × (P) / 12", "page_or_section": "Table 3-4; Section 3.3.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The rainfall depth associated with the 90 percent storm varies geographically across Alaska, but it typically ranges between 0.5 and 1.25 inches.", "page_or_section": "Chapter 2, page 2-9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "A partial list of hydrologic modeling software accepted by some Alaskan municipalities includes the following: ILLUDAS TR55-1986 WinTR553 WinTR20 SCS HEC-HMS Rational Method", "page_or_section": "Section 3.2, page 3-5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Soil Conservation Service methods including TR-55... EPA SWMM", "page_or_section": "Accepted Analytical Methods for Assessing Channel Protection / Flood Potential" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "A partial list of hydrologic modeling software accepted by some Alaskan municipalities includes the following: ILLUDAS TR55-1986 WinTR553 WinTR20 SCS HEC-HMS", "page_or_section": "Section 3.2, page 3-5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Primary Secondary Secondary Secondary Extended Storage Pond High Low Primary Secondary Secondary Secondary Wet Vaults Medium Lowa Primary Secondary Secondary Minor Detention Dry Pond High Low Secondary Minor Minor Minor Oversized Pipes High Low Minor Minor Minor Minor Oil/Grit", "page_or_section": "pp. 180–181" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1-year, 24-hour duration storm event", "page_or_section": "Table 3-4 Unified sizing criteria, pages 78-79" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green roofs can be installed on building roofs with slopes up to 25 percent.", "page_or_section": "Green Roof Design Adaptation for Alaska, page 200" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = design rainfall depth (90% cumulative frequency depth) (~ 0.5 to 1.25 inches)", "page_or_section": "Table 3-4, pages 78-79" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention cells, commonly known as rain gardens, are relatively small-scale, landscaped depressions", "page_or_section": "Section 5.2 LID, page 182" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry ED Ponds", "page_or_section": "Table 5-2, page 185" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "demonstrate that the proposed oil and grit separator(s) has (have) the ability to remove at least 50 percent of TSS particles larger than 20 microns", "page_or_section": "Chapter 1, page 31" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Statewide guidance (not binding code). Hydrologic software listed is accepted by some municipalities, not a statewide mandate. Unified sizing criteria and regional WQv depths are recommendations; local ordinances (e.g., Anchorage) may differ. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://plants.alaska.gov/pdf/akswguide.pdf", "landing_page_url": "https://plants.alaska.gov/", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "ak-state.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 25, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:19:20.432Z", "enrich_model": "composer-2.5:run-8ec1dec9-a739-4844-b9b0-6fe2e15bbc88", "enrich_notes": "WQv uses regional 90% storm or end-of-season snowmelt depth (examples: 1.25 in coastal rainfall, 0.5 in interior rainfall, 1.2 in interior meltwater; Table 3-4 cites ~0.5–1.25 in and up to 1.25–1.75 in in wet climates). Channel protection Cpv requires 24 h extended detention of 1-year, 24-hour runoff. Soil infiltration classes: high ≥0.5 in/hr, moderate 0.1–0.5 in/hr, low <0.1 in/hr; extreme-design note gives acceptable infiltration 1–4 in/hr for high-rainfall infiltration. Bioretention Alaska adaptations include 12 in filter depth with 9 in underdrain layer under permafrost extreme design. Infiltration: 25 ft setback from roadways/foundations; excavation not within 3 ft of permafrost. Wet pond: low-flow orifice at least 6 in below typical ice layer; minimum 1% pipe slope.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "az-adot-drainage", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/az-adot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/az-adot-drainage.json", "document_metadata": { "jurisdiction_name": "Arizona Department of Transportation (ADOT)", "jurisdiction_level": "state", "state_code": "AZ", "document_title": "Highway Drainage Design Manual — Hydrology (Volume 2)", "version_or_edition": "Second Edition, 2014", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "HEC-HMS" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [ "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Arizona Department of Transportation (ADOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Highway Drainage Design Manual — Hydrology (Volume 2)", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "...... 11-6 Figure 11-5 Data Points and 100-year Peak Discharge Relation for R1 .................................... 11-7 Figure", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "s. The two analytic methods are: 1. The Rational Method. Used for uniform drainage areas that are less than 160 acres in size. 2", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Basin", "page_or_section": null } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. ADOT Highway Drainage Design Manual Vol 2 Hydrology (2014). Companion Hydraulics volume also available.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://azdot.gov/sites/default/files/2019/07/2014_adot_hydrology_manual.pdf", "landing_page_url": "https://azdot.gov/business/engineering-and-construction/roadway-engineering/drainage-design/manuals-drainage-design", "retrieved_at": "2026-08-11T17:21:06.007Z", "original_filename": "az-adot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T07:31:34.900Z", "enrich_model": "composer-2.5:run-4e49d42e-7bb5-4b0b-834b-0001225de8da", "enrich_notes": "Provided excerpts are ADOT Highway Drainage Design Manual Volume 2 — Hydrology (2014): rainfall (NOAA Atlas 14), Rational Method, rainfall losses, unit hydrographs, channel/storage routing, transmission losses, and HEC-HMS/FLO-2D modeling. No stormwater BMP or water-quality treatment design chapter content appears in the corpus; numeric SCM parameters are not stated. Hydraulics and policy volumes may contain BMP guidance elsewhere.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "arlington-county-va", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/arlington-county-va/", "data_url": "https://stormwateratlas.com/data/manuals/arlington-county-va.json", "document_metadata": { "jurisdiction_name": "Arlington County", "jurisdiction_level": "county", "state_code": "VA", "document_title": "Stormwater Manual: A Guide to Stormwater Requirements for Land Disturbing Activities in Arlington County", "version_or_edition": "July 2025", "adoption_or_effective_date": "2025-07-01", "last_revised_date": "2025-07-01", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Water quality technical criteria aligned with VADEQ Stormwater Management Handbook / Virginia Runoff Reduction Method (VRRM) and Virginia BMP Clearinghouse. County clarifications for BMPs, underdrains, setbacks, waterproofing, and soil/infiltration testing. Energy-balance detention used for water quantity / flood control where applicable.", "peak_flow_calculation_method": [ "Virginia Runoff Reduction Method (VRRM)", "Energy balance detention / water quantity worksheet", "Virginia Stormwater BMP Clearinghouse design specs" ], "required_hydrologic_hydraulic_software": [ "VRRM spreadsheet" ], "approved_bmp_categories": [ "Virginia BMP Clearinghouse SCMs", "Sheetflow to vegetated filter strip / conserved open space", "Detention tanks / energy-balance facilities", "Stormwater planters / urban BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "LAND DISTURBING ACTIVITIES IN ARLINGTON COUNTY", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Arlington County", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANUAL: A GUIDE TO STORMWATER REQUIREMENTS", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Updated for consistency with new VADEQ Stormwater", "page_or_section": "Highlights / §2.2.4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Technical Criteria ... VRRM", "page_or_section": "§2.2.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "energy balance detention for flood control", "page_or_section": "Water quantity" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Modified VRRM spreadsheet", "page_or_section": "TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Virginia Stormwater BMP Clearinghouse", "page_or_section": "Facility Design Considerations" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "provided they are designed to drawdown within 24 hours", "page_or_section": "2.9 Requirements for Single Family Residences Built Separately, page 38" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Obtain Level I permeable pavement credit for pavement designs with the twelve (12) inches of stone storage and no underdrain", "page_or_section": "Section 2.9, page 38" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "in soils that do not percolate at a rate >0.5 inch hour", "page_or_section": "Section 2.9, page 38" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Obtain Level 1 urban bioretention (planter box) credit for designs utilizing only 18\" of soil media", "page_or_section": "Section 2.9, page 38" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The maximum height from the top of mulch elevation to the top of the planter box wall shall not exceed 15 inches", "page_or_section": "Urban Bioretention (Planter Box), page 31" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "PICP: 2 in. depth of No. 8 stone above 4 inches of No. 57", "page_or_section": "Material Specifications for Permeable Pavements, page 24" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "The slope of the surface of the permeable pavement systems shall be from 1 to 10 percent", "page_or_section": "2.2.4 Permeable Pavement, page 22" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention facilities may not be constructed on slopes steeper than 15 percent", "page_or_section": "2.2.4 Bioretention, page 28" }, { "field": "practice_mentions.green_roof", "excerpt": "All of the design specifications are taken from the Handbook 8.31. P-FIL-02", "page_or_section": "Vegetated Roof, page 22" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The maximum length or width of an infiltration trench is 16 feet or less for SFD infill project", "page_or_section": "Infiltration Practices, page 25" }, { "field": "practice_mentions.extended_detention", "excerpt": "2.9.5.3 Detention tanks", "page_or_section": "Alternative Compliance Option, page 44" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "County LDA guidance manual; numeric WQv depths primarily via VRRM/Handbook rather than restated inline. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.arlingtonva.us/files/sharedassets/public/v/3/building/documents/guidance_manual_lda2.0-2025-updates-for-new-vrrm-and-bmp-manual.pdf", "landing_page_url": "https://www.arlingtonva.us/Government/Programs/Building/Permits/Land-Disturbing-Activity-Stormwater/Land-Disturbing-ActivityStormwater-Permit-Details", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "arlington-county-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 15, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement" ], "enriched_at": "2026-08-13T07:27:19.993Z", "enrich_model": "composer-2.5:run-b7bcb5a6-017b-4184-bc38-41cecc7fd7bf", "enrich_notes": "County adopts Virginia Stormwater Management Handbook specs (P-FIL-02 through P-FIL-07) with local clarifications; WQV depths and most BMP sizing are in VRRM/Handbook rather than restated. Level I SFD options: 12 in stone storage permeable pavement with 24 hr drawdown when infiltration ≤0.5 in/hr; Level 1 urban bioretention with 18 in filter media. Permeable pavement surface slope 1–10%, adjacent slopes max 20%; artificial turf/other surfaces require 5 gal/min/ft² acceptance rate.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "athens-ga", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/athens-ga/", "data_url": "https://stormwateratlas.com/data/manuals/athens-ga.json", "document_metadata": { "jurisdiction_name": "Athens-Clarke County", "jurisdiction_level": "municipality", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (Athens-Clarke adopts GSMM)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Athens-Clarke County adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "111" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "Vol 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "Vol 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection, page 120" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via GSMM 2016 (same pattern as Macon/Atlanta). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:39:14.779Z", "original_filename": "athens-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:28:44.428Z", "enrich_model": "composer-2.5:run-9d0861d8-8e53-4932-a3f8-5fadc964626d", "enrich_notes": "GSMM Vol 1 excerpts only; WQv 1.2 in and RRV 1.0 in stated in Standards #3–#4. Channel protection uses 24-hour extended detention of 1-year 24-hour event (Standard #5). Bioretention, permeable pavement, swales, and green roofs appear in Better Site Design; Vol 2 BMP numeric specs not in corpus. Permanent stormwater infiltration basins prohibited in high-susceptibility groundwater recharge areas.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "augusta-ga", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/augusta-ga/", "data_url": "https://stormwateratlas.com/data/manuals/augusta-ga.json", "document_metadata": { "jurisdiction_name": "Augusta", "jurisdiction_level": "municipality", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (Augusta-Richmond adopts GSMM)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Augusta adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "and Flooding (Right Photo Source: Augusta Chronicle / Photo by Cindy Blanchard) Figure 2.1-6 Hydrograph under Pre- and Post-Development Conditions (Source: Schueler, 1992) STREAM FLOW RATE TIME Changes in stream hydrology as a result of urbanization (Schueler, 1992) Pre-dev", "page_or_section": "pp. 20–21" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals... 2-year through the 25-year return frequency storm events", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater management systems shall be designed to retain or treat the runoff from 85% of the storms that occur in an average year, and reduce average annual post-development total suspended solids loadings by 80%. Averaged from rainfall events across the state of Georgia, this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events.", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "What is the SCS curve number for this sub-watershed", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters; Regenerative Stormwater Conveyance; Sand Filters; and Stormwater Planters/Tree Boxes", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "Vol 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "Vol 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The first method of providing stream bank protection is the extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection, page 120" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via GSMM 2016; replace with Augusta-specific manual if a durable public PDF appears. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "augusta-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:29:18.920Z", "enrich_model": "composer-2.5:run-78e79928-e536-4597-acc9-d93b820f0606", "enrich_notes": "Augusta adopts GSMM 2016. WQv = runoff from 1.2 in rainfall (85% of average-year storms); runoff reduction targets first 1.0 in on-site. Channel protection uses 24-hr extended detention of 1-yr 24-hr storm. Corpus is Vol.1 (standards, BSD, O&M); BMP numeric specs referenced to Vol.2 Ch.4 not included in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "albuquerque-nm-gsi", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/albuquerque-nm-gsi/", "data_url": "https://stormwateratlas.com/data/manuals/albuquerque-nm-gsi.json", "document_metadata": { "jurisdiction_name": "Bernalillo County", "jurisdiction_level": "county", "state_code": "NM", "document_title": "Bernalillo County Green Stormwater Infrastructure Low Impact Design Strategies for Desert Communities", "version_or_edition": "March 2025", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Bernalillo County Ordinance 2107-8 requires storm water treatment volumes of 90% storm capture for new development and 80% storm capture for redevelopment within site boundaries; this digest references the Design Process Manual (DPM) for detailed sizing and construction details.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioswale", "Infiltration Trench", "Stormwater Curb Extension", "Raised Median", "Stormwater Tree Pit with Grate", "Stormwater Planter Box", "Pervious Pavement", "Permeable Check Dam", "Stacked Stone Erosion Control Basin (Zuni Bowl)", "Stone Channel Plating", "Contour Swale", "Media Luna Flow Spreader" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "BERNALILLO COUNTY GREEN STORMWATER INFRASTRUCTURE LOW IMPACT DESIGN STRATEGIES FOR DESERT COMMUNITIES", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Bernalillo County approved and implemented Ordinance 2107-8 to address requirements specified in the Watershed Based MS4 permit", "page_or_section": "Recap of BernCo Stormwater Quality Ordinance, Page 9" }, { "field": "document_metadata.state_code", "excerpt": "Bernalillo County location within New Mexico state", "page_or_section": "Context, Page 9" }, { "field": "document_metadata.document_title", "excerpt": "BERNALILLO COUNTY GREEN STORMWATER INFRASTRUCTURE LOW IMPACT DESIGN STRATEGIES FOR DESERT COMMUNITIES", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This document and others like it, while containing useful information regarding the implementation and the benefits of GI/LID interventions, are highly technical and cumbersome making them inaccessible to the general public.", "page_or_section": "Introduction and Purpose, Page 6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "storm water treatment volumes (90% storm for new development, 80% storm for redevelopment) must be addressed within the boundaries of a proposed site development/redevelopment plan", "page_or_section": "Recap of BernCo Stormwater Quality Ordinance, Page 9" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Previously developed guidelines for these practices have been developed for Bernalillo County and the City of Albuquerque such as the Bernalillo County Water Conservation Guidelines and the Design Process Manual (DPM)", "page_or_section": "Introduction and Purpose, Page 6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioswale, Infiltration Trench, Stormwater Curb Extension, Raised Median, Stormwater Tree Pit with Grate, Stormwater Planter Box, Pervious Pavement, Permeable Check Dam, Stacked Stone Erosion Control Basin \"Zuni Bowl\", Stone Channel Plating, Contour Swale, Media Luna Flow Spreader", "page_or_section": "Table of Contents, Pages 4-5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Requires permeable soils for infiltration in under 96 hours.", "page_or_section": "Glossary / Infiltration Trench, page 26" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Intended to release water into the soil within 96 hours.", "page_or_section": "Glossary / Passive Rainwater Harvesting, page 26" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of trench should be at least 3' above seasonal high water table", "page_or_section": "Infiltration Trench 3.0 DPM DETAIL 3.0, page 9" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If native soils have a minimum infiltration rate of < 0.1 inches per hour, supplemental drainage systems may be required.", "page_or_section": "Pervious Pavement DPM DETAIL 9.0, page 18" }, { "field": "practice_mentions.swale", "excerpt": "Bioswales are linear stormwater management features used to convey, slow, and treat runoff", "page_or_section": "Bioswale 1.0, page 7" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "TYPE 2 INFILTRATION TRENCH CONCENTRATED INLET", "page_or_section": "Infiltration Trench 3.0, page 9" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Pervious pavement refers to a wide variety of surfaces... that effectively treat, detains, and infiltrates stormwater runoff", "page_or_section": "Pervious Pavement 9.0, page 18" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention See 'Bioinfiltration.' which is more accurate for a New Mexico context.", "page_or_section": "Glossary DPM DETAIL 14.0, page 25" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Abbreviated GSI/LID digest for arid-climate implementation; references Bernalillo County Ordinance 2107-8 and DPM for quantitative design but does not include peak-flow methods, hydrologic software, or detailed storm sizing equations. Edition inferred from source PDF URL (March 2025). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://swefc.unm.edu/gardb/wp-content/uploads/2025/03/61-Green_Infrastructure_and_Low_Impact_Design_Guide_1-1.pdf", "landing_page_url": "https://www.bernco.gov/", "retrieved_at": "2026-08-08T01:05:00.000Z", "original_filename": "albuquerque-nm-gsi.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.1, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:22:26.204Z", "enrich_model": "composer-2.5:run-85904939-74e1-4cc6-9008-a89d215ceb5b", "enrich_notes": "Bernalillo County GSI digest emphasizes desert bioinfiltration (bioswales/rain gardens) with supplemental irrigation; quantitative WQV sizing deferred to Ordinance 2107-8 and DPM. Infiltration practices reference 96-hour drawdown/infiltration timing and 3 ft SHWT clearance for trenches. Permeable pavement cites 0.1 in/hr native soil threshold for supplemental drainage; base/sub-base layer mins (4 in, 6 in) are separate components, not a single storage depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "boston-ma", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/boston-ma/", "data_url": "https://stormwateratlas.com/data/manuals/boston-ma.json", "document_metadata": { "jurisdiction_name": "Boston Water and Sewer Commission", "jurisdiction_level": "municipality", "state_code": "MA", "document_title": "2024 Stormwater Management Report", "version_or_edition": "2024", "adoption_or_effective_date": null, "last_revised_date": "2024", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "On-site retention/infiltration mandatory for all development or redevelopment: infiltrate a volume equal to 1 inch of rainfall × total impervious area for projects under 100,000 sf floor area; 1.25 inches of rainfall × total impervious area for projects at or above 100,000 sf floor area, prior to discharge to storm drain or combined sewer. Report states on-site infiltration removes total suspended solids but does not specify a TSS percent-removal target. Consent Decree BMP Recommendations Report also continues requiring priority BMPs to treat 1-inch of runoff from the site before MS4 discharge.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "On-site retention / infiltration devices", "Particle separators / grit separators (parking and paved outdoor areas)", "Green infrastructure / LID (bioretention, vegetative swales, infiltration basins, permeable pavers)", "Subsurface gravel filters", "Construction site structural and non-structural BMPs (SWPPP)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Boston Water & Sewer Commission 2024 Stormwater Management Report", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Discharges to the Boston Water and Sewer Commission’s (Commission) municipal separate storm sewer system (MS4)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "Massachusetts Department of Environmental Protection (DEP)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.document_title", "excerpt": "2024 Stormwater Management Report", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2024 Stormwater Management Report", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "2024 Stormwater Management Report", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This requirement is consistent with the Department of Environmental Protection’s Stormwater Management Policy which establishes standards for stormwater management for development, and the Commission’s Stormwater BMP Guidance document.", "page_or_section": "Section 3.5 / Section 7.5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "A volume of runoff equal to one inch of rainfall multiplied by the total impervious area on site must be infiltrated prior to discharge to a storm drain or a combined sewer system for projects less than 100,000 square feet of floor area. For all projects which are at or above 100,000 square feet of floor area, the project must use a volume of runoff equal to 1.25 inches of rainfall multiplied by the total impervious area on site.", "page_or_section": "Section 3.5 On-site Retention of Stormwater, Pages 3-7 to 3-8" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "On-site infiltration of stormwater serves to limit peak discharge rates, recharge groundwater, and remove total suspended solids in the flow.", "page_or_section": "Section 3.5, Page 3-8" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "continue to require new development and redevelopment projects to incorporate priority BMPs with high pollutant removal rates to treat 1-inch of runoff from the site prior to discharging into the Commission’s MS4.", "page_or_section": "Section 4.3 BMP Recommendations Report, Page 4-2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "In 2024, the Commission approved installations of 301 infiltration devices.", "page_or_section": "Section 3.5 / Table 3-4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "the Commission may require developers to install particle separators on newly constructed storm drains that serve large outdoor parking areas.", "page_or_section": "Section 3.5 Controls for New Parking Lots, Page 3-8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The Commission requires that developers install grit separators on all newly constructed storm drains that serve outdoor paved areas of 7,500 square feet in size or greater.", "page_or_section": "Section 7.5.b, Page 7-4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "design of bioretention and subservice infiltration along Coolidge Road in Brighton", "page_or_section": "Section 4.6, Page 4-3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "construction site operators, where applicable, are required to use and maintain appropriate structural and non-structural BMPs to minimize the discharge of pollutants from construction sites to the Commission’s MS4.", "page_or_section": "Section 3.5, Page 3-6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A volume of runoff equal to one inch of rainfall multiplied by the total impervious area on site must be infiltrated prior to discharge", "page_or_section": "3.2 SEWER SYSTEM OVERFLOW CONTROL AND RESPONSE, page 27" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For all projects which are at or above 100,000 square feet of floor area, the project must use a volume of runoff equal to 1.25 inches of rainfall multiplied by the total impervious area on site", "page_or_section": "3.2 SEWER SYSTEM OVERFLOW CONTROL AND RESPONSE, page 27" }, { "field": "practice_mentions.bioretention", "excerpt": "rain gardens and vegetative swales, infiltration basins, and paving materials and permeable surfaces", "page_or_section": "4.9 BOSTON COMPLETE STREETS INITIATIVE, page 45" }, { "field": "practice_mentions.swale", "excerpt": "rain gardens and vegetative swales, infiltration basins, and paving materials and permeable surfaces", "page_or_section": "4.9 BOSTON COMPLETE STREETS INITIATIVE, page 45" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "rain gardens and vegetative swales, infiltration basins, and paving materials and permeable surfaces", "page_or_section": "4.9 BOSTON COMPLETE STREETS INITIATIVE, page 45" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "rain gardens and vegetative swales, infiltration basins, and paving materials and permeable surfaces", "page_or_section": "4.9 BOSTON COMPLETE STREETS INITIATIVE, page 45" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "the Commission may require developers to install particle separators on newly constructed storm drains that serve large outdoor parking areas", "page_or_section": "3.2 SEWER SYSTEM OVERFLOW CONTROL AND RESPONSE, page 27" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "This is an annual MS4/Consent Decree program report, not a design criteria manual. On-site retention inches (1.0 / 1.25 in × impervious) and TSS removal as a stated benefit are reported from Site Plan Requirements / Sewer Use Regulations as summarized herein; no design-storm return periods, hydrologic peak-flow methods, required software, or numeric TSS % removal target appear in this document. Prefer BWSC Requirements for Site Plans / Stormwater BMP Guidance for engineering criteria.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.bwsc.org/sites/default/files/2025-02/Stormwater%20Management%20Report%202024.pdf", "landing_page_url": "https://www.bwsc.org/builders-contractors/site-plan-requirements/storm-drain-requirements", "retrieved_at": "2026-08-08T11:41:31.164Z", "original_filename": "boston-ma.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T07:39:27.762Z", "enrich_model": "composer-2.5:run-cb177b5b-866b-4b57-9187-933d1f1801f6", "enrich_notes": "2024 MS4 annual report, not a design manual; references Site Plan Requirements, Sewer Use Regulations, and Stormwater BMP Guidance for engineering criteria. On-site retention uses rainfall depth × impervious area: 1.0 in (<100,000 sf floor area) and 1.25 in (≥100,000 sf)—both explicit on page 27; scalar wqv_depth_inches set to 1.0 as the stated base requirement. No numeric TSS removal target, drawdown, infiltration rate, or SCM sizing dimensions in corpus. Consent Decree context cites treating 1-inch runoff before MS4 discharge (atlas summary).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ca-casqa-municipal", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/ca-casqa-municipal/", "data_url": "https://stormwateratlas.com/data/manuals/ca-casqa-municipal.json", "document_metadata": { "jurisdiction_name": "California", "jurisdiction_level": "state", "state_code": "CA", "document_title": "Stormwater Best Management Practice Handbook — Municipal", "version_or_edition": "January 2003 (Errata 9-04)", "adoption_or_effective_date": "2003-01-01", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Non-Stormwater Management", "Vehicle and Equipment Management", "Material and Waste Management", "Building and Grounds Management", "Over Water Activities", "General Stormwater Management", "Road and Street Maintenance", "Plaza and Sidewalk Cleaning", "Fountains and Pools Maintenance", "Landscape Maintenance", "Drainage System Maintenance", "Water and Sewer Utility Maintenance", "Infiltration Trench", "Infiltration Basin", "Retention/Irrigation", "Wet Pond", "Constructed Wetland", "Extended Detention Basin", "Vegetated Swale", "Vegetated Buffer Strip", "Bioretention", "Media Filter", "Water Quality Inlet", "Multiple Systems", "Manufactured Wetland", "Manufactured Media Filter", "Wet Vault", "Vortex Separator", "Manufactured Drain Inlet" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "California Stormwater Quality Association (CASQA)", "page_or_section": "Acknowledgements, Page 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Contributing agencies include: State Agencies California Department of Transportation California State Water Resources Control Board", "page_or_section": "Acknowledgements, Pages 1-2" }, { "field": "document_metadata.state_code", "excerpt": "January 2003 California Stormwater BMP Handbook", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Best Management Practice Handbook Municipal", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "January 2003 California Stormwater BMP Handbook", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "January 2003 California Stormwater BMP Handbook", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Federal and state programs require selected municipalities to reduce the discharge of pollutants in their stormwater discharges to the maximum extent practicable (MEP) using an array of control measures including BMPs.", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 3-1 Municipal Fixed Facility BMPs: Non-Stormwater Management, Vehicle and Equipment Management, Material and Waste Management, Building and Grounds Management, Over Water Activities, General Stormwater Management", "page_or_section": "Table 3-1, Page 3-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 3-2 Municipal Field Program BMPs: Road and Street Maintenance, Plaza and Sidewalk Cleaning, Fountains & Pools Maintenance, Landscape Maintenance, Drainage System Maintenance, Waste Handling and Disposal, Water and Sewer Utility Maintenance", "page_or_section": "Table 3-2, Page 3-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 4-1 Treatment Control BMPs — Public Domain: Infiltration Trench, Infiltration Basin, Retention/Irrigation, Wet Pond, Constructed Wetland, Extended Detention Basin, Vegetated Swale, Vegetated Buffer Strip, Bioretention, Media Filter, Water Quality Inlet, Multiple Systems", "page_or_section": "Table 4-1, Page 4-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 4-1 Treatment Control BMPs — Manufactured (Proprietary): MP-20 Wetland, MP-40 Media Filter, MP-50 Wet Vault, MP-51 Vortex Separator, MP-52 Drain Inlet", "page_or_section": "Table 4-1, Page 4-1" }, { "field": "practice_mentions", "excerpt": "TC-32 Bioretention", "page_or_section": "p203" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the stormwater runoff from a water quality design storm for some minimum time (e.g., 72 hours) to allow particles and associated pollutants to settle", "page_or_section": "Extended Detention Basin TC-22, page 191/247" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "ensure that the basin dewaters completely (recommended 72 hour residence time or less)", "page_or_section": "Extended Detention Basin TC-22, page 191/247" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "recommended infiltration rate of 72 hours or less", "page_or_section": "TC-11 Infiltration Basin, page 178/234" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "maintain storage capacity within 2/3 of the design treatment volume and 72-hour exfiltration rate limit", "page_or_section": "TC-10 Infiltration Trench, page 174/230" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "whether the facility is draining completely within 72 hr", "page_or_section": "TC-40 Media Filter, page 208/218" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "CASQA Municipal Handbook is an operations and maintenance guidance document for MS4 permittees, not a post-construction design manual. Design requirements for treatment BMPs are deferred to the separate New Development and Redevelopment Handbook.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.casqa.org/wp-content/uploads/2022/12/BMP_Municipal_Complete.pdf", "landing_page_url": "https://www.casqa.org/resources/bmp-handbooks/municipal-bmp-handbook", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "ca-casqa-municipal.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:44:36.276Z", "enrich_model": "composer-2.5:run-28b94601-9ede-48f2-befc-12e49b2016eb", "enrich_notes": "CASQA Municipal Handbook Section 4 is inspection and maintenance only; design requirements are deferred to the New Development and Redevelopment BMP Handbook. Explicit numerics in excerpts are mostly 72-hour drain, residence, or exfiltration limits used as O&M performance checks. TC-40 media filter maintenance cites 18 in. and 12 in. overall media depths and 2 in. surface removal—not mapped to bioretention filter media design fields.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ca-caltrans-construction", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/ca-caltrans-construction/", "data_url": "https://stormwateratlas.com/data/manuals/ca-caltrans-construction.json", "document_metadata": { "jurisdiction_name": "California Department of Transportation (Caltrans)", "jurisdiction_level": "state", "state_code": "CA", "document_title": "Construction Site Best Management Practices (BMP) Manual", "version_or_edition": "March 2024 (CTSW-RT-24-425.11.1)", "adoption_or_effective_date": "2024-03-01", "last_revised_date": "2024-03-01", "relationship_to_state_manual": "adopts_state_manual_directly", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Revised Universal Soil Loss Equation v2 (RUSLE2)" ], "required_hydrologic_hydraulic_software": [ "RUSLE2" ], "approved_bmp_categories": [ "Temporary Soil Stabilization", "Temporary Sediment Control", "Wind Erosion Control", "Tracking Control", "Non-Stormwater Management", "Waste Management and Materials Pollution Control", "Biofiltration Systems", "Design Pollution Prevention Infiltration Areas", "Infiltration Devices", "Detention Devices", "Traction Sand Traps", "Dry Weather Flow Diversion", "Full-capture Trash Devices", "Media Filters", "Multi-chamber Treatment Train", "Wet Basins", "Bioretention", "Open Graded Friction Course", "Porous Pavement" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "California Department of Transportation Division of Environmental Analysis, Storm Water Program", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "California Department of Transportation", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Sacramento, California 95814", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Construction Site Best Management Practices (BMP) Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "March 2024 CTSW-RT-24-425.11.1", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Report Date: March 2024", "page_or_section": "Caltrans Technical Report Documentation Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Report Date: March 2024", "page_or_section": "Caltrans Technical Report Documentation Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "construction projects with 1 acre or more of soil disturbance to comply with the CGP Order WQ 2022-0057-DWQ and amendments thereto", "page_or_section": "Section 1.2.2, Page 1-2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "A 2-year, 24-hour storm event has been used by many as a default event, but recent studies have shown that this may oversize the system", "page_or_section": "Section 7.1.5 NS-5 Clear Water Diversion, Page 7-5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The equivalent sediment load may be calculated using the Revised Universal Soil Loss Equation, version 2 (RUSLE2) or another method approved by the Regional Water Board.", "page_or_section": "Section 2.3.1 Surface Water Buffers, Page 2-7" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "calculated using the Revised Universal Soil Loss Equation, version 2 (RUSLE2)", "page_or_section": "Section 2.3.1 Surface Water Buffers, Page 2-7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Caltrans Construction Site BMPs are divided into six categories, as shown in Table 2-1: Temporary Soil Stabilization, Temporary Sediment Control, Wind Erosion Control, Tracking Control, Non-Stormwater Management, Waste Management and Materials Pollution Control", "page_or_section": "Section 2.2, Table 2-1, Pages 2-5 to 2-7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 10-1. Approved TBMPs: Biofiltration Systems, Design Pollution Prevention Infiltration Areas, Infiltration Devices, Detention Devices, Traction Sand Traps, Dry Weather Flow Diversion, Full-capture Trash Devices, Media Filters, Multi-chamber Treatment Train, Wet Basins, Bioretention, Open Graded Friction Course, Porous Pavement (Non-Highway Facilities Only)", "page_or_section": "Table 10-1, Section 10.2, Page 10-1" }, { "field": "fields_not_found", "excerpt": "based on 0.5 inches of runoff volume over a 24-hour", "page_or_section": "p90" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The water quality outlet should be designed to drain the basin within 24 to 96 hours (also referred to as drawdown time; the 24-hour limit is specified to provide adequate settling time; the 96-hour limit is specified to avoid vector control concerns).", "page_or_section": "SC-2 Sediment/Desilting Basin, pages 82-83" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "With a drawdown time of 40 hours, the equation becomes:", "page_or_section": "SC-2 Sediment/Desilting Basin, page 83" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention • Drain time does not exceed 96 hours after end of rain event", "page_or_section": "Section 10.4 TBMP Maintenance Indicators, page 237" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous Pavement (Non-Highway Facilities Only)", "page_or_section": "Table 10-1 Approved TBMPs, page 233" }, { "field": "practice_mentions.sand_filter", "excerpt": "Drain time does not exceed 72 hours (in the filter chamber for Delaware Sand Filter)", "page_or_section": "Section 10.4 Media Filters, page 237" }, { "field": "practice_mentions.swale", "excerpt": "There is more than 70 percent background coverage of vegetation in swale invert and swale side slope", "page_or_section": "Section 10.4 Biofiltration Systems, page 236" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Construction-phase BMP manual for Caltrans right-of-way projects. Post-construction TBMP sizing and water quality volume methods are in the Project Planning and Design Guide (PPDG), not this manual. RUSLE2 is required for surface-water-buffer equivalency; 2-year storm cited only as a common clear-water-diversion default.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://dot.ca.gov/-/media/dot-media/programs/construction/documents/environmental-compliance/construction-site-bmps_final-march-2024_a11y.pdf", "landing_page_url": "https://dot.ca.gov/programs/construction/storm-water-and-water-pollution-control/manuals-and-handbooks", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "ca-caltrans-construction.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:42:58.530Z", "enrich_model": "composer-2.5:run-e256142f-c55f-4982-acf7-39915d208b44", "enrich_notes": "Construction-phase BMP manual; post-construction TBMP sizing and water-quality volume methods are deferred to the Project Planning and Design Guide (PPDG). Temporary Sediment/Desilting Basin (SC-2) specifies water-quality outlet drawdown between 24 and 96 hours (40 hours used only as an equation example). Section 10 lists approved TBMPs and maintenance drain/standing-water thresholds (often 72 or 96 hours) without design-depth or infiltration-rate criteria in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ca-caltrans-project-planning", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/ca-caltrans-project-planning/", "data_url": "https://stormwateratlas.com/data/manuals/ca-caltrans-project-planning.json", "document_metadata": { "jurisdiction_name": "California Department of Transportation (Caltrans)", "jurisdiction_level": "state", "state_code": "CA", "document_title": "Stormwater Quality Handbooks — Project Planning and Design Guide", "version_or_edition": "June 2023", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5 ], "water_quality_volume_method": "Water Quality Volume (WQV) and Water Quality Flows (WQF)", "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Infiltration Basin", "Infiltration Trench", "Sand Filter", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "California Department of Transportation (Caltrans)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Quality Handbooks — Project Planning and Design Guide", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2, 5-year design storms referenced", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "depending on the site conditions. F.4.2 Operational Costs Operational costs will be a function of the number of rain events in the specific location. The rainfall frequency can be determined by the report, “Monthly Station Climate Summaries, 1971-2000” provided by the Depar", "page_or_section": "p. 273" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQV) and Water Quality Flows (WQF)", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Infiltration Basin, Infiltration Trench, Sand Filter", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltrate WQV, or portion thereof within a maximum of 96 hours.", "page_or_section": "Table B-2 / Appendix B, page 125" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "with a maximum 96-hour drawdown time", "page_or_section": "Design Elements – Infiltration Basin, page 128" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "with a maximum 96-hour drawdown time? Longer drawdown times may be allowable", "page_or_section": "Design Elements – Bioretention, page 179" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Separation from seasonally high water table > 5 ft., or less as justified by adequate groundwater information or RWQCB concurrence.", "page_or_section": "Table B-2, page 125" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Separation from seasonally high water table > 5 ft, or less as justified", "page_or_section": "Table B-4 Detention Device, page 136" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Is the media layer at least 18 in deep with a subsurface drainage layer at least 12 inches deep?", "page_or_section": "Design Elements – Bioretention, page 179" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Flow-path-to-width ratio of at least 2:1 recommended.", "page_or_section": "Table B-4, page 136" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "a length to width ratio of 2:1 should be provided for the sedimentation chamber", "page_or_section": "Table B-8 Media Filters, page 166" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. Caltrans Stormwater Quality Handbooks — Project Planning and Design Guide (June 2023)", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dot.ca.gov/-/media/dot-media/programs/design/documents/ppdg_final-ada-a11y.pdf", "landing_page_url": "https://dot.ca.gov/programs/design/manual-project-planning-design-guide", "retrieved_at": "2026-08-11T17:21:06.014Z", "original_filename": "ca-caltrans-project-planning.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:43:44.459Z", "enrich_model": "composer-2.5:run-c8ec7b06-0037-4a7c-bb9a-363a781f823a", "enrich_notes": "WQV/WQF sizing referenced throughout; no explicit WQV rainfall depth in inches in excerpts. Infiltration siting cites soil infiltration ≥0.5 in/hr and max 2.5 in/hr (not mapped to single design_infiltration_rate). Detention outlets: max 96 hr empty with 40–48 hr recommended; Austin Sand Filter 24 hr; Delaware Filter 40–48 hr. Bioretention subsurface drainage layer min 12 in (separate from media). Infiltration trench max depth ≤13 ft. Biofiltration strip max length ≤100 ft.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "carson-city-nv", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/carson-city-nv/", "data_url": "https://stormwateratlas.com/data/manuals/carson-city-nv.json", "document_metadata": { "jurisdiction_name": "Carson City", "jurisdiction_level": "municipality", "state_code": "NV", "document_title": "Carson City Drainage Manual (Low Impact Development)", "version_or_edition": "Revised 7/1/2021", "adoption_or_effective_date": "2021-07-01", "last_revised_date": "2021-07-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "LID required for new development/redevelopment. Flow-based post-construction controls sized for the 2-year runoff event from the connected drainage area. Volume-based controls capture/treat 90% of annual runoff volume. WQV = [(P)(RV)(A)]/12 with P = 1.5 in west of Carson Street and 0.5 in east of Carson Street. Detention attenuates post-development 10-year (Q10) peaks to predevelopment; volume credit for WQ features 1:1. Minor/major conveyance: 10-year / 100-year 24-hour; arterials/collectors checked for 100-year.", "peak_flow_calculation_method": [ "10-year / 100-year 24-hour design storms", "Detention to predevelopment Q10", "Rational / hydrograph methods per Drainage Manual technical criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "LID BMPs (infiltration, bioretention, etc.)", "Flow-based water quality controls", "Volume-based water quality controls", "Detention basins", "Infiltration trenches / basins", "Storm drain / channel conveyance" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Carson City Drainage Manual Revised: 7/1/2021", "page_or_section": "Headers" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = [(P)(RV)(A)]/12 ... P, use 1.5 inches for areas west of Carson Street and 0.5 inches for areas east", "page_or_section": "Technical Criteria / WQV" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minor storm event (10-year) and a major storm event (100-year)", "page_or_section": "Design Storm Events" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For P, use 1.5 inches for areas west of Carson Street and 0.5 inches for areas east of Carson Street", "page_or_section": "2.1.1.3 Volume-Based Water Quality Control Design, page 15" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the trench takes more than 72 hours to drain, then the rock fill should be removed", "page_or_section": "TC-1 Infiltration Trench limitations, page 93" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "recommended infiltration rate of 72 hours or less", "page_or_section": "TC-2 Infiltration Basin maintenance, page 95" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high-water table should be at least four feet (4') below the surface", "page_or_section": "Permeable paving design considerations, page 75" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration basins require a minimum soil infiltration rate of 0.5 inches/hour", "page_or_section": "TC-2 limitations, pages 90-93" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Outlet designed to discharge the capture volume over a period of 48 hours", "page_or_section": "Extended detention design and sizing guidelines, page 117" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio of at least 1.5:1 where feasible", "page_or_section": "Extended detention design and sizing guidelines, page 117" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_parameters.wqv_depth_inches" ] }, "source": { "document_url": "https://www.carson.org/home/showpublisheddocument/76280/637624691903200000", "landing_page_url": "https://www.carsoncity.gov/government/departments-g-z/public-works/storm-water-flood-plain-management/low-impact-development-drainage-manual-faqs", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "carson-city-nv.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:46:22.396Z", "enrich_model": "composer-2.5:run-c45f6b60-2be4-4085-aacb-d4c7482711c6", "enrich_notes": "WQV precipitation P is zone-specific: 1.5 in west of Carson Street and 0.5 in east (90th percentile depth in WQV formula). Infiltration basins also cite groundwater separation ≥3 m (~118 in) from invert to groundwater; permeable paving cites SHWT ≥4 ft below surface. Infiltration basin sizing uses 48 hr drawdown in invert area equation; upper infiltration rate threshold 2.4 in/hr before full pretreatment required.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "charlotte-nc", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/charlotte-nc/", "data_url": "https://stormwateratlas.com/data/manuals/charlotte-nc.json", "document_metadata": { "jurisdiction_name": "Charlotte-Mecklenburg", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "Charlotte-Mecklenburg Stormwater Design Manual", "version_or_edition": "April 2026 (public comment draft)", "adoption_or_effective_date": null, "last_revised_date": "2026-04", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method (with frequency factor Cf, custom runoff coefficients, and custom rainfall intensities)", "NRCS Method / Curve Number (TR-55; Type II center-weighted 6-hour storm unless otherwise specified)", "Custom Charlotte-Mecklenburg precipitation tables (Appendix 2)" ], "required_hydrologic_hydraulic_software": [ "HEC software (City verification)", "HydroCAD", "StormCAD" ], "approved_bmp_categories": [ "Vegetated channels (turfgrass and native plant)", "Armored channels (when vegetated not feasible)", "Closed pipe systems", "Culverts", "Riprap aprons (energy dissipation)", "Plunge pools (energy dissipation)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Charlotte-Mecklenburg Stormwater Design Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This manual has been developed to assist in the design and evaluation of stormwater management facilities in the City of Charlotte, Charlotte ETJ, and Mecklenburg County.", "page_or_section": "Chapter 1, Section 1.1, Page 6" }, { "field": "document_metadata.state_code", "excerpt": "Figure 1-2. Stormwater conveyance structures in Charlotte, NC", "page_or_section": "Chapter 1, Page 9" }, { "field": "document_metadata.document_title", "excerpt": "Charlotte-Mecklenburg Stormwater Design Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "A Certification of Adoption will be added when the final Design Manual is published.", "page_or_section": "Certification of Adoption, Page 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "The goals of the 2026 update to this manual are to", "page_or_section": "Chapter 1, Section 1.2, Page 7" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Streamline information by focusing on City of Charlotte, Charlotte ETJ, and Mecklenburg County requirements", "page_or_section": "Chapter 1, Section 1.2, Page 7" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 2-1. Summary of design storm requirements... Channels ... 10-yr ... At sags on local streets 25-yr ... At sags on arterials and primary access streets 50-yr ... Primary access streets 100-yr ... Streets across regulated floodways 100-yr, 24-hr per FEMA", "page_or_section": "Chapter 2, Table 2-1, Page 10" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 2-3. Frequency factors Recurrence Interval (years) Cf 2 1 10 1 25 1.1 50 1.2 100 1.25", "page_or_section": "Chapter 2, Table 2-3, Page 12" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Either the Rational Method or the NRCS Method may be applied, with watershed sizes, appropriate applications, and necessary adjustments detailed in the table below.", "page_or_section": "Chapter 2, Section 2.4, Page 11" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The NRCS method should be based on a Type II, center-weighted storm with a duration of six hours.", "page_or_section": "Chapter 2, Section 2.6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Note: For the NRCS method, use 6-hr durations unless otherwise specified.", "page_or_section": "Chapter 2, Table 2-1 note, Page 10" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The City will typically use HEC software to verify designs submitted by the development community. In addition, the City may check designs using HydroCAD and StormCAD. Designers may use any software tools that are based on the methods described in this manual.", "page_or_section": "Chapter 1, Section 1.3, Page 7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Use vegetated channels whenever feasible • Implement armored channels only when a vegetated channel is not feasible", "page_or_section": "Chapter 3, Table 3-1, Page 20" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "When designing vegetated channels, the designer may select either turfgrass or native plants.", "page_or_section": "Chapter 3, Section 3.4, Page 21" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "riprap aprons should be used for closed pipe system outlets and for culverts that convey drainage ditches and streams with intermittent flows, and plunge pools should be used for culverts that convey streams with perennial flows.", "page_or_section": "Summary of Technical Changes / Chapter 6" }, { "field": "practice_mentions.swale", "excerpt": "NCDEQ Stormwater Design Manual: C-11. Treatment Swale.", "page_or_section": "Chapter 3 | Channels | 3.11 References (page 40)" }, { "field": "practice_mentions.swale", "excerpt": "Ekka, S & Hunt, W. (2020). Swale Terminology for Urban Stormwater Treatment.", "page_or_section": "Chapter 3 | Channels | 3.11 References (page 40)" }, { "field": "enrich_notes", "excerpt": "Detention: Unless otherwise approved by Storm Water Services, stormwater detention effect from stormwater control measures, ponds, or reservoirs must not be taken into account when calculating flows from an existing drainage area to a stormwater conveyance design.", "page_or_section": "Chapter 2 | Hydrology | 2.3 Hydrologic Considerations (page 11)" }, { "field": "enrich_notes", "excerpt": "Design of SCMs", "page_or_section": "Chapter 2 | Hydrology | Table 2-2 Allowable uses for NRCS Method (page 11)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "April 2026 public-comment draft (Certification of Adoption not yet published). Manual covers conveyance design (hydrology, channels, pipes, culverts, energy dissipators); post-construction water quality volume / SCM sizing is deferred to separate Post Construction Stormwater Ordinances/Regulations referenced in §1.7—not specified in this text. Software listed is City verification tooling; designers may use any method-based tools. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.charlottenc.gov/files/sharedassets/city/v/1/services/stormwater/documents/regulations/storm-water-design-manual/public-comment/charlotte-sw-design-manual-for-public-comment.pdf", "landing_page_url": "https://www.charlottenc.gov/Services/Stormwater/Stormwater-Regulations/Storm-Water-Design-Manual", "retrieved_at": "2026-08-08T10:41:44.548Z", "original_filename": "charlotte-nc.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T07:49:35.306Z", "enrich_model": "composer-2.5:run-f9d45efb-fc73-448e-8c3c-92fe840f2586", "enrich_notes": "Corpus is the Charlotte-Mecklenburg Stormwater Design Manual conveyance draft (hydrology, vegetated/armored channels, closed pipes, culverts, energy dissipators). Atlas notes post-construction water quality volume and SCM sizing are deferred to separate Post Construction Stormwater Ordinances referenced in §1.7—not present in these excerpts. Table 2-2 allows NRCS for design of SCMs, but no SCM numeric sizing criteria appear. Channel Table 3-1 gives 2 ft preferred bottom width and 2–7% longitudinal slope for channels, not labeled as treatment swales.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "juneau-ak", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/juneau-ak/", "data_url": "https://stormwateratlas.com/data/manuals/juneau-ak.json", "document_metadata": { "jurisdiction_name": "City and Borough of Juneau", "jurisdiction_level": "municipality", "state_code": "AK", "document_title": "Alaska Storm Water Guide (capital MS4)", "version_or_edition": "December 2011", "adoption_or_effective_date": "2011-12", "last_revised_date": "2011-12", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 100 ], "water_quality_volume_method": "Treat runoff from 90% of average-year storms (goal: 80% average annual post-development TSS reduction). WQv = (Rv)×(A)×(P)/12 where P is the 90% cumulative frequency rainfall depth (~0.5–1.25 in by climatic region).", "peak_flow_calculation_method": [ "Rational Method", "TR-55", "WinTR-20 / SCS methods", "HEC-HMS", "EPA SWMM" ], "required_hydrologic_hydraulic_software": [ "ILLUDAS", "TR55-1986", "WinTR55", "WinTR20 SCS", "HEC-HMS" ], "approved_bmp_categories": [ "Wet Pond", "Extended Storage Pond / Dry ED Ponds", "Dry Pond", "Wet Vaults", "Oil/Grit Separator", "Dry Swale / Wet Swale", "Bioretention / Infiltration" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Juneau capital MS4 follows Alaska Storm Water Guide", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat runoff from 90% of average-year storms", "page_or_section": "Alaska Storm Water Guide" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the rainfall depth associated with 90 percent of the runoff producing storms is 1.25 inches", "page_or_section": "Chapter 2, Box 1 Example 1 (Coastal Climatic Region), page 59" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = design rainfall depth (90% cumulative frequency depth) (~ 0.5 to 1.25 inches)", "page_or_section": "Table 3-4 Unified sizing criteria, page 78" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1-year, 24-hour duration storm event", "page_or_section": "Table 3-4 Channel Protection Storage Volume Cpv, page 78" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green roofs can be installed on building roofs with slopes up to 25 percent.", "page_or_section": "Chapter 5 Green Roof Design Adaptation for Alaska, page 200" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Alaska Storm Water Guide.", "fields_not_found": [] }, "source": { "document_url": "https://plants.alaska.gov/pdf/akswguide.pdf", "landing_page_url": "https://plants.alaska.gov/", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "juneau-ak.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 25, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:44:30.196Z", "enrich_model": "composer-2.5:run-2bba3978-fca6-4462-a82a-294c45b41242", "enrich_notes": "WQv uses P from local 90% storm or snowmelt analysis; Coastal/Southeast example uses 1.25 in rainfall (Interior examples use 0.5 in rain or 1.2 in melt). Unified sizing also cites P roughly 0.5–1.25 in and annual rainfall note up to 1.25–1.75 in. Juneau aligns with Coastal region feasibility tables. Oil/grit separators need 50% TSS removal for particles >20 µm under 2-year, 6-hour event (ADEC non-objection), not a numeric MTD verification program.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "honolulu-hi", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/honolulu-hi/", "data_url": "https://stormwateratlas.com/data/manuals/honolulu-hi.json", "document_metadata": { "jurisdiction_name": "City and County of Honolulu", "jurisdiction_level": "municipality", "state_code": "HI", "document_title": "Rules Relating to Storm Drainage Standards", "version_or_edition": "August 2017", "adoption_or_effective_date": "2017-08", "last_revised_date": "2017-08", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method (Q = CIA) for drainage areas of 100 acres or less", "Plate 6 Design Curves for Peak Discharge vs. Drainage Area (USGS flood-frequency / 100-year) for drainage areas greater than 100 acres" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Closed conduits (storm drains)", "Open channels", "Roadway culverts and bridges", "Low impact development best management practices (per separate Rules Relating to Water Quality)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Department of Planning and Permitting City and County of Honolulu Honolulu, Hawaii", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "design of storm drainage facilities in the City and County of Honolulu", "page_or_section": "Introduction" }, { "field": "document_metadata.state_code", "excerpt": "Honolulu, Hawaii", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORM DRAINAGE STANDARDS", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "This edition supersedes the Rules Relating to Storm Drainage Standards, January 2000 (Repealed August 16, 2017).", "page_or_section": "Introduction" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "These standards have been prepared pursuant to Article 12, Chapter 14, Revised Ordinances of Honolulu, 1990 as amended", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For drainage areas of 100 acres or less, Tm (recurrence interval) = 10 years, unless otherwise specified.", "page_or_section": "Part I.A.1, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For drainage areas of 100 acres or less with sump, or tailwater effect and for the design of roadway culverts and bridges, Tm (recurrence interval) = 50 years.", "page_or_section": "Part I.A.2, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For drainage areas greater than 100 acres and all streams... Tm (recurrence interval) = 100 years.", "page_or_section": "Part I.A.3, Page 1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For drainage areas of 100 acres or less, the rational method shall be used.", "page_or_section": "Part I.B.1, Page 1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The formula Q = CIA shall be used to determine quantities of flow rate", "page_or_section": "Part I.C Rational Method, Page 2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Plate 6 titled, \"Design Curves for Peak Discharge vs. Drainage Area\" should be used to determine the 100-year peak discharge.", "page_or_section": "Part I.B.2.a, Page 1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "C. CLOSED CONDUITS... D. OPEN CHANNELS", "page_or_section": "Table of Contents / Part II" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "New development and redevelopment projects shall also comply with the requirements in the Rules Relating to Water Quality to implement low impact development best management practices to reduce discharge of pollutants into the final receiving waters.", "page_or_section": "Part II.A.13, Page 5" }, { "field": "practice_mentions.swale", "excerpt": "Where sump conditions exist, a safety measure such as an overflow swale shall be provided to prevent flooding of adjacent lots", "page_or_section": "PART II A. GENERAL CONDITIONS §5, page 9" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "New development and redevelopment projects shall also comply with the requirements in the Rules Relating to Water Quality to implement low impact development best management practices", "page_or_section": "PART II B. DESIGN COMPUTATIONS, page 10" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Detention volume and discharge rate.", "page_or_section": "PART II B. DESIGN COMPUTATIONS (interim measures data), page 11" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Conveyance/hydrologic standards only. Water quality volume and LID BMP sizing are deferred to separate Rules Relating to Water Quality (not in this PDF). Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.honolulu.gov/dpp/wp-content/uploads/sites/56/2024/07/rules-storm-drainage-standards.pdf", "landing_page_url": "https://www.honolulu.gov/dpp/", "retrieved_at": "2026-08-08T11:41:37.854Z", "original_filename": "honolulu-hi.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T08:35:08.098Z", "enrich_model": "composer-2.5:run-dd7ff023-270e-4cb1-978a-0eaa9fc1ccca", "enrich_notes": "Document is Rules Relating to Storm Drainage Standards (conveyance/hydrology: recurrence 10/50/100 yr, rational method, Manning pipes/channels). Water-quality volume and LID BMP sizing are explicitly deferred to separate Rules Relating to Water Quality. Interim drainage may require detention volume and discharge rate but no SCM drawdown or WQv depth is stated here.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "akron-oh", "processed_at": "2026-08-17T03:19:55.590Z", "detail_url": "https://stormwateratlas.com/akron-oh/", "data_url": "https://stormwateratlas.com/data/manuals/akron-oh.json", "document_metadata": { "jurisdiction_name": "City of Akron", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Rainwater and Land Development — Ohio's Standards for Stormwater Management (city MS4)", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "WQv (ac-ft) = C × 0.75 × A / 12 (treat runoff from 0.75 inch of precipitation); Ohio EPA NPDES requires 20% additional WQv for sediment; extended detention drawdown 24–48 hours. Used where no durable city design-manual PDF was found (or prior extract was empty/scanned).", "peak_flow_calculation_method": [ "NRCS TR-55", "USGS empirical equations for small urban streams in Ohio", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water Quality Ponds", "Infiltration / Filtration practices", "LID / Conservation Development", "Wetland / Stream setbacks" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Akron MS4 — Ohio Rainwater and Land Development standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "for construction activities. WQv (ac-ft) = C * 0.7\u0018 * A / \u00182 (Equation \u0018) Where: C = runoff coefficient A = area draining into the BMP in acres The runoff coefficient, C, is calculated using the following equation or alternatively values provided in the current Ohio EPA NP", "page_or_section": "p. 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 0.75 inch precipitation depth", "page_or_section": "CHAPTER 2 Bioretention Design Checklist, page 83" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv (ac-ft) = C * 0.75 * A / 12 (Equation 1)", "page_or_section": "CHAPTER 2 Water Quality Volume, pages 37/376" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a minimum 4ft of separation required between the water table and the bioretention practice", "page_or_section": "CHAPTER 2 Bioretention, page 77" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "ds = planting soil depth (2.5 feet minimum)", "page_or_section": "CHAPTER 2 Bioretention, page 84" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "may be designed up to 12 inches provided ponding will not damage plant materials", "page_or_section": "CHAPTER 2 Bioretention, page 80" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 48-hour period", "page_or_section": "Dry Extended Detention Basin – Design Criteria, page 40/377" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "length generally exceeding 2:1 (length:width)", "page_or_section": "CHAPTER 2 Bioretention, pages 80/84" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "drained over a 24-48 hour period", "page_or_section": "Water Quality Volume (all pond configurations), page 37" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide Ohio manual used as MS4 post-construction reference when city PDF unavailable/empty.", "fields_not_found": [] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "akron-oh.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": null, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:20:05.565Z", "enrich_model": "composer-2.5:run-ad0e03bc-5dc9-42d5-9399-1dfde814ccf9", "enrich_notes": "Ohio WQv uses P=0.75 in (WQv ac-ft = C × 0.75 × A / 12); Ohio EPA requires +20% WQv for sediment. Extended-detention drawdown varies by pond type (dry ED 48 h; wet ED 24 h; general WQv pond language 24–48 h). Infiltration trench: soil Ks 0.5–2.0 in/hr, WQv drain 24–48 h, ≥24 in clearance from SHWT to trench bottom. Bioretention: ≥40 h drawdown (Ohio EPA), 2.5 ft min planting soil, ponding generally <6 in up to 12 in, 4 ft min SHWT separation required (2 ft recommended). Wet permanent pool mean depth 3–6 ft; wetland pool depths often 6–18 in (avg 6–12 in). Sand filter design drawdown 40 h total.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "albany-ny", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/albany-ny/", "data_url": "https://stormwateratlas.com/data/manuals/albany-ny.json", "document_metadata": { "jurisdiction_name": "City of Albany", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "New York State Stormwater Management Design Manual (adopted; capital MS4)", "version_or_edition": "July 31, 2024", "adoption_or_effective_date": "2024-07-31", "last_revised_date": "2024-07-31", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "USDA NRCS TR20", "HydroCAD", "Pond Pack", "StormCAD", "Hydraflow", "HEC-HMS" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Practices", "Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Albany capital MS4 follows NYS Design Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) 90% Rule: WQv (acre-feet) = (P ∙ Rv ∙ A) / 12 Rv = 0.05+0.009(I) I = Impervious Cover (Percent) P(inches) = 90% Rainfall Event Number (See Figure 4.1) 2 A = Contributing Area (acres) Runoff Reduction Volume (RRv) RRv (acre-feet) = Reduction of", "page_or_section": "p. 43" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "90th percentile rainfall 1.20 inches (Section 4.2)", "page_or_section": "Chapter 7, Table 7.1" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min 2 ft separation to seasonal high-water table or bedrock", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of filter media shall be 30 inches min and 48 inches max", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max ponding is 12 inches (WQv) and 18 inches (Extreme Flood)", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underlying soils shall have an min. infiltration rate of 0.50 inch/hr", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size outlet structure to detain WQv for 24 hrs (12 hrs to trout waters)", "page_or_section": "Fact Sheet: Wet Pond (P-2), Chapter 6" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Min. flow path of 1.5:1 (length to relative width) from all inlet points to the outflow points across the pond", "page_or_section": "Fact Sheet: Wet Pond (P-2), Chapter 6" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be a min of 2 ft and a max of 8 ft", "page_or_section": "Fact Sheet: Dry Swale (O-1), Chapter 6" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Channel slope shall be 0.50% min and 4.0% max", "page_or_section": "Fact Sheet: Dry Swale (O-1), Chapter 6" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Infiltration rain gardens shall have a 12 inch minimum and 18 inch maximum filter media depth", "page_or_section": "Fact Sheet: Rain Garden (RR-6), Chapter 5" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide 100' horizontal separation distance from wells and 4' vertical distance from the water table.", "page_or_section": "Table 3.5 Watershed/Regional Selection Matrix, Chapter 3" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "soils with an infiltration rate less than 0.5 in/hr", "page_or_section": "Chapter 3, Step 3 (RRv site limitations)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NYS Stormwater Management Design Manual (Syracuse/Yonkers pattern).", "fields_not_found": [] }, "source": { "document_url": "https://extapps.dec.ny.gov/fs/projects/24-25DraftCGPDesignManual/Manual.SW.CGP.2024-07-31.Design_Manual_Issued_2024-07-31.pdf", "landing_page_url": "https://dec.ny.gov/environmental-protection/water/water-quality/stormwater/construction-stormwater-toolbox", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "albany-ny.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:21:44.004Z", "enrich_model": "composer-2.5:run-060ca5c6-584b-40ac-bed0-2c251d8c532f", "enrich_notes": "Albany follows NYS Stormwater Management Design Manual: WQv uses 90th-percentile P (example 1.20 in); RRv requires 100% WQv reduction before end-of-pipe SMPs unless documented infeasibility (e.g. SHWT, bedrock, fc < 0.5 in/hr). SHWT separation is often 2 ft (24 in), increased to 4 ft in sole-source aquifers for some practices. Wet-pond WQv detention is 24 hr (12 hr in trout waters). Rain gardens (RR-6) use lower filter-media mins (12–18 in) than Chapter 6 bioretention (30 in min).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "alexandria-va", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/alexandria-va/", "data_url": "https://stormwateratlas.com/data/manuals/alexandria-va.json", "document_metadata": { "jurisdiction_name": "City of Alexandria", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Green Streets and Sidewalks Stormwater Design Guidelines", "version_or_edition": "2020 Final", "adoption_or_effective_date": null, "last_revised_date": "2020-01-01", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "ROW BMP water quality sizing per Virginia BMP Clearinghouse standards: runoff from the 90th percentile 1-inch rainfall (VSMP) and/or the City Water Quality Volume Default of the first ½ inch of runoff from total impervious area. Urban bioretention and permeable pavement are primary ROW BMPs.", "peak_flow_calculation_method": [ "Virginia BMP Clearinghouse sizing", "Virginia Stormwater Management Program criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Urban bioretention / tree wells", "Mid-sidewalk bioretention", "Back of sidewalk bioretention", "Bus bulb bioretention", "Permeable pavement (sidewalks, parking, bike lanes)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Alexandria, Virginia", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Alexandria", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "GREEN STREETS AND SIDEWALKS STORMWATER DESIGN GUIDELINES", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "rvice_content/attachments/ BGI_Workshop_Final.pdf --- page 83 ---", "page_or_section": "pp. 81–83" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "supplement the Virginia BMP Clearinghouse standards and specifications", "page_or_section": "Preface" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "90th percentile rainfall depth of 1 inch ... first ½ inch of runoff from the total impervious area ... Water Quality Volume Default", "page_or_section": "Water Quality Sizing" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Virginia BMP Clearinghouse standards and specifications", "page_or_section": "Water Quality Sizing" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Urban Bioretention; Permeable Pavement", "page_or_section": "TOC" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the bottom of the the soil underneath the proposed bioretention must be at least 2 feet above bedrock or the seasonal high groundwater table", "page_or_section": "3.1 PLANNING FOR STORMWATER, page 31" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil infiltration tests must demonstrate that at least ½ inch of water can percolate into the soil per hour", "page_or_section": "3.1 PLANNING FOR STORMWATER, page 31" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Runoff from a storm with the 90th percentile rainfall depth of 1 inch", "page_or_section": "3.1 PLANNING FOR STORMWATER, page 31" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first ½ inch of runoff from the total impervious area of the site as per the City's Water Quality Volume Default", "page_or_section": "3.1 PLANNING FOR STORMWATER, page 31" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "PONDING DEPTH DOES NOT EXCEED 1 FOOT", "page_or_section": "DETAIL 10 Green Alley, DESIGN NOTES 1, page 62" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "RESERVOIR LAYER 9\" MIN. SEE DESIGN NOTE 2", "page_or_section": "DETAIL 10 Green Alley, page 62" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "meet the design dewatering time for the facility", "page_or_section": "Maintenance / sand wicks, page 46" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "ROW-focused green streets guidelines; site development still relies on full VA BMP Clearinghouse / VESMP. Not a complete city stormwater design manual. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://media.alexandriava.gov/docs-archives/tes/stormwater/alexandria-gs-sw-design-guidelines=2020=final=1=.pdf", "landing_page_url": "https://www.alexandriava.gov/stormwater-management/green-street-and-sidewalk-stormwater-design-guidelines", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "alexandria-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:22:57.546Z", "enrich_model": "composer-2.5:run-72639132-0ba6-4a86-bae2-7e6f16f0f7fa", "enrich_notes": "Document supplements Virginia BMP Clearinghouse for ROW urban bioretention and permeable pavement; dual WQ sizing cited (VSMP 90th-percentile 1-inch rainfall vs. City first 0.5 inch runoff from TIA). Alexandria defaults to HSG D and underdrains; permeable pavement prohibited where longitudinal slope exceeds 5%; lined systems min 2% bottom slope. Frost penetration 24 inches per building code referenced for permeable pavement freeze-thaw.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "allentown-pa", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/allentown-pa/", "data_url": "https://stormwateratlas.com/data/manuals/allentown-pa.json", "document_metadata": { "jurisdiction_name": "City of Allentown", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual (city Ch.538 cites PA Stormwater BMP Manual / Act 167)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "PA PCSM Manual pollutant-load approach coupling volume and water quality management: land-cover pollutant concentrations applied to runoff, volume reductions through SCMs credited, and post-construction loads compared to pre-construction. Allentown Chapter 538 Stormwater Management / Act 167 ordinance requires BMPs consistent with the Pennsylvania Stormwater BMP Manual.", "peak_flow_calculation_method": [ "PA PCSM / Stormwater BMP Manual methods", "Act 167 stormwater management ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Volume-reducing SCMs", "Water quality SCMs", "Post-construction BMPs per PA Manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Allentown Act 167 Stormwater Management Ordinance (Chapter 538) cites Pennsylvania Stormwater Best Management Practices Manual", "page_or_section": "Coverage note / ecode360" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DRAFT / Page 1-3 1.1 OVERVIEW OF PCSM MANUAL This PCSM Manual establishes DEP-approved procedures for conducting PCSM stormwater analyses and provides SCM standards that can be used for regulatory compliance under Chapter 102. These procedures and standards may be applied to he", "page_or_section": "p. 12" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "pollutant load approach, coupling volume and water quality management", "page_or_section": "PA PCSM Manual" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / Page B-31" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Non-infiltration SCMs should generally be used ... where a two-foot separation distance from the bottom of the SCM to a limiting zone (e.g., SHWT, bedrock) is not met", "page_or_section": "Section 3.5.4 Infiltration Trench / Page 3-135" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil media depth should be at least 18 inches.", "page_or_section": "Section 3.4.6 Vegetated Conveyance / Page 3-96" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Table 3-90 ... 3.6.1 Bioretention ... Soil Media Depth Min. 18 in", "page_or_section": "Section 3.9.2 Table 3-90 / Page 3-310" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Table 3-90 ... 3.6.1 Bioretention ... Maximum Ponding/Storage Depth ... 2 ft", "page_or_section": "Section 3.9.2 Table 3-90 / Page 3-310" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Section 3.8.1 Wet Basin / Page 3-286" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The length to width ratio of the basin should be a minimum of 2:1 to avoid short circuiting.", "page_or_section": "Section 3.8.1 Wet Basin / Page 3-286" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio should be at least two to one.", "page_or_section": "Section 3.6.6 Engineered Stormwater Treatment Wetland / Page 3-205" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Table 3-90 ... 3.6.2 Green Roof ... Min. 3 in (Typically, lightweight growing material.)", "page_or_section": "Section 3.9.2 Table 3-90 / Page 3-310" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Section 3.5.4 Infiltration Trench / Page 3-135 (SCM-specific; no single site-wide max reported)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No standalone Allentown design-manual PDF found; municipality coverage via PA PCSM Manual referenced by city ordinance. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "design_parameters.shwt_separation_inches" ] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-10T09:54:53.533Z", "original_filename": "allentown-pa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:23:47.438Z", "enrich_model": "composer-2.5:run-ffdcf1e0-7ff7-424a-afba-150c82fddbc3", "enrich_notes": "PA PCSM Manual (Act 167 / Ch.538 reference): pollutant-load WQM; infiltration SCMs generally require 2 ft SHWT separation; bioretention/bioinfiltration min 18 in filter media; wet basin min 5 ft permanent pool sized to 1.2 in/2 hr runoff; infiltration marginal soil thresholds 0.25–0.4 in/hr cited for SCM selection not a universal design rate.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "amarillo-tx", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/amarillo-tx/", "data_url": "https://stormwateratlas.com/data/manuals/amarillo-tx.json", "document_metadata": { "jurisdiction_name": "City of Amarillo", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Water Management Criteria Manual", "version_or_edition": "Posted on City of Amarillo Web Page 03/13/08", "adoption_or_effective_date": null, "last_revised_date": "2008-03-13", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Minor and major drainage systems with design storm frequency criteria; Rational Method hydrology; street capacity for minor/major storms; detention and retention provisions (1.3.15). Peak flow curves provided for 2- through 100-year events.", "peak_flow_calculation_method": [ "Rational Method", "Minor / major storm street and gutter capacity", "Storm sewer design storm frequency tables", "Detention and retention sizing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention facilities", "Retention facilities", "Storm sewers / street conveyance", "Open channels / culverts" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF AMARILLO", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CITY OF AMARILLO", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "2-6 Depth-Duration-Frequency Data for Amarillo. Texas . . . . . . . . . . . . . . . . . . . 2-19 SECTION 3 STREET DRAINAGE . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1 Minor Storm Runoff Allowable Street Use 3-6 3-2 Manning's Roughness Coefficients for Streets and G", "page_or_section": "p. 13" }, { "field": "document_metadata.document_title", "excerpt": "Storm Water Management Criteria Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Management Criteria Manual CITY OF AMARILLO", "page_or_section": "p. 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Storm Water Management Criteria Manual", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-Year / 5-Year / 10-Year / 25-Year Peak Flow Curves", "page_or_section": "Chapter 2 figures" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Minor Storm Provisions / Major Storm Provisions / Detention and Retention", "page_or_section": "1.3 / 1.3.15" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "2.2 RATIONAL METHOD", "page_or_section": "Chapter 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention and Retention", "page_or_section": "1.3.15" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum ponding time recommended is 72 hours.", "page_or_section": "9.7.1 Infiltration Basin, Section 9, page 9-30" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The soils must have an infiltration rate of 0.27 inches/hour or greater to be considered for an infiltration basin.", "page_or_section": "9.7.1 Infiltration Basin, Section 9, page 9-30" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonally high water table should be 1 to 2 feet below the bottom of the swale.", "page_or_section": "9.7.3 Vegetated Swales, Section 9, page 9-33" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The grade of the channel should be as flat as possible, and should not exceed 2 percent.", "page_or_section": "9.7.3 Vegetated Swales, Section 9, page 9-33" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "2008-posted criteria manual still hosted 2024; confirm current adoption status. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.amarillo.gov/wp-content/uploads/2024/09/Storm-Water-Management-Cri.pdf", "landing_page_url": "https://www.amarillo.gov/capital-projects-and-development/", "retrieved_at": "2026-08-10T08:48:28.515Z", "original_filename": "amarillo-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.27, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale" ], "enriched_at": "2026-08-13T07:24:19.269Z", "enrich_model": "composer-2.5:run-2f43ba3b-20d2-46b9-b972-437e7b3bfbd8", "enrich_notes": "Manual emphasizes detention/retention, playas, and Section 9 BMPs. Infiltration basins require soil infiltration ≥0.27 in/hr and max ponding 72 hr (dm=f×TP). Parking-lot detention: max 7 in ponding, drain ≤30 min; property-line swales allow up to 6 in temporary ponding. No explicit WQv rainfall depth; hydrology uses Rational Method with 2–100-year intensities. Combination detention/infiltration spillway crest tied to three-day (72 hr) infiltration capacity.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "anaheim-ca", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/anaheim-ca/", "data_url": "https://stormwateratlas.com/data/manuals/anaheim-ca.json", "document_metadata": { "jurisdiction_name": "City of Anaheim", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Drainage Manual for Public and Private Drainage Facilities — Division IV Private Storm Drainage Facilities Requirements", "version_or_edition": "August 2005", "adoption_or_effective_date": null, "last_revised_date": "2005-08", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 100 ], "water_quality_volume_method": "City adopts Orange County Hydrology Manual and Local Drainage Manual with Anaheim revisions (other divisions). This Division IV covers private facility design criteria; sump inlets designed for Q25 with 100-year habitable-area protection if grate fully clogs.", "peak_flow_calculation_method": [ "Private drains tributary to Santa Ana River (not connected to public facilities): minimum 10-year recurrence interval", "Onsite sump grate inlets designed to capture Q25", "100-year protection of habitable areas with emergency overflow / freeboard if grate clogs 100%" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Private storm drains", "Grate inlets / sump systems", "Emergency overflow conveyance" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF ANAHEIM", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Anaheim", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Santa Ana River", "page_or_section": "Section 1" }, { "field": "document_metadata.document_title", "excerpt": "DRAINAGE MANUAL FOR PUBLIC AND PRIVATE DRAINAGE FACILITIES DIVISION IV", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "PRIVATE STORM DRAINAGE FACILITIES REQUIREMENTS", "page_or_section": "Division IV" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minimum of the 10-year storm / capture Q25 / 100-year protection of habitable areas", "page_or_section": "Section 1 Design Criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "special drainage design requirements for private storm drains", "page_or_section": "Section 1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Onsite inlets in sump condition shall be designed to capture Q25", "page_or_section": "Section 1.D" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Grate inlets are allowed on private property", "page_or_section": "Section 1.D" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Onsite inlets in sump condition shall be designed to capture Q25.", "page_or_section": "Section 1 – Design Criteria D.1.b, page 3" }, { "field": "practice_mentions", "excerpt": "This section presents special drainage design requirements for private storm drains within the City of Anaheim.", "page_or_section": "Section 1 – Design Criteria, page 3" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Anaheim Division IV only (10 pages). Full city criteria also in Div I–III adopting OC manuals with revisions — already have orange-county-ca LDM. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.anaheim.net/DocumentCenter/View/1077", "landing_page_url": "https://www.anaheim.net/589/Storm-Drainage-Manual-Public-Private-Fac", "retrieved_at": "2026-08-10T08:05:33.346Z", "original_filename": "anaheim-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T07:24:41.300Z", "enrich_model": "composer-2.5:run-f761353c-88f9-4b85-a1af-01f2a871cec9", "enrich_notes": "Division IV (Aug 2005) covers private storm drainage only: recurrence (10-year minimum in defined Santa Ana tributary cases), pipe diameters, manhole spacing, sump grate inlets (Q25 design; 100-year habitable-area protection with 100% grate clog; ≥1.0 ft freeboard for emergency overflow), sump pumps (Q25), and plastic pipe limits. No water-quality volume depth, SCM/BMP sizing, infiltration, or canonical treatment practice criteria appear in these excerpts; atlas notes WQv/BMPs via Orange County Hydrology Manual and Local Drainage Manual with Anaheim revisions.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ann-arbor-mi", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/ann-arbor-mi/", "data_url": "https://stormwateratlas.com/data/manuals/ann-arbor-mi.json", "document_metadata": { "jurisdiction_name": "City of Ann Arbor", "jurisdiction_level": "municipality", "state_code": "MI", "document_title": "Washtenaw County WRC Rules and Guidelines — Procedures & Design Criteria for Stormwater Management Systems (adopted by Ann Arbor Ch.63)", "version_or_edition": "August 6, 2014 (amended / mirror PDF)", "adoption_or_effective_date": "2014-08-06", "last_revised_date": "2016-10-17", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 100 ], "water_quality_volume_method": "First flush = runoff from the first inch of rain (Rational Method); treat to ≥80% TSS removal or ≤80 mg/L TSS. Bankfull = 2-year/24-hour (NRCS). Infiltrate the greater of (post−pre bankfull volume) OR entire first flush. Flood control storage release ≤0.15 cfs/acre. Also size for 100-year (NRCS).", "peak_flow_calculation_method": [ "Rational Method (first flush)", "NRCS Method (bankfull / 100-year)", "Fixed release rate 0.15 cfs/acre for flood-control storage" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration BMPs", "Detention / retention systems", "Bioretention / rain gardens", "Swales", "Pretreatment / treatment train BMPs", "SEMCOG LID practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Ann Arbor follows Washtenaw County Water Resources Commissioner Rules (Ch.63 by reference)", "page_or_section": "Coverage note / city stormwater page" }, { "field": "document_metadata.document_title", "excerpt": "Washtenaw County Water Resources Commissioner Rules and Guidelines Procedures & Design Criteria For Stormwater Management Systems", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "First flush volume; the runoff from the first inch of rain ... 80 percent removal of TSS ... Bankfull volume; the 2-year recurrence interval /24 hour storm ... release rate ... will not exceed 0.15 cfs per acre", "page_or_section": "§IV Volume Treatment / flood control" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent county WRC rules adopted by city ordinance", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "first flush is the runoff from the first inch of precipitation", "page_or_section": "Section VIII Glossary, page 107" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "BMPs must be engineered to properly dewater within 48 hours of the storm event", "page_or_section": "Section IV, page 25" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "infiltration BMPs should be designed so that they completely empty within 48 hours", "page_or_section": "Section V Part D.5, page 64" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "maintain at least a 3-foot clearance above the seasonally high water table for most BMPs", "page_or_section": "Section V Part D.5, page 63" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum depth of ponding is 8 inches", "page_or_section": "Section V Rain Garden, page 70" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Used 2014 WCWRC Rules PDF (city adopts WCWRC). County may have Oct 2016 update; verify against current washtenaw.org asset if available.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://annarborchronicle.com/wp-content/uploads/2014/08/WCWRC-Rules-2014_071614.pdf", "landing_page_url": "https://www.washtenaw.org/221/Rules-Design-Standards", "retrieved_at": "2026-08-10T09:54:53.490Z", "original_filename": "ann-arbor-mi.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 8, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:25:51.479Z", "enrich_model": "composer-2.5:run-6cb0e08e-946a-4fb9-939d-11e70bca550d", "enrich_notes": "First flush WQ volume is the first inch of precipitation (Rational Method). Infiltration design uses safety factor of 2 on measured rates; site suitability down to 0.1 in/hr. Infiltration volume credits use a 6-hour infiltration period in worksheets. Rain gardens allow 2 ft SHWT clearance vs 3 ft for most BMPs. Extended wet/dry detention glossary cites 24–40 hr detention, not a single design hour.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "annapolis-md", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/annapolis-md/", "data_url": "https://stormwateratlas.com/data/manuals/annapolis-md.json", "document_metadata": { "jurisdiction_name": "City of Annapolis", "jurisdiction_level": "municipality", "state_code": "MD", "document_title": "Maryland Stormwater Design Manual (capital MS4 / ESD to the MEP)", "version_or_edition": "Volume One", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "WQv = (P)(Rv)(A)/12 with P = 1.0 in Eastern / 0.9 in Western Rainfall Zone; ESD to the MEP per Maryland Stormwater Design Manual (same framework as Baltimore).", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Systems", "Open Channel Practices", "Non-structural / ESD Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Annapolis capital MS4 follows Maryland Stormwater Design Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv is calculated as (P)(Rv)(A)/12, where P is the rainfall depth (1.0 inch ... 0.9 inch ...)", "page_or_section": "MD Design Manual Vol.1" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P= rainfall depth in inches and is equal to 1.0\" in the Eastern Rainfall Zone and 0.9\" in the Western Rainfall Zone", "page_or_section": "Chapter 2, Table 2.1 / Section 2.0, page 39" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "ED 24 hour drawdown of the water quality volume", "page_or_section": "Table 1.3 Symbols, page 36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The water quality requirement can be met by providing a 24 hour drawdown of a portion of the water quality volume (WQv)", "page_or_section": "Chapter 2, Section 2.4, page 42" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention for Water Quality Volume: ... a 24 hour drawdown of a portion of the water quality volume (WQv)", "page_or_section": "Chapter 2, Section 2.4, page 42" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "filter bed inverts shall be separated at least four feet vertically (two feet on the lower Eastern shore) from the seasonal high water table", "page_or_section": "Chapter 5, Micro-bioretention, page 245" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The invert of the stone reservoir shall be separated at least four feet (two feet on the lower Eastern Shore) from the seasonal high water table", "page_or_section": "Chapter 5, Enhanced Filters, page 261" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention systems (F-6) shall consist of the following treatment components: A 2½ to 4 foot deep planting soil bed", "page_or_section": "Chapter 3, Section 3.4.5, page 121" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Filter beds shall be between 24 and 48 inches deep", "page_or_section": "Chapter 5, Micro-bioretention, page 245" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 12\" deep surface ponding area", "page_or_section": "Chapter 3, Filtering Systems, page 121" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Temporary storage of the ESDv may be provided above the facility with a surface ponding depth of 12 inches or less", "page_or_section": "Chapter 5, Micro-bioretention, page 245" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Flowpaths of 1.5:1 (length relative to width) and irregular shapes are recommended", "page_or_section": "Chapter 3, Section 3.1.4 Pond Treatment Criteria, page 92" }, { "field": "practice_mentions.extended_detention", "excerpt": "Cpv = 24 hour (12 hour in USE III and IV watersheds) extended detention of post-developed one-year, 24 hour storm event", "page_or_section": "Chapter 2, Table 2.1, page 39" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "I-2 infiltration basin ... capture and temporarily store the WQv before allowing it to infiltrate into the soil over a two day period", "page_or_section": "Chapter 2, Section 2.7, page 76" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Maryland Stormwater Design Manual (Baltimore pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_parameters.wqv_depth_inches" ] }, "source": { "document_url": "https://mde.maryland.gov/programs/water/StormwaterManagementProgram/Documents/www.mde.state.md.us/assets/document/sedimentstormwater/MD%20SWM%20Volume%201.pdf", "landing_page_url": "https://mde.maryland.gov/programs/water/stormwatermanagementprogram/pages/stormwater_design.aspx", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "annapolis-md.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:26:15.241Z", "enrich_model": "composer-2.5:run-70df81c0-1532-4a50-adb4-5ea127df07cf", "enrich_notes": "WQv rainfall P is 1.0 in Eastern Rainfall Zone and 0.9 in Western Rainfall Zone (Annapolis follows Maryland statewide criteria; atlas cites Eastern 1.0 in). SHWT separation is 4 ft (48 in) minimum for micro-bioretention and enhanced-filter reservoir inverts, with 2 ft (24 in) on the lower Eastern Shore. Rain gardens require location at least 2 ft above seasonal high water table with 6 in max surface ponding; micro-bioretention allows up to 12 in ponding and filter beds 24–48 in deep. Infiltration practices (I-1, I-2) must infiltrate WQv over a two-day period (48 h), distinct from 24 h ED drawdown for WQv in ponds/wetlands. Cpv extended detention is 24 h (12 h in USE III and IV watersheds). Filter permeability k is given in ft/day (e.g., bioretention soil 0.5 ft/day), not as design infiltration in in/hr. Deep permanent pool areas are defined as four feet or greater; aquatic bench max depth is 18 in below normal pool.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "arlington-tx", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/arlington-tx/", "data_url": "https://stormwateratlas.com/data/manuals/arlington-tx.json", "document_metadata": { "jurisdiction_name": "City of Arlington", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Design Criteria Manual", "version_or_edition": "Updated April 1, 2020", "adoption_or_effective_date": "2020-04-01", "last_revised_date": "2020-04-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Section 5.10 Post Construction Stormwater Quality. Detention/retention ponds must be in public drainage easements where required.", "peak_flow_calculation_method": [ "100-year fully developed floodplain easement criteria for natural streams", "Flood study and detention technical review", "Detention/retention pond design criteria within DCM drainage sections" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Retention ponds", "Post-construction stormwater quality measures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Arlington", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Arlington", "page_or_section": "Purpose" }, { "field": "document_metadata.document_title", "excerpt": "Design Criteria Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Updated April 1, 2020", "page_or_section": "City webpage / cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "April 1, 2020", "page_or_section": "Update note" }, { "field": "document_metadata.last_revised_date", "excerpt": "April 1, 2020", "page_or_section": "Update note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Design Criteria Manual", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year fully developed floodplain", "page_or_section": "Drainage easements" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Post Construction Stormwater Quality", "page_or_section": "Section 5.10" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Detention/Retention Ponds", "page_or_section": "Drainage criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention/Retention Ponds", "page_or_section": "Drainage criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "detain the first 1-inch of runoff from the drainage area to be released over at least 24 hours but not more than 48 hours", "page_or_section": "Section 5.9 Stormwater Storage Facility, page 5-34 (114)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Dry storage facilities must be designed to release their full capacity over at least 24 hours but not more than 48 hours", "page_or_section": "Section 5.9 Stormwater Storage Facility, page 5-34 (114)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Dry storage facilities must be designed to release their full capacity over at least 24 hours but not more than 48 hours", "page_or_section": "Section 5.9 Stormwater Storage Facility, page 5-34 (114)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the first 1-inch of runoff from the drainage area to be released over at least 24 hours but not more than 48 hours", "page_or_section": "Section 5.9 Stormwater Storage Facility, page 5-34 (114)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The pond shall be a minimum of 4 feet deep", "page_or_section": "Section 5.9.C Retention ponds and amenity ponds, page 5-34 (114)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "minimum vegetated swale slope is 2%", "page_or_section": "Section 5.7.5.F Flumes and Vegetated Swales, page 5-26 (106)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Vegetated swale - maximum grade is 2%", "page_or_section": "Section 5.10.3.D Allowable Post-Construction BMPs, page 5-37 (117)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Arlington DCM Apr 2020 is multi-discipline; stormwater is one chapter — confirm WQ sizing details in Section 5.10. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.arlingtontx.gov/files/assets/city/v/2/public-works/documents/design-criteria-manual/arlington-design-criteria-manual.pdf", "landing_page_url": "https://www.arlingtontx.gov/City-Services/Transportation-Streets-Traffic/Streets-and-Traffic/Engineers-Builders-Contractors/Design-Criteria-Manual", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "arlington-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:27:49.740Z", "enrich_model": "composer-2.5:run-e17a4a33-be6f-4875-b234-93ea530e863c", "enrich_notes": "Post-construction BMP numeric criteria in Section 5.9–5.10; detailed BMP sizing defers to NCTCOG iSWM Technical Manual. WQ credit ties forebay detention of first 1 in. runoff to 24–48 h release. Retention/amenity ponds minimum permanent depth 4 ft. Vegetated swales capped at 2% grade; minimum vegetated swale slope 2% in flume/swale section.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "asheville-nc", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/asheville-nc/", "data_url": "https://stormwateratlas.com/data/manuals/asheville-nc.json", "document_metadata": { "jurisdiction_name": "City of Asheville", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (city MS4 / MDC)", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Combined SCM design volume handles the required storm depth for the applicable NCDEQ stormwater program (e.g., 1\" under 15A NCAC 02H .1021(6) for non-coastal HQW/ORW runoff treatment).", "peak_flow_calculation_method": [ "NCDEQ MDC outlet erosion protection for 10-year peak" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "SCM devices per 15A NCAC 02H .1051–.1062" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" }, { "field": "practice_mentions.bioretention", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.swale", "excerpt": "vegetated swales, level spreader-filter strips, and berms", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.wet_pond", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NCDEQ Design Manual (Cary/Wilmington pattern). City portal PDF may be 403-blocked.", "fields_not_found": [] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.ashevillenc.gov/department/engineering/stormwater/", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "asheville-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:28:14.604Z", "enrich_model": "composer-2.5:run-a0792260-8bb8-4858-b9e8-22848a92de2c", "enrich_notes": "Corpus is NCDEQ C-0 General MDC only (pages 2–7); device-specific MDC in Part C / Rules .1051–.1062 not included. One-inch storm depth cited via 15A NCAC 02H .1021(6) for non-coastal HQW/ORW runoff treatment. Dewatering required qualitatively (MDC 6) with no max drawdown hours.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "atlanta-ga", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/atlanta-ga/", "data_url": "https://stormwateratlas.com/data/manuals/atlanta-ga.json", "document_metadata": { "jurisdiction_name": "City of Atlanta", "jurisdiction_level": "municipality", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (city adopts GSMM; Chapter 74 Art. X)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Atlanta adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "municipality — City of Atlanta", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — GSMM 2016 / Chapter 74 Art. X", "page_or_section": "Coverage note" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals... 2-year through the 25-year return frequency storm events", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater management systems shall be designed to retain or treat the runoff from 85% of the storms that occur in an average year, and reduce average annual post-development total suspended solids loadings by 80%. Averaged from rainfall events across the state of Georgia, this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events.", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "What is the SCS curve number for this sub-watershed", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters; Regenerative Stormwater Conveyance; Sand Filters; and Stormwater Planters/Tree Boxes", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv)", "page_or_section": "Atlas context / WQv method" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable standalone Atlanta design-manual PDF found; municipality coverage via GSMM 2016 (same approach as Fulton/DeKalb). Prefer city-specific PDF if published.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "atlanta-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:28:55.433Z", "enrich_model": "composer-2.5:run-45f7d681-6cb9-48cc-8353-e78d2ddb634a", "enrich_notes": "City adopts Georgia Stormwater Management Manual (GSMM 2016); Chapter 74 Art. X. WQv sized for 85% of average-year storms (1.2 in rainfall); first 1.0 in may be addressed via runoff-reduction BMPs to maximum extent practicable with possible WQv waiver if fully reduced; otherwise remaining runoff from 1.2-in event treated for ≥80% average annual TSS removal. No durable standalone Atlanta design-manual PDF in atlas; numeric SCM sizing not in provided text.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "augusta-me", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/augusta-me/", "data_url": "https://stormwateratlas.com/data/manuals/augusta-me.json", "document_metadata": { "jurisdiction_name": "City of Augusta", "jurisdiction_level": "municipality", "state_code": "ME", "document_title": "Maine Stormwater Management Design Manual, Volume III (capital MS4)", "version_or_edition": "May 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-05-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25 ], "water_quality_volume_method": "Treat the first 1 inch of runoff from impervious surfaces and 0.4 inch from landscaped areas.", "peak_flow_calculation_method": [ "Rational Method", "SCS TR-20", "SCS TR-55" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Detention Basins for Flooding Control", "Wet Ponds", "Vegetated Buffers", "Infiltration BMPs", "Filtration BMPs", "Separator BMPs", "LID Practices and Techniques" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Augusta capital MS4 follows Maine Stormwater Design Manual Vol III", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat the first 1 inch of runoff from impervious surfaces and 0.4 inch from landscaped areas", "page_or_section": "Maine Vol III" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "An underdrained soil filter must detain and filter a runoff volume equal to 1.0 inch times the subcatchment's impervious area plus 0.4 inch times the subcatchment's landscaped developed area.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A filter basin must drain dry in no less than 24 and no more than 48 hours.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The soil filter over the gravel underdrain pipe bedding must be at least 18 inches deep and must extend across the entire filter area.", "page_or_section": "Chapter 7.2, page 58" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The peak water quality storage depth should not exceed 6 inches over a bioretention basin filter.", "page_or_section": "Chapter 7.2, page 57" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Provide a long and narrow basin shape, with a minimum 2:1 length to width ratio (3:1 is best).", "page_or_section": "Chapter 4 Wet Ponds, page 22" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "A minimum slope of 2% is considered normal for extensive and simple intensive greening.", "page_or_section": "Chapter 7.6, page 77" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Maine Stormwater Management Design Manual Volume III.", "fields_not_found": [] }, "source": { "document_url": "https://www.maine.gov/dep/land/stormwater/stormwaterbmps/vol3/volume%20III%20May%202016.pdf", "landing_page_url": "https://www.maine.gov/dep/land/stormwater/stormwaterbmps/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "augusta-me.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 2, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:30:04.085Z", "enrich_model": "composer-2.5:run-c8ea5725-b38d-4be8-8adf-e597ca65693c", "enrich_notes": "WQv sizing is explicit as 1.0 inch on impervious plus 0.4 inch on landscaped developed area (Atlas and Ch. 7.1/7.2/7.4). SHWT separation is stated as 12 inches (1 foot) for detention basins, bioretention, and subsurface sand filters, and 18 inches for grassed underdrained soil filters—no single manual-wide minimum was applied. Gravel wetland target detention is a 24–48 hour range. Pervious surface text gives infiltration bounds (<2.41 in/hr, >0.04 in/hr) and 1 inch+ storage capacity, not a single storage section depth. Proprietary systems use Maine DEP approval letters (Appendix B), not TAPE/NJCAT by name.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "aurora-co", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/aurora-co/", "data_url": "https://stormwateratlas.com/data/manuals/aurora-co.json", "document_metadata": { "jurisdiction_name": "City of Aurora", "jurisdiction_level": "municipality", "state_code": "CO", "document_title": "Storm Drainage Design and Technical Criteria", "version_or_edition": "January 2026", "adoption_or_effective_date": "2026-01", "last_revised_date": "2026-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Detention and water quality policies (Section 3.13). Incorporates Mile High Flood District (MHFD) Urban Storm Drainage Criteria Manual for criteria not in this Manual. Water quality SCMs and MEP facility certification requirements.", "peak_flow_calculation_method": [ "Rational Method runoff coefficients (Section 5.3.2)", "Detention sizing and variance criteria (Section 3.13)", "Hierarchy: Aurora Manual first, then MHFD Volumes 1–3" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Water quality stormwater control measures (SCMs)", "MHFD-referenced treatment BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Aurora (CoA)", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Aurora", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "Aurora City Code Section 138-363", "page_or_section": "Purpose" }, { "field": "document_metadata.document_title", "excerpt": "Storm Drainage Design and Technical Criteria", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "January 2026", "page_or_section": "Cover / footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "January 2026", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "January 2026", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Mile High Flood District's (MHFD) Urban Storm Drainage Criteria Manual", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "detention / storm frequencies", "page_or_section": "Design criteria chapters" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "When Detention and/or Water Quality is Required", "page_or_section": "Section 3.13.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Runoff Coefficients for Rational Method", "page_or_section": "Section 5.3.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Water Quality SCMs", "page_or_section": "Section 2.7 / 3.13" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The design storm depth corresponding to the WQE is 0.60 inches for the Denver metropolitan region.", "page_or_section": "§3 definitions (page 89, aurora-co-c0125)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "FSD is based on detaining the EURV and releasing it over approximately 72 hours (unless reduced time required in airport zone).", "page_or_section": "§10.4 Full Spectrum Detention (page 208, aurora-co-c0231)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Zone 2 ranges from 12 to 32 hours depending on the type of SCM and must drain 97% of the EURV and WQCV within 72 hours", "page_or_section": "§10.4 (page 210, aurora-co-c0231)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the detention facility storage area must be at least 2 feet above the seasonal high groundwater elevation.", "page_or_section": "§10.9.1 Grading Requirements (page 222, aurora-co-c0243)" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Performance must be verified through Technology Assessment Protocol–Ecology (TAPE) with the HRMF having achieved a General Use Level Designation (GULD) for Basic Treatment.", "page_or_section": "Table 11-3 MTDs (page 245, aurora-co-c0263)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Zone 1 provides the WQCV and is released over the drain time (12 to 40 hours) corresponding to the type of SCM.", "page_or_section": "§10.4 Figure 10-2 narrative (page 209, aurora-co-c0231)" }, { "field": "practice_mentions.bioretention", "excerpt": "Impervious Area < 2 acres: water quality via infiltration/filtration SCM; no EDB. Use bioretention, sand filter, or permeable pavement.", "page_or_section": "Table 11-1 (page 239, aurora-co-c0258)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Aurora SDDTC Jan 2026; return periods inferred from typical MHFD/Aurora practice — confirm exact list from hydrology chapter.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://cdnsm5-hosted.civiclive.com/UserFiles/Servers/Server_1881137/File/Business%20Services/Development%20Center/Water%20%26%20Other%20Utilities/2026%20SDDTC%20FINAL%20(January%202026).pdf", "landing_page_url": "https://www.auroragov.org/", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "aurora-co.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "TAPE", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:30:39.241Z", "enrich_model": "composer-2.5:run-a2d38eee-77cd-4bf0-9609-c4dd37397f18", "enrich_notes": "CoA nests WQCV in EURV and 100-year FSD per MHFD Vol. 2 Ch. 12. WQCV sizing uses regression with WQE 0.60 in. (80th percentile). Zone 1 WQCV drain 12–40 hr by SCM type; Zone 2 EURV 12–32 hr; 97% of WQCV+EURV within 72 hr except airport zones (FAA 48 hr, DEN 40 hr within 10,000 ft). Detention storage bottom min 2 ft above seasonal high groundwater. New constructed wetland and retention ponds prohibited; EDB requires ≥2 impervious acres. Tier 2 sites <2 ac impervious: bioretention, sand filter, or permeable pavement only (no EDB). Detailed SCM dimensions referenced to MHFD Vol. 3 Ch. 4 fact sheets and workbooks.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "austin-tx-ecm", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/austin-tx-ecm/", "data_url": "https://stormwateratlas.com/data/manuals/austin-tx-ecm.json", "document_metadata": { "jurisdiction_name": "City of Austin", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "ENVIRONMENTAL CRITERIA MANUAL", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "vegetative filter strips", "rain gardens", "biofiltration ponds", "irrigation", "infiltration", "sedimentation/filtration ponds", "SOS ponds" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Austin's Land Development Code", "page_or_section": "Section 1.3.0, Page 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Austin's Land Development Code", "page_or_section": "Section 1.3.0, Page 1" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL CRITERIA MANUAL", "page_or_section": "Header, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100 year floodplain", "page_or_section": "Section 1.3.0, Page 1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "vegetative filter strips, rain gardens, biofiltration ponds, and areas used for irrigation or infiltration of stormwater", "page_or_section": "Section 1.5.3 H, Page 5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "sedimentation/filtration ponds for the redeveloped area or an equivalent area on the site", "page_or_section": "Appendix Q-6, Page 20" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "[…] F. Detention Basins and Wet Ponds In-channel detention basins and in-channel wet ponds can be located within the Critical Water Quality Zone if the requirements of Sections 25-8-364 (Floodplain Modification), 25-7 (Drainage), and other provisions 25-8 Subchapter A are", "page_or_section": "p. 4" }, { "field": "practice_mentions.bioretention", "excerpt": "vegetative filter strips, rain gardens, biofiltration ponds, and areas used for irrigation or infiltration of stormwater are allowed within the Critical Water Quality Zone", "page_or_section": "1.5.3 H. Green Water Quality Controls (page 5)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "areas used for irrigation or infiltration of stormwater are allowed within the Critical Water Quality Zone", "page_or_section": "1.5.3 H. Green Water Quality Controls (page 5)" }, { "field": "practice_mentions.wet_pond", "excerpt": "In-channel detention basins and in-channel wet ponds can be located within the Critical Water Quality Zone", "page_or_section": "1.5.3 F. Detention Basins and Wet Ponds (page 4)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "porous pavement designed in accordance with Section 1.6.7 of this manual, limited to only pedestrian walkways and multi-use trails", "page_or_section": "1.8.1 C. Impervious cover calculations exclude (page 8)" }, { "field": "practice_mentions.sand_filter", "excerpt": "If the entire site is treated with sedimentation/sand filtration or an equivalent level of water quality control", "page_or_section": "OPTION 1 WORKSHEET / INSTRUCTIONS (pages 12-14)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "State code set to TX from the Municode landing path (/tx/austin) and filename; the ECM text excerpt did not spell out Texas. Return periods include 100-year from the floodplain references. Peak flow methods live in the separate Drainage Criteria Manual. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://mcclibraryfunctions.azurewebsites.us/api/ordinanceDownload/15306/905455/pdf", "landing_page_url": "https://library.municode.com/tx/austin/codes/environmental_criteria_manual", "retrieved_at": "2026-08-07T11:43:24.317Z", "original_filename": "austin-tx-ecm.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "permeable_pavement", "sand_filter", "wet_pond" ], "enriched_at": "2026-08-13T07:31:07.078Z", "enrich_model": "composer-2.5:run-9773fc8b-3a2d-431d-98d1-7e42e753e409", "enrich_notes": "Provided corpus emphasizes Critical Water Quality Zone setbacks, floodplain modification, pollutant load species, impervious-cover exclusions, and Barton Springs Zone mitigation worksheets—not BMP sizing. Rain gardens, biofiltration ponds, vegetative filter strips, infiltration/irrigation areas, detention/wet ponds, and porous pavement (ECM 1.6.7) are named; numeric design criteria are pointed to ECM Section 1.6.9.3 Control Measure Design, which is not in the excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bakersfield-ca", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/bakersfield-ca/", "data_url": "https://stormwateratlas.com/data/manuals/bakersfield-ca.json", "document_metadata": { "jurisdiction_name": "City of Bakersfield", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Kern County Development Standards — Division Four: Standards for Drainage (metro co-permittee basis)", "version_or_edition": "Division Four", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Drainage facilities designed for Intermediate Storm Design Discharge (ISDD ≈ 10-year) and Capital Storm Design Discharge (CSDD ≈ 100-year). Retention basins (sumps) and detention basins sized for design ponding depth/volume per Kern County standards; off-site CSDD/ISDD mitigation required for development.", "peak_flow_calculation_method": [ "Capital Storm Design Discharge (CSDD / 100-year)", "Intermediate Storm Design Discharge (ISDD / 10-year)", "Kern County hydrology methods (per bulletin/standards)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention basins (sumps)", "Detention / retardation basins", "Closed conduit systems and catch basins", "Culverts, bridges, at-grade crossings", "Constructed channels", "Street drainage" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "refers to the Department of the County of Kern with jurisdiction. 402.1.02 ALLUVIAL FAN: is a landform originating at an apex and characterized by high-velocity flows; active processes of erosion, sediment transport, and deposition; and unpredictable flow paths. 402-1.03", "page_or_section": "p. 2" }, { "field": "document_metadata.state_code", "excerpt": "County of Kern", "page_or_section": "§402 definitions" }, { "field": "document_metadata.document_title", "excerpt": "STANDARDS FOR DRAINAGE", "page_or_section": "Division Four header" }, { "field": "document_metadata.version_or_edition", "excerpt": "Division Four", "page_or_section": "Header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Kern County Development Standards Division Four", "page_or_section": "Coverage note" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Capital Storm Design Discharge (CSDD) ... referred to as the 100-year storm; Intermediate Storm Design Discharge (ISDD) ... referred to as the ten-year storm", "page_or_section": "§402-1.04 / §402-1.17" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "RETENTION BASIN: is a terminal storm water facility for the storage of runoff. Commonly referred to as a sump.", "page_or_section": "§402-1.24" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "CSDD and ISDD flows shall be calculated in accordance with the current Kern County", "page_or_section": "§402-3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Basin Design; Detention Basin Design; Closed Conduit Systems, Catch Basins", "page_or_section": "Division Four chapters" }, { "field": "max_drawdown_hours", "excerpt": "Retention basins shall not be permitted unless it can be demonstrated, to the satisfaction of the Director, that the basin will completely drain the design volume within seven (7) days.", "page_or_section": "Sec. 408-8.01, CHAPTER VIII (page 16)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "RETENTION BASIN: is a terminal storm water facility for the storage of runoff. Commonly referred to as a sump.", "page_or_section": "Sec. 402-1.24 Definitions (page 4)" }, { "field": "practice_mentions.extended_detention", "excerpt": "DETENTION BASIN: is a storm water facility designed to affect flood hydrograph peak attenuation.", "page_or_section": "Sec. 402-1.11 Definitions (page 3)" }, { "field": "practice_mentions.extended_detention", "excerpt": "The design flow into the basin shall be the ISDD five-day runoff hydrograph.", "page_or_section": "Sec. 409-1, CHAPTER IX (page 17)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Kern County Division Four drainage standards used for Bakersfield metro / co-permittee coverage. City of Bakersfield may publish a separate Subdivision/Engineering Design Manual — prefer swapping if a durable city PDF is found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level" ] }, "source": { "document_url": "https://www.kernpublicworks.com/home/showpublisheddocument/10468/638385981778770000", "landing_page_url": "https://www.kernpublicworks.com/services/development/services/engineering-resources/development-standards/div-4-drainage", "retrieved_at": "2026-08-10T09:20:00.000Z", "original_filename": "bakersfield-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 168, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin" ], "enriched_at": "2026-08-13T07:32:08.064Z", "enrich_model": "composer-2.5:run-cb9b975c-43cb-497d-b296-1fef7d7645a0", "enrich_notes": "Kern County Division Four focuses on flood/quantity (ISDD ≈ 10-year, CSDD ≈ 100-year). Retention (sump) volume uses ISDD five-day rainfall from NOAA Atlas 14 Vol. 6 per Engineering Bulletin 11-02, not a separate WQv depth in inches. Detention/retardation basins follow ISDD five-day hydrograph; LID BMPs and manufactured treatment are not addressed in the provided excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "baltimore-md", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/baltimore-md/", "data_url": "https://stormwateratlas.com/data/manuals/baltimore-md.json", "document_metadata": { "jurisdiction_name": "City of Baltimore", "jurisdiction_level": "municipality", "state_code": "MD", "document_title": "Stormwater Management Minimum Requirements", "version_or_edition": "October 2019", "adoption_or_effective_date": "2019-10", "last_revised_date": "2019-10", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 10, 100 ], "water_quality_volume_method": "Qualitative control uses water quality volume and recharge volume per the 2000 Maryland Stormwater Design Manual (Revised), with ESD to the MEP. New development: treat 1.0 inch. Redevelopment: treat 0.5 inch, or remove 50% of impervious area, or a combination. Quasi-redevelopment: redevelopment rules for existing impervious plus new-development rules for added impervious.", "peak_flow_calculation_method": [ "Channel protection volume (CPv): 24-hour extended detention of the 1-year, 24-hour storm vs woods in good condition", "Overbank flood protection (Q10): control 10-year peak vs existing conditions", "Extreme flood (Q100): control 100-year peak vs existing conditions (required for inter-jurisdictional watersheds and noted flood hazard areas)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Environmental Site Design (ESD) practices (per MD Design Manual)", "Structural practices (per MD Design Manual)", "Alternative practices", "Off-site treatment (same 8-digit watershed, within City)", "Fee-in-lieu of treatment (DPW discretion after MEP)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Baltimore City DPW October 2019", "page_or_section": "Page 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Article 7, Division II of the City Code requires that land disturbance activities must have stormwater management plans approved by the Department of Public Works (DPW).", "page_or_section": "Page 1" }, { "field": "document_metadata.state_code", "excerpt": "comply with the 2000 Maryland Stormwater Design Manual (Revised)", "page_or_section": "Page 1" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Minimum Requirements", "page_or_section": "Page 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Baltimore City DPW October 2019", "page_or_section": "Page 1" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Baltimore City DPW October 2019", "page_or_section": "Page 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "Baltimore City DPW October 2019", "page_or_section": "Page 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The stormwater management plans must also comply with the 2000 Maryland Stormwater Design Manual (Revised)", "page_or_section": "Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Channel protection volume (CPV): 24-hour extended detention of a one-year storm... Overbank flood protection volume (Q10): control of the peak flow rate of a 10-year storm... Extreme flood volume (Q100): control of the peak flow rate of a 100-year storm", "page_or_section": "Page 4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "New development Treatment of 1.0 inch... Redevelopment Treatment of 0.5 inch; or 50% removal of impervious surface area; or Combination of both.", "page_or_section": "Table 1, Page 5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "CPV and Q10 are required in all areas, except if directly discharging to tidal areas. Q100 is required for inter-jurisdictional watershed and flood hazard areas noted in this document.", "page_or_section": "Table 1, Page 5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Proposed stormwater management must demonstrate ESD to the MEP... environmental site design (ESD) must be the first approach in stormwater management design, followed by structural practices then alternative practices.", "page_or_section": "Page 4" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "New development Treatment of 1.0 inch", "page_or_section": "Table 1, page 5 (baltimore-md-c0005)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Redevelopment Treatment of 0.5 inch; or 50% removal of impervious surface area; or Combination of both.", "page_or_section": "Table 1, page 5 (baltimore-md-c0005)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Channel protection volume (CPV): 24-hour extended detention of a one-year storm, 24- hour storm event comparing proposed conditions to the site in woods in good condition.", "page_or_section": "page 4 (baltimore-md-c0004)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "City supplement only (5 pages). Detailed BMP sizing is deferred to the Maryland Stormwater Design Manual (already ingested as md-state). Threshold: SWM required for sites exceeding 5,000 sq ft disturbance.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.baltimorecity.gov/media/document/swm-min-reqpdf", "landing_page_url": "https://www.baltimorecity.gov/publicworks/water-system-in-the-city/stormwater/stormwater-management-requirements", "retrieved_at": "2026-08-10T07:09:00.000Z", "original_filename": "baltimore-md.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T07:32:23.463Z", "enrich_model": "composer-2.5:run-eccc3ded-9fdc-445d-8d66-7866d8442c37", "enrich_notes": "Five-page City DPW supplement; qualitative control uses WQv and recharge volume per the 2000 Maryland Stormwater Design Manual (Revised). Table 1 also requires redevelopment treatment of 0.5 inch WQv (or 50% impervious removal or combination). Quasi-redevelopment splits rules between existing and added impervious. BMP sizing and SCM numeric criteria are deferred to the Maryland manual and MDE technical memos; ESD to MEP is required before structural or alternative practices, off-site treatment, or fee-in-lieu.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "baton-rouge-la", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/baton-rouge-la/", "data_url": "https://stormwateratlas.com/data/manuals/baton-rouge-la.json", "document_metadata": { "jurisdiction_name": "City of Baton Rouge / East Baton Rouge Parish", "jurisdiction_level": "municipality", "state_code": "LA", "document_title": "Stormwater Best Management Practices for East Baton Rouge Parish — Master Development Program", "version_or_edition": "July 2007", "adoption_or_effective_date": "2007-07", "last_revised_date": "2007-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Ten-year design storm runoff rate based on rainfall and land cover (method not further named)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention and Retention Systems (Dry Pond, Wet Pond, Pond Edge with Bulkhead, Pervious Paving with Manufactured Subsurface Storage)", "Infiltration Systems (Pervious Paving, Pervious Paving with Aggregate Subsurface Storage, Infiltration Device, Cistern)", "Filtration Systems (Bioswale, Stormwater Planter, Sand Filter Basin, Catch Basin Insert, Water Quality Wetlands, Rain Garden, Green Roof)", "Construction Phase BMPs (Site Clearing, Erosion Control, Sediment Control, Water Runoff Control, Good Housekeeping)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Baton Rouge - Parish of East Baton Rouge", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Baton Rouge - Parish of East Baton Rouge", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Made possible in part by grants from the Louisiana Department of Environmental Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Best Management Practices for East Baton Rouge Parish - Master Development Program", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "EAST BATON ROUGE MASTER DEVELOPMENT PROGRAM... City Parish Planning Commission", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the pre-development runoff rate and volume for a minimum ten-year design storm should be calculated.", "page_or_section": "Chapter 2, The Development Site" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The rate of stormwater runoff, such as in cubic feet per second (cfs) is a factor of the ten-year design storm rainfall and the land cover over which it flows.", "page_or_section": "Chapter 2, Runoff Rate and Volume" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The rate of stormwater runoff, such as in cubic feet per second (cfs) is a factor of the ten-year design storm rainfall and the land cover over which it flows.", "page_or_section": "Chapter 2, Runoff Rate and Volume" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention and Retention Systems... Infiltration Systems... Filtration Systems", "page_or_section": "Chapter 5 / Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Pond Wet Pond Pond Edge with Bulkhead Pervious Paving with Manufactured Subsurface Storage Infiltration Systems Pervious Paving Pervious Paving with Aggregate Subsurface Storage Infiltration Device Cistern Filtration Systems Bioswale Stormwater Planter 1 Permeable Stormwater Pl", "page_or_section": "p. 6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Site Clearing BMPs... Erosion Control BMPs... Sediment Control BMPs... BMPs to Control Water Runoff... Good Housekeeping Measures", "page_or_section": "Table of Contents, Chapter 3" }, { "field": "permeable_pavement_storage_depth_inches", "excerpt": "The soil excavated for the four-feet of subsurface storage system was used as fill under the building.", "page_or_section": "STORMWATER MANAGEMENT PLANNING PROCESS, page 30" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "pervious concrete which allows water to drain off the parking surface at a rate more rapid than any storm (up to 50 inches per hour)", "page_or_section": "STORMWATER MANAGEMENT PLANNING PROCESS, page 30" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry ponds, also known as detention ponds, are designed to hold water for a minimum time and then completely drain.", "page_or_section": "CHAPTER 5 STORMWATER BMPs, Dry Pond, page 38" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet ponds, also known as stormwater ponds or retention / detention ponds, are permanent bodies of water.", "page_or_section": "CHAPTER 5 STORMWATER BMPs, Wet Pond, page 38" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Pervious concrete was designed for all the parking spaces.", "page_or_section": "STORMWATER MANAGEMENT PLANNING PROCESS, page 30" }, { "field": "practice_mentions.bioretention", "excerpt": "Rain Gardens are depressed landscaped areas that detain and treat stormwater runoff.", "page_or_section": "FILTRATION SYSTEMS, Rain Garden, page 49" }, { "field": "practice_mentions.swale", "excerpt": "Bioswales act as filtration devices in place of typical swales.", "page_or_section": "FILTRATION SYSTEMS, Bioswale, page 44" }, { "field": "practice_mentions.sand_filter", "excerpt": "Sand Filter Basins are designed as a two chambered device with the first chamber designed for the settlement of large particles", "page_or_section": "FILTRATION SYSTEMS, Sand Filter Basin, page 47" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Constructed wetlands provide for a progressive cleaning of stormwater before it drains into surface water.", "page_or_section": "FILTRATION SYSTEMS, Water Quality Wetlands, page 49" }, { "field": "practice_mentions.green_roof", "excerpt": "Green roofs are designed to intercept rainwater that falls on a roof, allowing plants to filter and uptake the water.", "page_or_section": "FILTRATION SYSTEMS, Green Roof, page 50" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Catch Basin Inserts are manufactured devices used to capture settlement and debris from stormwater before flowing through the system.", "page_or_section": "FILTRATION SYSTEMS, Catch Basin Insert, page 48" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Planning/BMP guidance appendix for EBR Master Development Program (July 2007). Explicitly requires calculating pre-development runoff for a minimum ten-year design storm, but does not define a quantified water quality volume, named hydrologic method (e.g., Rational/TR-55), or required software. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.brla.gov/DocumentCenter/View/2288/Appendix-K---Stormwater-BMPs-for-EBRP-Master-Development-Program-PDF", "landing_page_url": "https://www.brla.gov/2693/Environmental-Landscape", "retrieved_at": "2026-08-08T10:20:00.000Z", "original_filename": "baton-rouge-la.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 48, "design_infiltration_rate_in_per_hr": 50, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:32:56.898Z", "enrich_model": "composer-2.5:run-f37fb2d5-70b5-4348-a4c3-974930aad68a", "enrich_notes": "Manual is planning/BMP overview (July 2007); requires pre-development runoff for a minimum ten-year design storm but does not define WQV depth or hydrologic method. Stormwater planters specify 18 in sandy loam topsoil and 4–12 in reservoir depth (planter, not mapped to single bioretention fields). Water Quality Wetland diagram labels open water 3–7 ft, deep marsh 1.5–3 ft, shallow marsh 0.5–1.5 ft, wet meadow 0–6 in (ecological zones, not a single wet-pond design depth). Pervious paving aggregate sub-base noted as 40% void space; no required SHWT separation or drawdown hours stated numerically.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "beatrice-ne", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/beatrice-ne/", "data_url": "https://stormwateratlas.com/data/manuals/beatrice-ne.json", "document_metadata": { "jurisdiction_name": "City of Beatrice, Nebraska", "jurisdiction_level": "municipality", "state_code": "NE", "document_title": "Drainage Criteria Manual", "version_or_edition": "August 2020", "adoption_or_effective_date": "2020-09-08", "last_revised_date": "2020-08", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 100 ], "water_quality_volume_method": "Water Quality Control Volume (WQCV) for sites disturbing ≥1 acre: new development uses the 80th-percentile rainfall event; redevelopment uses the 70th-percentile. Beatrice is Region C (East): P = 0.83 in (80th) / 0.62 in (70th). WQCV = P × (0.05 + 0.009 × %impervious) × treatment drainage area (acres) × (1/12) × 43,560. Flow-based BMPs use Qwq from the NRCS CN procedure on the 80th-percentile 24-hour event with Tc = 5 minutes (impervious area only). WQCV drain-down typically 24–40 hours (up to 72 hours when stacked with flood control).", "peak_flow_calculation_method": [ "Rational Method", "NRCS unit hydrograph / Curve Number method", "Modified Rational Method (not for storage facility design)" ], "required_hydrologic_hydraulic_software": [ "HY-8", "Hydraulic Toolbox", "HEC-RAS", "HEC-HMS", "Nebraska Department of Transportation Rational Method RMA Calculator" ], "approved_bmp_categories": [ "Vegetated Filter Strip", "Grass Swale", "Infiltration Trench", "Infiltration Basin", "Bioretention Basin", "Media Filter", "Sand Filter", "Extended Dry Detention", "Wet Detention Ponds", "Stormwater Wetland", "Underground Detention", "Pervious Pavement", "Proprietary Structural Treatment Controls", "Green Roofs", "Soil Conditioning", "Construction Erosion and Sediment Control BMPs", "Good Housekeeping BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "WHEREAS, the City of Beatrice (\"City\") became an MS4 Community", "page_or_section": "Adoption Resolution" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This manual applies within the corporate limits of the City and its extraterritorial jurisdiction.", "page_or_section": "Page 1, Section 1.1" }, { "field": "document_metadata.state_code", "excerpt": "BEATRICE, NEBRASKA", "page_or_section": "Adoption Resolution" }, { "field": "document_metadata.document_title", "excerpt": "That the Drainage Criteria Manual, dated August 2020, marked as Exhibit \"A\"... be and is hereby adopted.", "page_or_section": "Adoption Resolution, Section 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Drainage Criteria Manual, dated August 2020", "page_or_section": "Adoption Resolution" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "RESOLUTION PASSED AND ADOPTED this 8th day of September, 2020.", "page_or_section": "Adoption Resolution" }, { "field": "document_metadata.last_revised_date", "excerpt": "Drainage Criteria Manual, dated August 2020", "page_or_section": "Adoption Resolution" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Portions of the City of Lincoln Drainage Criteria Manual, the City of Omaha Regional Stormwater Design Criteria Manual was used in the development of this manual.", "page_or_section": "Introduction / related manuals discussion" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The minor drainage system design will be based on the 5-year (20% annual exceedance probability) design storm for residential areas and the 10-year (10% annual exceedance probability) design storm for", "page_or_section": "Section 1.4 / minor drainage system" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The 100-year return frequency storm (1% annual exceedance probability) shall be the major drainage system design storm for all new developments.", "page_or_section": "Major drainage system criteria" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Design storms equal to the 2-, 10- and 100-year frequency events shall be used in the design of detention and retention facilities.", "page_or_section": "Detention / retention criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For new development sites that have a land disturbance of one acre or greater, the WQCV shall be based on the 80th percentile rainfall event, at a minimum.", "page_or_section": "Page 107, Section 9.4.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For redevelopment sites that have land disturbance of one acre or greater, the WQCV shall be based on the 70th percentile rainfall event, at a minimum.", "page_or_section": "Page 107, Section 9.4.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "C (East) • Beatrice • Columbus • Fremont • Norfolk 0.83\" 0.62\"", "page_or_section": "Page 108, Table 9-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Qwq is the peak runoff from the design water quality volume rainfall event. This peak runoff equivalent shall be calculated using the Natural Resources Conservation Service (NRCS) Curve Number (CN) procedure. The calculation is based on the 80th percentile rainfall event depth by region, a 24-hour duration storm event, and a time of concentration of 5 minutes.", "page_or_section": "Page 109, Section 9.4.4.3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Peak runoff values shall be calculated by using either the rational method, NRCS unit hydrograph method, or rational or NRCS methodological software as appropriate.", "page_or_section": "Hydrology / peak runoff criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The NRCS Curve Number method shall be used to develop inflow and outflow hydrographs for the design of storage facilities. The Rational Method or Modified Rational Method shall not be used for design of storage facilities.", "page_or_section": "Detention / retention criteria" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Software available from the Federal Highway Administration such as HY-8 or Hydraulic Toolbox, the U.S. Army Corps of Engineers such as HEC-RAS or HEC-HMS, or state agencies such as the Nebraska Department of Transportation's Rational Method RMA Calculator are generally acceptable in their most recent versions", "page_or_section": "Page 6, Section 1.6 Software" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "e s BMP Type Omaha Lincoln NDOR UDFCD Vegetated Filter Strip X X X Grass Swale X X X Infiltration Trench X Infiltration Basin X Bioretention Basin X X X X Media Filter X Sand Filter X Extended Dry Detention X X X X Wet Detention Ponds X X X X Stormwater Wetland X X X X Undergro", "page_or_section": "p. 125" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Section 8.4 addresses Erosion and Sediment Control BMP, and Section 8.5 addresses Good Housekeeping BMPs.", "page_or_section": "Chapter 8" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "For facilities that function just for water quality control, the WQCV will be stored for a duration between 24 and 40 hours.", "page_or_section": "9.4.4.4, page 122" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "In this case, the facility shall be drained within 72 hours.", "page_or_section": "9.4.4.4, page 122" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The methodology for calculating the Water Quality Control Volume (WQCV) and/or Water Quality Volume Discharge Rate (Qwq) is based on average daily rainfall data applied to three zones across the state (Table 9-1).", "page_or_section": "Chapter 9 Design Criteria, page 118" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration tests shall be done to determine the local infiltration rates if infiltration is a critical part of the Structural BMP facility.", "page_or_section": "9.4.4.4, page 122" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention Basin", "page_or_section": "Table 9-3, page 113" }, { "field": "practice_mentions.swale", "excerpt": "Grass Swale", "page_or_section": "Table 9-3, page 113" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Pervious Pavement", "page_or_section": "Table 9-3, page 113" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Proprietary Structural Treatment Controls", "page_or_section": "Table 9-3, page 113" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Municipal manual adopted Sept 8, 2020 (August 2020 edition). Aligns with Omaha/Lincoln/NDOT regional guidance for post-construction BMPs; WQCV depths for Beatrice are Region C East values in Table 9-1. Software list is \"generally acceptable\" examples, not exclusive mandates. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_parameters.wqv_depth_inches" ] }, "source": { "document_url": "https://www.beatrice.ne.gov/media/400fdosn/drainage_criteria_manual.pdf", "landing_page_url": "https://www.beatrice.ne.gov/", "retrieved_at": "2026-08-08T10:30:00.000Z", "original_filename": "beatrice-ne.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:33:44.146Z", "enrich_model": "composer-2.5:run-4122e60f-2076-4b34-9dfd-033e6c2fb727", "enrich_notes": "Chapter 9 sizes all listed BMPs to WQCV or Qwq (Section 9.4); detailed geometry and media depths are delegated to Omaha, Lincoln, NDOR, and UDFCD manuals (Section 9.6). WQCV release/storage duration is stated as 24–40 hours for water-quality-only facilities and drain within 72 hours when flood-control volumes are stacked (9.4.4.4). Qwq uses NRCS CN on the 80th-percentile regional rainfall depth, 24-hour storm, Tc = 5 minutes, impervious area only (9.4.4.3). Table 9-1 rainfall depths by region are referenced but not reproduced in the supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "beaumont-tx", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/beaumont-tx/", "data_url": "https://stormwateratlas.com/data/manuals/beaumont-tx.json", "document_metadata": { "jurisdiction_name": "City of Beaumont / Jefferson County Drainage District No. 6", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Drainage Criteria Manual", "version_or_edition": "July 2025 Update", "adoption_or_effective_date": "2025-07-01", "last_revised_date": "2025-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "DD6 Drainage Criteria Manual focuses on peak-flow conveyance and on-site detention/retention using Atlas 14 rainfall (10-/25-/50-/100-year 24-hour distributions). Explicit post-construction WQv depth is not a primary DD6 criterion; City of Beaumont MS4 SWMP is separate. Where City of Beaumont criteria conflict with DD6, the more restrictive applies.", "peak_flow_calculation_method": [ "NOAA Atlas 14 precipitation-frequency (Texas Vol.11)", "Rational Method intensity coefficients (Table 4-3)", "On-site detention/retention routing (Ch.10)", "10-/25-/50-/100-year peak flow conveyance within and from developments" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "On-site detention basins", "Retention facilities", "Open channels / storm sewers", "Outfall / energy dissipation" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Jefferson County Drainage District No. 6 Drainage Criteria Manual (July 2025 Update)", "page_or_section": "Cover" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-year, 25-year, 50-year, and 100-year peak flow runoff within the boundaries of subdivisions and developments", "page_or_section": "Drainage Regulation intent" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "hypothetical 24-hr, 10-year, 25-year, 50-year, and 100-year storm rainfall distribution based on the Atlas 14 report", "page_or_section": "Hydrologic Design Criteria" }, { "field": "practice_mentions.extended_detention", "excerpt": "A detention facility is designed to store the increased runoff while releasing discharges continuously at acceptable rates through flow-limiting outlet structures", "page_or_section": "10. On-Site Detention and Retention Criteria, page 28" }, { "field": "practice_mentions.wet_pond", "excerpt": "A retention facility, often designed to have a permanent pool, is designed to store runoff and release it after the passage of peak flows.", "page_or_section": "10.1 General, page 28" }, { "field": "practice_mentions.swale", "excerpt": "E. Curb cut overflow and swale overflow.", "page_or_section": "7.3 Design Schematics, page 24" }, { "field": "practice_mentions.swale", "excerpt": "A swale ditch is to be constructed just beyond the outside edge of the maintenance berm to convey water to downspouts", "page_or_section": "10.5 District Maintenance of Subdivision Detention Basins, page 30" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Drainage/detention criteria manual — limited explicit WQv; confirm Beaumont city post-construction water-quality standards separately.", "fields_not_found": [] }, "source": { "document_url": "https://dd6.org/wp-content/uploads/2025/07/Drainage-Criteria-Manual-Update-2025-FINAL-7-1-2025.pdf", "landing_page_url": "https://dd6.org/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "beaumont-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:34:10.752Z", "enrich_model": "composer-2.5:run-4524396f-7f82-4795-930d-3625f5ac84e7", "enrich_notes": "Jefferson County DD6 Drainage Criteria Manual (July 2025) emphasizes net-zero increase in runoff for impervious additions greater than 0.25 acres, on-site detention with flow-limiting outlets, and retention (often with permanent pool). Atlas 14 rainfall referenced for master drainage plans. Provided excerpts contain peak-flow, outfall, and conveyance criteria—not post-construction WQv depth or SCM sizing parameters. City of Beaumont MS4 standards may apply separately where more restrictive.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bellevue-wa", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/bellevue-wa/", "data_url": "https://stormwateratlas.com/data/manuals/bellevue-wa.json", "document_metadata": { "jurisdiction_name": "City of Bellevue", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Storm and Surface Water Engineering Standards", "version_or_edition": "January 2023", "adoption_or_effective_date": "2023-01-01", "last_revised_date": "2023-01-01", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Implements Ecology DOE Manual-aligned Minimum Requirements #1–#9 for new/redevelopment (site plans, construction SWPPP, source control, natural drainage, on-site stormwater management, runoff treatment, flow control, wetlands protection, O&M). Flow control and infiltration/detention facility standards in Chapters D6–D7; LID infeasibility criteria in appendices.", "peak_flow_calculation_method": [ "Minimum Requirement #7 Flow Control (duration matching per DOE Manual)", "Detention facility design standards", "Infiltration system design / feasibility checklist", "Flow control exemptions for Ecology-approved receiving waters" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "On-site stormwater management / LID BMPs", "Runoff treatment BMPs", "Flow control detention facilities", "Infiltration systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF BELLEVUE UTILITIES DEPARTMENT", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CITY OF BELLEVUE", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "listed in Chapter D1-04 of this manual, including preparation of a stormwater site plan, control of site construction stormwater, source control, preservation of natural discharge location, wetland protection and operation and maintenance. Each of the seven steps is descr", "page_or_section": "p. 16" }, { "field": "document_metadata.document_title", "excerpt": "STORM AND SURFACE WATER ENGINEERING STANDARDS", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "January 2023", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "January 2023", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "January 2023", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "in accordance with the DOE Manual / Storm and Surface Water Utility Code Chapter 24.06", "page_or_section": "D1-01.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "MINIMUM REQUIREMENT #6 - RUNOFF TREATMENT / #5 - ON-SITE STORMWATER MANAGEMENT", "page_or_section": "D1-04.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "MINIMUM REQUIREMENT #7 - FLOW CONTROL", "page_or_section": "D1-04.2(G)" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "FLOW CONTROL - DETENTION FACILITIES / INFILTRATION SYSTEMS", "page_or_section": "D6 / D7" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "General - The base of all infiltrating BMPs shall be at least 5 feet (with reductions allowed for certain smaller BMPs) above the seasonal high-water mark", "page_or_section": "D5-03.2.3 Step 3, page 187" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bioretention – 1 foot or 3-foot minimum separation from the bottom of a bioretention installation, depending upon the drainage area size", "page_or_section": "D5-03.2.3, page 188" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Permeable Pavement – 1-foot below the bottom of the base course for a permeable pavement (per BMP T5.15 – Infeasibility Criteria in the DOE Manual).", "page_or_section": "D5-03.2.3, page 188" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "For portions of the site where the measured infiltration rate is less than 0.3 inches per hour, no further infiltration feasibility evaluation is required.", "page_or_section": "D5-03.2.4, page 189" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "In no case shall the design infiltration rate exceed 10 inches per hour.", "page_or_section": "Appendix D10.2.3, page 310" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "2023 standards used (2025/2026 also published); Ecology DOE Manual equivalent framework.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://bellevuewa.gov/sites/default/files/media/pdf_document/2023/Storm%20Engineering%20Standards%202023%28PDF%29.pdf", "landing_page_url": "https://bellevuewa.gov/city-government/departments/utilities/utilities-projects-plans-standards/utilities-codes-and-standards/surface-water-engineering-standards", "retrieved_at": "2026-08-10T08:48:28.515Z", "original_filename": "bellevue-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:34:41.260Z", "enrich_model": "composer-2.5:run-f07fc923-fca2-4e5d-977d-d471a98ef003", "enrich_notes": "Bellevue 2023 standards defer detailed BMP sizing to Ecology DOE Manual (Vol III–V); local text emphasizes infiltration feasibility (PIT testing, correction factors), vertical separation by BMP type (general 5 ft to SHGW with 1–3 ft reductions for bioretention, permeable pavement, downspout infiltration), measured rate <0.3 in/hr infeasibility, design infiltration rate capped at 10 in/hr, rain garden/bioretention minimum 5% of tributary area, and Table 5.4 MR #5–7 BMP applicability.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bellingham-wa", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/bellingham-wa/", "data_url": "https://stormwateratlas.com/data/manuals/bellingham-wa.json", "document_metadata": { "jurisdiction_name": "City of Bellingham", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Management Manual for Western Washington (Ecology 2024; city MS4)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "Adopts Ecology SWMMWW Minimum Requirements including runoff treatment and flow control; continuous simulation (WWHM/HSPF) sizes flow control. Local stormwater code supplements SWMMWW.", "peak_flow_calculation_method": [ "Continuous Simulation Models", "WWHM / HSPF", "Single Event Hydrograph Method" ], "required_hydrologic_hydraulic_software": [ "WWHM", "HSPF" ], "approved_bmp_categories": [ "Flow Control BMPs", "Runoff Treatment BMPs", "LID BMPs", "Source Control BMPs", "Infiltration / bioretention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Bellingham MS4 follows Ecology SWMMWW", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — Ecology SWMMWW 2024", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Document that the maximum ponded depth from the infiltration BMP can infiltrate through the infiltration BMP surface within 48 hours.", "page_or_section": "Volume V - Chapter 5 - Page 823" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "UIC wells are designed to completely drain ponded runoff within 48 to 72 hours after flow to the UIC well has stopped.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The minimum vertical separation is 5 feet between the base of a UIC well and the highest elevation between the seasonal high groundwater table, bedrock, hardpan, or other low-permeability layer.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of BMP T7.10: Infiltration Ponds or BMP T7.20: Infiltration Trenches shall be ≥ 5 feet above the seasonal high-water mark, bedrock (or hardpan) or other low permeability layer.", "page_or_section": "Volume V - Chapter 5 - Page 823" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The \"Default\" and \"Custom\" BSM depth must be 18 inches to provide Runoff Treatment and good growing conditions for selected plants.", "page_or_section": "Volume V - Chapter 5 - Page 921" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Ecology SWMMWW (Everett/Olympia pattern). City may publish a local drainage manual separately.", "fields_not_found": [] }, "source": { "document_url": "https://www.cityofcamas.us/sites/default/files/fileattachments/community_development/page/9505/2024swmmww_6-14-24.pdf", "landing_page_url": "https://cob.org/services/environment/stormwater", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "bellingham-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:35:24.352Z", "enrich_model": "composer-2.5:run-9efb6a47-1077-4a27-8635-7600f4bea01e", "enrich_notes": "Ecology SWMMWW excerpts: infiltration drawdown check is 48 h ponded depth; UIC wells cite 48–72 h drain. SHWT separation varies by BMP (5 ft / 60 in general for infiltration ponds, trenches, and UIC presumptive; 3 ft / 36 in may be allowed with analysis; 1 ft / 12 in below permeable pavement lowest layer and small bioretention; 3 ft below bioretention for larger contributing areas). BSM default/custom media depth 18 in. Site infeasibility below 0.3 in/hr native Ksat; long-term design infiltration up to 3 in/hr; BSM end-of-life Ksat 12 in/hr for sizing. Wet pond permanent pool max depth concern above 8 ft (96 in). Permeable pavement treatment sand layers 6 in or 12 in; minimum surface slope 1–2%. Biofiltration swales on sites slope less than 6%.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bend-or", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/bend-or/", "data_url": "https://stormwateratlas.com/data/manuals/bend-or.json", "document_metadata": { "jurisdiction_name": "City of Bend", "jurisdiction_level": "municipality", "state_code": "OR", "document_title": "Eugene Stormwater Management Manual (Oregon municipal reference)", "version_or_edition": "2025", "adoption_or_effective_date": "2025-07-01", "last_revised_date": "2025-01-01", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Bend city design-standards portal returns 403. Using Eugene SWMM as Oregon municipal stormwater quality / flow-control reference: pollution reduction facilities sized to Water Quality Design Storm; flood and flow control per municipal code pattern.", "peak_flow_calculation_method": [ "Flood control design methodologies", "Flow control methodologies", "Water quality facility selection and design" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater quality / pollution reduction facilities", "Flow control facilities", "Flood control facilities", "Infiltration / UIC facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Bend — coverage via Eugene Stormwater Management Manual as Oregon municipal reference (not Bend-adopted)", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "When sized for flood control, infiltration facilities must infiltrate the Flood Control Design Storm Event within 30 hours.", "page_or_section": "2.2.2 Infiltration Facilities, page 34" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The required drawdown time for Drywells is 30 hours.", "page_or_section": "2.3.16 Drywell, page 72" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The required drawdown time for Soakage Trenches is 30 hours.", "page_or_section": "2.3.17 Soakage Trench, page 74" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the Drywell shall be at least 5 feet above the seasonal high groundwater table unless DEQ-approved pretreatment is provided.", "page_or_section": "2.3.16 Drywell, page 73" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the Soakage Trench drain rock layer shall be no less than 5 feet above seasonally high groundwater unless DEQ-approved pretreatment is provided.", "page_or_section": "2.3.17 Soakage Trench, page 75" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "A maximum infiltration rate of 2.5 inches per hour shall be allowed for design of extended filtration facilities based on the assumed infiltration rate through the growing medium.", "page_or_section": "2.4.2 Presumptive Approach, page 77" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The maximum depth of the pond shall not exceed 4 feet.", "page_or_section": "2.3.8 Ponds Design Requirements, page 51" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum length-to-width ratio is 3:1, at the maximum water surface elevation.", "page_or_section": "2.3.8 Ponds Design Requirements, page 51" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder — replace when Bend publishes a durable public design-standards PDF.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://www.eugene-or.gov/DocumentCenter/View/79289/2025-Stormwater-Management-Manual-with-Appendices", "landing_page_url": "https://www.bendoregon.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "bend-or.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 30, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:35:58.748Z", "enrich_model": "composer-2.5:run-49999a63-735f-41e8-9cb1-968b9029e118", "enrich_notes": "Corpus is Eugene SWMM 2025 used as Bend proxy. WQ sizing references Water Quality Design Storm volume (e.g., permanent pool = 2× WQDS runoff) but no WQ rainfall depth in inches in excerpts. Infiltration unsuitability cites groundwater <6 ft below surface (site constraint, not a universal SHWT separation for all BMPs). Drywell/soakage require 5 ft clearance above seasonal high groundwater (60 in). Drawdown 30 hr stated for infiltration (flood control), drywells, and soakage trenches. Presumptive extended filtration caps assumed infiltration through growing medium at 2.5 in/hr. Pond max depth 4 ft; min L:W 3:1 at max water surface.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "birmingham-al", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/birmingham-al/", "data_url": "https://stormwateratlas.com/data/manuals/birmingham-al.json", "document_metadata": { "jurisdiction_name": "City of Birmingham", "jurisdiction_level": "municipality", "state_code": "AL", "document_title": "Low Impact Development Handbook for the State of Alabama (city uses ADEM LID guidance)", "version_or_edition": "ADEM LID Handbook", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Bioretention and other SCMs sized for the water quality / first-flush volume per ADEM LID Handbook design guidance. Practices include bioretention cells, constructed stormwater wetlands, swales, and related LID SCMs.", "peak_flow_calculation_method": [ "ADEM LID Handbook hydrology appendix", "SCM-specific design procedures" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention (BRC)", "Constructed stormwater wetlands (CSW)", "Swales", "Other LID SCMs per handbook" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Birmingham uses ADEM LID Handbook", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "municipality — City of Birmingham", "page_or_section": "Coverage note" }, { "field": "document_metadata.document_title", "excerpt": "Low Impact Development Handbook", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Conservation Committee. 2009. Alabama Handbook for Erosion Control, Sediment Control, and Stormwater Management on Construction Sites and Urban Areas. Montgomery, AL. Brown, R.A., W.F. Hunt, and S.G. Kennedy. 2009. Designing Bioretention with an Internal Water Storage (IWS) Lay", "page_or_section": "p. 9" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "bioretention is normally designed for the water quality or first flush", "page_or_section": "Bioretention chapter" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Appendix A: Stormwater Hydrology", "page_or_section": "TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention; Constructed Stormwater Wetlands", "page_or_section": "TOC" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Bioretention is normally designed for the water quality or \"first flush\" event, typically the first 1\"-1.5\" of rainfall", "page_or_section": "Chapter 4.1 Bioretention, page 7" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A BRC is designed to hold approximately the first inch of runoff (first flush) from the entire drainage area.", "page_or_section": "Chapter 4.1 Bioretention Design Guidance, page 36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "BRCs should completely drain within 48 - 96 hours for the design rainfall volume captured.", "page_or_section": "Chapter 4.1 Bioretention, page 38" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "7. A properly designed BRC will drawdown in <96 hours.", "page_or_section": "Chapter 4.1 Bioretention, page 8" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table is at least 2' from the bottom of the cell", "page_or_section": "Chapter 4.1 Bioretention Site Selection, page 32" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table should be a minimum of 2' below the permeable pavement base", "page_or_section": "Chapter 4.3 Permeable Pavement, page 80" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Media depths above the underdrain layer must be at least 3' to use IWS", "page_or_section": "Chapter 4.1 Bioretention, page 35" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention Media 36 or pollutant dependent", "page_or_section": "Table 4.1.5, page 40" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding depths should be no more than 12\" for safety reasons.", "page_or_section": "Chapter 4.1 Bioretention Design Guidance, page 36" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The subbase layer ... typically ranges from 2 – 4' deep, but can be a minimum of 9\".", "page_or_section": "Chapter 4.3 Permeable Pavement (PC Components), page 82" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soils should have a minimum infiltration rate of 0.5\"/hr as determined by an infiltration test", "page_or_section": "Chapter 4.3 Permeable Pavement, page 80" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration swales that use a bioretention media should have a minimum infiltration rate of 0.5\"/hr.", "page_or_section": "Chapter 4.4 Swales, page 101" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "still retains stormwater within the wetland for a minimum of 48 hours.", "page_or_section": "Chapter 4.2 CSW Outlet Structure, page 57" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The longitudinal slope should not exceed 5% where possible.", "page_or_section": "Chapter 4.4 Swales, page 94" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Deep Pool ... 18 - 36\" Max allowable height (h)", "page_or_section": "Chapter 4.2 CSW Cross Section, page 57" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable Birmingham city design-manual PDF; coverage via ADEM LID Handbook. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://adem.alabama.gov/programs/water/waterforms/LIDHandbook.pdf", "landing_page_url": "https://adem.alabama.gov/programs/water/nps/lid.cnt", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "birmingham-al.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 96, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 36, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": 48, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:37:19.582Z", "enrich_model": "composer-2.5:run-b74e8047-3d21-42c3-8ca3-6152d80b23a0", "enrich_notes": "Birmingham coverage uses ADEM LID Handbook (Chapter 4). WQ sizing uses Discrete Curve Number Method; BRC example uses ~first inch of runoff with max 12 in ponding and 36 in media. BRC drawdown 48–96 hr (96 hr cap). CSW temporary pool drawdown target 2–5 days; minimum 48 hr retention in wetland. PP subbase/reservoir min 9 in (PC); 0.5 in/hr min soil infiltration for PP. Swale longitudinal slope not to exceed 5%. Green roofs listed on LID checklist only—no design depths in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bismarck-nd", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/bismarck-nd/", "data_url": "https://stormwateratlas.com/data/manuals/bismarck-nd.json", "document_metadata": { "jurisdiction_name": "City of Bismarck", "jurisdiction_level": "municipality", "state_code": "ND", "document_title": "Stormwater Design Standards Manual", "version_or_edition": "Approved August 22, 2017; Effective January 1, 2018", "adoption_or_effective_date": "2018-01-01", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 100 ], "water_quality_volume_method": "Water quality volume (Vwq) determined per Reference 5-2; new development uses prescriptive BMP sizing (Reference 5-1); redevelopment and retrofit must treat the first 0.5 inches of runoff from impervious areas, or demonstrate 80% TSS removal on an average annual basis via an approved alternative BMP method.", "peak_flow_calculation_method": [ "NRCS (SCS) Curve Number Method", "NRCS Unit Hydrograph Methods" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "InfoSWMM", "XP-SWMM / XP-STORM", "Storm & Sanitary Analysis (SSA)", "Bentley CivilStorm", "Civil 3D Hydrographs", "HEC-HMS" ], "approved_bmp_categories": [ "Detention Basins", "Infiltration BMPs", "Filtration BMPs", "Flow Through BMPs (proprietary mechanical treatment devices)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Bismarck Stormwater Design Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Municipal Public Works Improvements Bismarck, North Dakota” available from the office of the City Engineer. Stormwater Management Plan (SWMP) A written document detailing stormwater runoff characteristics for a defined area and the management of that runoff to mitigate advers", "page_or_section": "p. 15" }, { "field": "document_metadata.state_code", "excerpt": "Municipal Public Works Improvements Bismarck, North Dakota” available from the office of the City Engineer. Stormwater Management Plan (SWMP) A written document detailing stormwater runoff characteristics for a defined area and the management of that runoff to mitigate advers", "page_or_section": "p. 15" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Design Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "for activities constructed after January 1, 2018 that meet one or more of the following criteria: 1. Land disturbance greater than or equal to 3,000 square feet and less than 10,000 square feet, occurring on land with slopes of less than 12 percent; or", "page_or_section": "p. 21" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The goal of this section is to provide guidance on the design, performance, and analysis requirements of the City of Bismarck regarding Post-Construction Peak Discharge Compliance.", "page_or_section": "Section 4.0, Page 4-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Post-Construction runoff resulting from the 2-, 5-, 10-, and 100-year 24-hour rainfall events shall not exceed the runoff rate of the existing conditions.", "page_or_section": "Table 4-1, Page 4-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design BMPs to treat the first 0.5 inches of runoff from impervious areas. 80% Total Suspended Solids (TSS) removal on an average annual basis shall be achieved.", "page_or_section": "Table 5-1, Page 5-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "NRCS (SCS) Curve Number (CN) Method, NRCS Unit Hydrograph Methods & Time of Concentration Methods. The Rational Method is not an accepted methodology for Peak Discharge Control Compliance.", "page_or_section": "Section 4.4.1, Page 4-9" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "1. HydroCAD 2. InfoSWMM 3. XP-SWMM / XP-STORM 4. Storm & Sanitary Analysis (SSA) 5. Bentley CivilStorm 6. Civil 3D Hydrographs 7. HEC-HMS", "page_or_section": "Reference 4-4, Appendix 4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5.3.1 DETENTION BASINS ... 5.3.2 INFILTRATION BMPS ... 5.3.3 FLOW THROUGH BMPS", "page_or_section": "Section 5.3, Pages 5-5 to 5-7" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Are separated from seasonal high groundwater levels by greater than 5 feet", "page_or_section": "5.3.2 INFILTRATION BMPS, Page 5-6" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Located on sites with soils that drain freely and infiltrate 1 inches per hour or greater", "page_or_section": "5.3.2 INFILTRATION BMPS, Page 5-6" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Minimum length to width ratio is 3:1 as measured along the flow path from inlet to outlet", "page_or_section": "5.3.1 DETENTION BASINS, Page 5-5" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry Detention Basins (w/Extended Detention)", "page_or_section": "PCSMP Checklist SM-05, Section 5.2.2" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Flow Through BMPs are defined as proprietary mechanical treatment devices", "page_or_section": "5.3.3 FLOW THROUGH BMPS, Page 5-6" }, { "field": "practice_mentions.swale", "excerpt": "For above ground infiltration facilities (e.g., swales, basins)", "page_or_section": "Page 3-14" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Peak discharge storms, water quality requirements (0.5 in / 80% TSS), NRCS methods, and acceptable software are explicitly stated. Prescriptive Vwq sizing details are in appendix Reference 5-2, not reproduced in main text. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://bismarcknd.gov/DocumentCenter/View/30244/Stormwater-Design-Standards-Manual-PDF", "landing_page_url": "https://www.bismarcknd.gov/", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "bismarck-nd.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 1, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "manufactured_treatment", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:37:48.469Z", "enrich_model": "composer-2.5:run-8415b34d-2458-4926-b50a-83f3138eb81f", "enrich_notes": "Vwq sizing is in Appendix Reference 5-2 (not excerpted). Redevelopment 0.5 in / 80% TSS is atlas context only—not in corpus. Infiltration sites require ≥1 in/hr and >5 ft to SHWT; filtration/underdrain when <1 in/hr or within 5 ft of SHWT. WQ detention basins: 2 in min orifice, 3:1 L:W, forebay ≥10% area and 1 ft dead storage (dry). Drawdown compliance uses Reference 5-1/5-3; endpoint defined as within 3 in of lowest outlet. Flow-through devices need manufacturer certification vs Table 5-1.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "boca-raton-fl", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/boca-raton-fl/", "data_url": "https://stormwateratlas.com/data/manuals/boca-raton-fl.json", "document_metadata": { "jurisdiction_name": "City of Boca Raton", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "SFWMD Environmental Resource Permit Applicant's Handbook Volume II (Basis of Review)", "version_or_edition": "Effective July 4, 2010 (draft ERP Vol II mirror)", "adoption_or_effective_date": "2010-07-04", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "SFWMD ERP AH Vol II: wet detention volume for the first inch of runoff from the developed project (or 2.5 in over the basin for projects with ≥50% impervious / special cases per rule); dry detention = 75% of wet; retention = 50% of wet. Quantity: off-site discharge typically based on 3-day / 25-year storm unless local criteria are more stringent; 100-year / 3-day considered for flood protection / finished floors.", "peak_flow_calculation_method": [ "3-day / 25-year off-site discharge (default)", "100-year / 3-day flood considerations", "Retention / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Dry retention / detention", "Exfiltration trenches", "Swales / pretreatment", "Other SFWMD-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Boca Raton is within SFWMD and follows ERP Applicant's Handbook Vol II", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet detention volume shall be provided for the first inch of runoff", "page_or_section": "SFWMD Vol II water quality criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project, or the total runoff of 2.5 inches times the percentage of imperviousness, whichever is greater.", "page_or_section": "4.2.1 Volumetric Requirements, page 17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The required water quality system for one inch of runoff detention or one half inch of runoff retention in the master system for the total developed site.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.swale", "excerpt": "Onsite works such as swales and dikes shall be used to allow the passage of drainage from offsite areas to downstream areas.", "page_or_section": "3.8 Offsite Lands, page 14" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.3.1 Description, page 26" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The individual sites must provide the remainder (2.5\" x % impervious - one inch) which may be in exfiltration trench.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Subsurface exfiltration will be reviewed only on the basis of representative or actual test data submitted by the Applicant.", "page_or_section": "5.7.5.2 Subsurface, page 31" }, { "field": "practice_mentions.wet_pond", "excerpt": "Retention, detention, or both retention and detention in the overall system, including swales, lakes, canals, greenways, etc.", "page_or_section": "4.2.1 Volumetric Requirements (a), page 17" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry retention/detention areas shall have mechanisms for returning the groundwater level in the area to the control elevation.", "page_or_section": "5.3.3 Dry Retention/Detention Areas, page 26" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SFWMD ERP AH Vol II. Prefer city-specific drainage criteria if a durable public PDF appears.", "fields_not_found": [] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/draft_erp%20vol%20ii%20swerp%20ii_2104_10.pdf", "landing_page_url": "https://www.sfwmd.gov/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "boca-raton-fl.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:38:26.042Z", "enrich_model": "composer-2.5:run-06df9a65-0612-4c5d-a559-bb9d2e390791", "enrich_notes": "Corpus is SFWMD ERP Applicant's Handbook Vol. II (Aug 2014) via Boca Raton proxy. WQ volumetric rule: wet detention for first inch of developed runoff or 2.5 in × percent impervious, whichever is greater; alternatives include dry detention at 75% of wet volume and retention at 50% of wet (atlas summary—75%/50% not in supplied excerpts). Subdivision master systems: minimum 1 in runoff detention or 0.5 in retention in common master; remainder (2.5 in × % impervious − 1 in) may be exfiltration trench on lots; master cannot use exfiltration trench. Residential minimum drainage: ≥3/8 in/day surface or subsurface discharge so water surfaces lower within 12 days. Detention/control excavation capped at 6 ft below natural ground (§3.11(e)). Flood: building floors at 100-yr; roads/parking default 5-yr (1-day roads, 1-hr parking with exfiltration) if local criteria absent.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "boise-id", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/boise-id/", "data_url": "https://stormwateratlas.com/data/manuals/boise-id.json", "document_metadata": { "jurisdiction_name": "City of Boise", "jurisdiction_level": "municipality", "state_code": "ID", "document_title": "2019 Boise Stormwater Design Manual", "version_or_edition": "December 2019", "adoption_or_effective_date": "2019-12", "last_revised_date": "2019-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 50, 100 ], "water_quality_volume_method": "Treat storms up to 0.34-inch depth (City goal to fully treat at least 80% of annual storms); offsite discharges require 80% TSS removal; onsite infiltration systems retain the peak water quantity design volume.", "peak_flow_calculation_method": [ "Rational Method", "NRCS TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Sand Filters", "Biofiltration Swales and Grass Buffer Strips", "Oil Separators", "Catch Basin Inserts", "Infiltration Swales", "Infiltration Basins", "Seepage Beds", "Dry Detention Ponds", "Wet Extended Detention Ponds", "Evaporation Ponds", "Permeable Interlocking Concrete Pavers (PICP)", "Hydrodynamic Separators" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "within the jurisdiction of the city of Boise (City)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "within the jurisdiction of the city of Boise (City)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "Idaho Department of Water Resources (IDWR)", "page_or_section": "Section 2.5.C, Page 2-8" }, { "field": "document_metadata.document_title", "excerpt": "2019 Boise Stormwater Design Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "DECEMBER 2019", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "DECEMBER 2019", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "This MANUAL replaces the 2018 version of the MANUAL.", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Stormwater Design Manual (MANUAL) defines minimum standards, requirements, and procedures for the design, permitting, construction,and maintenance of drainage systems within the jurisdiction of the city of Boise (City) in accordance withthe City's Stormwater Management and Discharge Control Ordinance (ORDINANCE), Title 10, Chapter 6", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "pre- and post-development flow rate calculations for the 2, 5, 10, and 50-year storm events at sites less than10 acres... the 2, 5, 10, 50, and 100-year storm event are required at hillside development areas and sites greater than 10 acres", "page_or_section": "Section 2.5.B, Page 2-6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water quality treatment depth is based on the City's goal to fully treat at least 80% of the storms annually (i.e. 80% of daily storm events are estimated to have a depth of 0.34\" or less)... offsite stormwater discharges... require water quality treatment prior to discharge into the receiving drainage system to achieve an 80% reduction of Total Suspended Solids (TSS)", "page_or_section": "Table 2-1 and Section 2.5.C, Pages 2-6 to 2-8" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Calculation methodologies to determine the storm criteria include the Rational Method and the Natural Resources Conservation Service (NRCS) TR-55 method with a 24-hour design storm.", "page_or_section": "Section 2.5, Page 2-5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "infiltration of water quality volume Biofiltration Swale 80% Pretreatment for offsite discharges; sediment forebay included or flow path lengthened for additional sediment removal Grass Buffer (Filter) Strip 85% Pretreatment for offsite discharges; removal rate based on 150’ b", "page_or_section": "p. 19" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration facilities are required to empty within 48 hours following design storm events", "page_or_section": "Section 2.5.C Water Quality Design Criteria, page 18" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration basins do not maintain a permanent pool between storm events and should drain within 48 hours after a design storm event.", "page_or_section": "Section 3.2.E.2 Infiltration Basin, page 58" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "for all infiltration facilities, except seepage beds, a minimum 3‘ vertical separation distance from the bottom of the infiltration facility to the seasonal high ground water table", "page_or_section": "Section 3.2.E Setbacks and Separation Distances, page 54" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a minimum 3’ vertical separation distance from the bottom of the sand filter and the seasonal high ground water table", "page_or_section": "Section 3.2 (Sand Filters), page 34" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Open graded base reservoir (4” minimum thickness) shall conform to ASTM No. 57 stone", "page_or_section": "Section 3.2.G PICP, page 76" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Recommended maximum grade for slope swales is 1% to 2%.", "page_or_section": "Section 3.2.E.1 Infiltration Swales Design, page 56" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "For design purposes, PICP surface area is 100% permeable. Design infiltration rate is ten inches per hour per square foot of paver area.", "page_or_section": "Section 3.2.G PICP Design Criteria, page 76" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "BSM shall achieve a long-term, in-place infiltration rate of 5 inches/hour minimum, 8 inches/hour maximum.", "page_or_section": "Appendix C BSM Requirements, page 95" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Manual clearly states design storms, TR-55/Rational methods, 0.34-inch water quality depth with 80% TSS removal, and detailed BMP list in Table 2-3 and Chapter 3.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.partnersforcleanwater.org/media/1122/stormwaterdesignmanual12-2019.pdf", "landing_page_url": "https://www.cityofboise.org/departments/public-works/stormwater-and-drainage-control", "retrieved_at": "2026-08-08T01:05:00.000Z", "original_filename": "boise-id.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 4, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:38:46.692Z", "enrich_model": "composer-2.5:run-827e6e34-9681-40f2-8afc-14ab2bc0e4de", "enrich_notes": "Off-site discharges require 80% TSS removal (Table 2-3). Rational Method peak flows use 0.34 in/hr for 1 hr (intensity, not WQV depth in excerpts). Infiltration must empty within 48 hr (mosquito/quantity). SHWT: 3 ft (36 in) bottom-to-SHWT for most infiltration; seepage beds 10 ft (reducible to 5 ft with sand pretreatment); PICP sub-base to SHWT 2 ft (24 in); sand filters 3 ft to SHWT. BSM long-term infiltration 5–8 in/hr (Appendix C). PICP design infiltration stated as 10 in/hr. Swale bottom permeable soil ≥0.5 in/hr; sand window min 18 in ASTM C-33.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "boulder-co", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/boulder-co/", "data_url": "https://stormwateratlas.com/data/manuals/boulder-co.json", "document_metadata": { "jurisdiction_name": "City of Boulder", "jurisdiction_level": "municipality", "state_code": "CO", "document_title": "Urban Storm Drainage Criteria Manual Volume 3 (MHFD/UDFCD) — regional Front Range reference", "version_or_edition": "November 2015 (Vol.3 Ch.1)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches of precipitation within the MHFD/UDFCD boundary (≈80th percentile storm); remaining runoff after volume reduction treated through capture and slow release of the WQCV. City drainage portals often HTML/403 — Front Range MS4s commonly apply USDCM Volume 3.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grass Buffers / Swales", "Bioretention", "Permeable Pavement", "Extended Detention Basins", "Sand Filters", "Constructed Wetland / Retention Ponds", "Underground / Source Control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Boulder Front Range MS4 — coverage via MHFD/UDFCD Volume 3 WQCV", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches", "page_or_section": "USDCM Vol.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Within the UDFCD boundary, the WQCV is based on runoff from 0.6 inches of precipitation.", "page_or_section": "Chapter 1, page 11 (Common Stormwater Management Terms)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Regional MHFD criteria — prefer city-specific drainage criteria manual when a durable public PDF is available.", "fields_not_found": [] }, "source": { "document_url": "https://www.mhfd.org/files/7af5d4c2f/03_Chapter-1-Stormwater-Management.pdf", "landing_page_url": "https://bouldercolorado.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "boulder-co.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:39:44.349Z", "enrich_model": "composer-2.5:run-f3b2ccd7-5ffc-4a6f-951d-eb5e78a97ab1", "enrich_notes": "Corpus is USDCM Vol. 3 Chapter 1 (planning/regulatory); WQCV defined as runoff from 0.6 in. precipitation within UDFCD boundary (~80th percentile). Detailed BMP sizing appears in Chapters 3–5, not in provided excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "bridgeport-ct", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/bridgeport-ct/", "data_url": "https://stormwateratlas.com/data/manuals/bridgeport-ct.json", "document_metadata": { "jurisdiction_name": "City of Bridgeport", "jurisdiction_level": "municipality", "state_code": "CT", "document_title": "Connecticut Stormwater Quality Manual (city follows CT DEEP 2024 Manual)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-03-30", "last_revised_date": "2024-03-26", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV = (P)(R)(A)/12 where P = 1.3 inches (90th percentile rainfall event), R = volumetric runoff coefficient = 0.05 + 0.009(I).", "peak_flow_calculation_method": [ "NRCS Curve Number method", "Graphical Peak Discharge Method", "TR-20", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "WinTR-55", "HydroCAD", "TR-20" ], "approved_bmp_categories": [ "Pretreatment BMPs", "Infiltration BMPs", "Filtering BMPs", "Stormwater Pond BMPs", "Stormwater Wetland BMPs", "Water Quality Conveyance BMPs", "Stormwater Reuse BMPs", "Proprietary BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Bridgeport follows CT Stormwater Quality Manual 2024", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — CT DEEP 2024 Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "𝑊𝑊𝑊𝑊𝑊𝑊 = (𝑃𝑃)(𝑅𝑅)(𝐴𝐴) 12 where: WQV = water quality volume (cubic feet) P = 1.3 inches (90th percentile rainfall event) R = volumetric runoff coefficient = 0.05+0.009( I) I = post- development impervious area (percent) after application of non-structural LID site p", "page_or_section": "p. 53" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.3 inches (90th percentile rainfall event)", "page_or_section": "Chapter 4, page 53" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention system should completely drain in 48 hours or less after the end of the design storm", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration system ... should be located at least 3 feet above the SHGT and bedrock", "page_or_section": "Chapter 10, page 194" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered bioretention soil media should have a depth of 24 to 48 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for water quality storm: 12 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "design infiltration rate used for system sizing ... should be equal to 50% of the slowest observed field infiltration rate of the underlying soils or 0.5 inches per hour (1.0 feet per day) for the bioretention soil media, whichever value is lower", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention basin should completely drain within 48 hours after the end of a storm.", "page_or_section": "Chapter 13 – Dry Extended Detention Basin, page 467" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width o Minimum: 2 feet o Maximum: 8 feet", "page_or_section": "Chapter 13 – Wet Water Quality Swale, page 421" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green Roof Ground Slope Not Applicable (max 20% roof slope)", "page_or_section": "Chapter 8, Table 8-3, page 140" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via CT Stormwater Quality Manual 2024 (same pattern as other CT cities without local manuals).", "fields_not_found": [] }, "source": { "document_url": "https://portal.ct.gov/-/media/deep/water/water_quality_management/guidance/swm_mar_2024.pdf", "landing_page_url": "https://portal.ct.gov/DEEP/Water-Regulating-and-Discharges/Stormwater/Stormwater-Manual", "retrieved_at": "2026-08-10T09:45:18.917Z", "original_filename": "bridgeport-ct.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 20, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:40:02.112Z", "enrich_model": "composer-2.5:run-e1e9a7e0-a01a-4cc1-956e-d5e396021705", "enrich_notes": "Bridgeport follows CT DEEP 2024 Manual. WQV uses P=1.3 in (90th percentile). Suitability threshold for infiltration soils is 0.3 in/hr; bioretention sizing uses min(50% field rate, 0.5 in/hr). SHGT separation: 3 ft (36 in) recommended for infiltration bottoms; 2 ft (24 in) allowed in limited cases; unlined filtering requires bottom ≥1 ft above SHGT. QPA requires ≥18 in depth to SHGT (different from BMP bottom separation). Wet swale max ponding 12 in (mid) / 18 in (downstream end).", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "brownsville-tx", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/brownsville-tx/", "data_url": "https://stormwateratlas.com/data/manuals/brownsville-tx.json", "document_metadata": { "jurisdiction_name": "City of Brownsville", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Water Design Criteria Manual", "version_or_edition": "April 2019", "adoption_or_effective_date": "2019-04", "last_revised_date": "2019-04", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": "null Brownsville — prior CivicPlus PDFs wrong/scanned; San Antonio South TX pattern", "peak_flow_calculation_method": [ "Rational Method (Q = CIA) for drainage areas less than 200 acres", "Modified Rational Method for detention ponds with drainage areas of 20 acres or less", "Unit hydrograph method (preferably SCS Dimensionless Unit Hydrograph in HEC-HMS) for drainage areas 200 acres or greater and for detention ponds greater than 20 acres", "Snyder Unit Hydrograph", "Clark Unit Hydrograph", "NOAA Atlas 14 Volume 11 rainfall intensities / depths for San Antonio and ETJ" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS (preferred for SCS Dimensionless Unit Hydrograph / unit hydrograph modeling)" ], "approved_bmp_categories": [ "Onsite detention facilities (Regional Storm Water Management Program option)", "Fee in-lieu-of (FILO) detention participation", "Low Impact Development (LID) planning referenced in manual TOC" ] }, "evidence": [], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "South Texas municipal placeholder using San Antonio criteria — replace with city manual when available. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.sanantonio.gov/Portals/0/Files/CIMS/Services/UDC-Amendment-Drainage-Manual.pdf", "landing_page_url": "https://www.sanantonio.gov/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "brownsville-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T07:40:46.648Z", "enrich_model": "composer-2.5:run-25e6aa40-aa3c-42c6-a04f-693c0f66ac18", "enrich_notes": "Provided corpus for slug brownsville-tx is largely table of contents, figures/tables lists, San Antonio SWDCM April 2019 preface and hydrology introduction, and appendix checklist fragments. Chapter 13 lists detention and retention basins but no BMP numeric design criteria appear in the excerpts. Preface states the manual is for drainage facilities in and around the San Antonio area (Bexar County), consistent with atlas placeholder note.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "buffalo-ny", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/buffalo-ny/", "data_url": "https://stormwateratlas.com/data/manuals/buffalo-ny.json", "document_metadata": { "jurisdiction_name": "City of Buffalo / Buffalo Sewer Authority", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "Plan Review Guidance for Stormwater Management Design", "version_or_edition": "2019-10-15", "adoption_or_effective_date": null, "last_revised_date": "2019-10-15", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Designs must follow the most recent New York State Stormwater Management Design Manual (WQv and RRv targets). Green Infrastructure hierarchy (Green Code 7.3.4): conservation → bioretention/swales/porous pavement → green/blue roofs/cisterns → off-site GI → subsurface infiltration → underground detention. Combined/storm-relief sewer connections: post-construction 25-year peak ≤ pre-construction 2-year peak (TR-55 + NYSMDM).", "peak_flow_calculation_method": [ "Pre- and post-construction 1-, 10-, and 100-year storm calculations (storm-only connections)", "TR-55 + NYSMDM for combined/storm-relief: 25-year post ≤ 2-year pre peak", "WQv and RRv targets per NYSMDM" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Conservation of natural areas", "Bioretention / rain gardens / planters / bioswales", "Filter strips / constructed wetlands / porous pavement", "Green roof / blue roof / cisterns", "Subsurface infiltration / underground retention", "Underground detention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Buffalo Sewer Authority", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Buffalo Code / Green Code", "page_or_section": "Guidance" }, { "field": "document_metadata.state_code", "excerpt": "New York State Stormwater Design Manual", "page_or_section": "Criteria" }, { "field": "document_metadata.document_title", "excerpt": "Plan Review Guidance for Stormwater Management Design", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "191015 Plan Review SW Guidance", "page_or_section": "Filename" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "All designs must follow the criteria and standards contained in the most recent version of the New York State Stormwater Design Manual", "page_or_section": "Guidance" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-, 10-, and 100- year storm event / 25-year / 2-year", "page_or_section": "SWPPP requirements" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) and Runoff Reduction Volume (RRv) Targets", "page_or_section": "SWPPP A.6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "post-construction 25-year storm peak flows to the storm relief/ combined sewer system are less than or equal to pre-construction 2-year storm peak flows", "page_or_section": "Combined sewer criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bio-retention /Rain Gardens / Porous Pavement / Underground detention", "page_or_section": "Preference hierarchy" }, { "field": "practice_mentions.bioretention", "excerpt": "Bio-retention /Rain Gardens, Stormwater Planters, Vegetated Swale (bio-swale), Filter Strips, Constructed Wetlands, Porous Pavement", "page_or_section": "buffalo-ny-c0001 | page 1" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roof, Blue Roof, Cisterns", "page_or_section": "buffalo-ny-c0001 | page 1" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Tier 5 Subsurface infiltration or underground retention", "page_or_section": "buffalo-ny-c0001 | page 1" }, { "field": "enrich_notes", "excerpt": "All designs must follow the criteria and standards contained in the most recent version of the New York State Stormwater Design Manual.", "page_or_section": "buffalo-ny-c0001 | page 1" }, { "field": "enrich_notes", "excerpt": "6. Water Quality Volume (WQv) and Runoff Reduction Volume (RRv) Targets", "page_or_section": "buffalo-ny-c0002 | page 2" }, { "field": "enrich_notes", "excerpt": "post-construction 25-year storm peak flows to the storm relief/ combined sewer system are less than or equal to pre-construction 2-year storm peak flows", "page_or_section": "buffalo-ny-c0003 | page 3" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Short BSA local guidance; design numbers come from NYSMDM + combined-sewer peak criterion. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://buffalosewer.org/app/uploads/2020/01/191015-Plan-Review-SW-Guidance-Final.pdf", "landing_page_url": "https://buffalosewer.org/", "retrieved_at": "2026-08-10T08:30:22.061Z", "original_filename": "buffalo-ny.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:41:07.986Z", "enrich_model": "composer-2.5:run-ab7bcb5d-d5ad-4396-91ee-5cd8d7f996fc", "enrich_notes": "Buffalo BSA plan review defers design criteria to the most recent New York State Stormwater Design Manual (NYSMDM) for WQv and RRv; this document lists GI hierarchy (Green Code 7.3.4), limiting factors (contaminated soils, high groundwater, shallow bedrock, poor infiltration), and combined-sewer peak criterion (post-construction 25-year ≤ pre-construction 2-year via TR-55 + NYSMDM) but does not state numeric SCM sizing parameters.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "burlington-vt", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/burlington-vt/", "data_url": "https://stormwateratlas.com/data/manuals/burlington-vt.json", "document_metadata": { "jurisdiction_name": "City of Burlington", "jurisdiction_level": "municipality", "state_code": "VT", "document_title": "Vermont Stormwater Management Manual Volume I", "version_or_edition": "DRAFT March 1, 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-03-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 10, 100 ], "water_quality_volume_method": "WQv = (P)(Rv)(A) / 12, where P = 1.0 inch, Rv = 0.05 + 0.009(I).", "peak_flow_calculation_method": [ "NRCS Runoff methods", "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-55", "TR-20", "HECRAS" ], "approved_bmp_categories": [ "Pre-Treatment Practices", "Structural Stormwater Treatment Practices", "Non-Structural / Alternative Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Burlington MS4 follows Vermont Stormwater Management Manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.0 inch across Vermont", "page_or_section": "Section 2.2.4 WQTS, page 16" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "equivalent to the first inch of rainfall", "page_or_section": "Section 2.2.4 WQTS, page 16" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time of 48 hours", "page_or_section": "Dry Swale Design Summary, page 111" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time for Tv of 48 hours", "page_or_section": "Infiltration Design Summary, page 124" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "(2 days or 48 hours is the recommended maximum tf for bioretention)", "page_or_section": "Section 4.3.1 Bioretention, page 104" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Filter Bed Depth 24-48 inches", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max. Ponding Depth 12 inches", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate of 0.2 in/hr or greater if exfiltrating", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "infiltration rate (fc) of at least 0.2 inches per hour", "page_or_section": "Section 4.3.1.2 Bioretention Feasibility, page 101" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours", "page_or_section": "Shallow Wetland Design Summary, page 147" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours", "page_or_section": "Wet Pond Design Summary, page 159" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall have a bottom width between two and eight feet", "page_or_section": "Section 4.3.2.5, page 117" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Open channels constructed without check dams shall have a maximum longitudinal slope of 2%", "page_or_section": "Section 4.3.2.2, page 114" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Vermont Stormwater Management Manual (Montpelier pattern).", "fields_not_found": [] }, "source": { "document_url": "http://legislature.vermont.gov/Documents/2016/WorkGroups/House%20Fish%20and%20Wildlife/Stormwater%20Manual%20Revisions/W~Kevin%20Burke~Draft%20Stormwater%20Manual%20Revisions%20DEC~3-22-2016.pdf", "landing_page_url": "https://www.burlingtonvt.gov/DPW/Stormwater", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "burlington-vt.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.2, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:42:15.190Z", "enrich_model": "composer-2.5:run-c000a672-837e-4649-aee0-5b34dfd3a3c8", "enrich_notes": "WQv uses P=1.0 in and Rv=0.05+0.009(I); 90th percentile event described as first inch of rainfall; minimum 0.2 watershed-inch WQV for low impervious pervious runoff. SHGWT separation is conditional (1 ft, 2 ft, or 3 ft by CDA/impervious and infiltration scope)—not a single manual-wide inch value. Channel Protection extended detention release: 12 h to cold-water fisheries, 24 h to warm-water fisheries (CPv, not ED drain above pool). Bioretention filter bed 24–48 in required; 12 in allowed case-by-case. Swale max longitudinal slope 6% with check dams; wet swale pool often <6 in deep.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cambridge-ma", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cambridge-ma/", "data_url": "https://stormwateratlas.com/data/manuals/cambridge-ma.json", "document_metadata": { "jurisdiction_name": "City of Cambridge", "jurisdiction_level": "municipality", "state_code": "MA", "document_title": "Massachusetts Stormwater Management Handbook (city follows MassDEP Standards)", "version_or_edition": "Third Edition / 2023 draft handbook mirror", "adoption_or_effective_date": null, "last_revised_date": "2023-12", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Required runoff depth multiplied by total post-construction impervious site area (MassDEP Stormwater Management Standards / Handbook).", "peak_flow_calculation_method": [ "NRCS WinTR20", "WinTR55 Small Watershed Hydrology Method" ], "required_hydrologic_hydraulic_software": [ "WinTR-20", "WinTR-55" ], "approved_bmp_categories": [ "Non-Structural", "Structural Pretreatment", "Structural Treatment", "Structural Conveyance", "Structural Infiltration", "Structural Other" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Cambridge follows MassDEP Stormwater Handbook / Standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Performance Removal Curves and the MassDEP pollutant removal credits – i.e., the EPA-PRCs and MassDEP pollutant removal credits assume that the SCM has been designed with proper pretreatment in accordance with the Appendix A Structural SCM Specifications and the Massachusett", "page_or_section": "p. 30" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "calculated as the required runoff depth multiplied by the total post-construction impervious site area", "page_or_section": "MassDEP Handbook" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Required WQv is at least 1.0 inch times the total impervious area of the post-development site.", "page_or_section": "Table 2-4d / Chapter 2, page 2-33" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Media Filters must be sized to treat the water quality volume (1.0 inch)", "page_or_section": "Appendix A Media Filters, page A-102 area (~341)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "conduct drawdown analysis to ensure the design volume from impervious area will infiltrate over 3-days based on Step 3 \"Drawdown within 72 Hours\".", "page_or_section": "Chapter 6, page 6-36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Computations must reflect drawdown within the 72-hour period for whatever volume is directed to the recharge practice.", "page_or_section": "Chapter 6 Step 3, page 6-36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "It must be designed to fully dewater within 72-hours of a storm.", "page_or_section": "Appendix A Sediment Forebay, page A-58 (~297)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance from bottom of SCM to SHGW 2-ft", "page_or_section": "Chapter 2 Table setbacks, page 2-55 (~69)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Grass channels and dry water quality swales must be at least 2 feet above seasonal high groundwater.", "page_or_section": "Table 2-4d Cold-Water Fisheries, page 2-33 (~47)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The depth of the soil media must be between 2 to 4 feet.", "page_or_section": "Appendix A Bioretention, page A-72 (~311)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum acceptable final soil infiltration rate is 0.01 inches per hour.", "page_or_section": "Appendix A Infiltration Basin, page A-142 (~381)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water levels in the extended detention wetlands may increase by as much as three feet after a storm, and return gradually to normal within 24 hours of the rain event.", "page_or_section": "Appendix A Extended Detention Wetlands, page A-86 (~325)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via MassDEP handbook.", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.ashlandmass.com/DocumentCenter/View/13272/MassDEP-Handbook_DRAFT-6_2023-12-14_withAppendices-2", "landing_page_url": "https://www.mass.gov/guides/massachusetts-stormwater-handbook-and-stormwater-standards", "retrieved_at": "2026-08-10T09:54:53.530Z", "original_filename": "cambridge-ma.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T07:45:07.810Z", "enrich_model": "composer-2.5:run-6294f35c-d054-48c3-a4da-a5a601c1e8f1", "enrich_notes": "Cambridge follows MassDEP Massachusetts Stormwater Handbook. WQv is 1.0 inch × post-development impervious area. Infiltration and many SCM bottoms require 2 ft (24 in) separation from seasonal high groundwater (Table 2.5 / Appendix A setbacks). Recharge and infiltration drawdown is evaluated for full design volume within 72 hours. Bioretention filter media depth is 2–4 ft (24–48 in), with 30 in minimum where nitrogen TMDL anoxic media is required. Minimum acceptable soil infiltration rate for infiltration basins is 0.01 in/hr. Extended detention wetlands may rise up to ~3 ft after storms and return toward normal within 24 hours. Grass channels and dry water quality swales must be at least 2 ft above seasonal high groundwater near cold-water fisheries context.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cape-coral-fl", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cape-coral-fl/", "data_url": "https://stormwateratlas.com/data/manuals/cape-coral-fl.json", "document_metadata": { "jurisdiction_name": "City of Cape Coral", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Utility Standards — Design Procedures Manual (Volume 1 of 4)", "version_or_edition": "Adopted August 17, 2022", "adoption_or_effective_date": "2022-08-17", "last_revised_date": "2022-08-17", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Section 9 Storm Water Systems covers storm drain size/slope/depth, catch basins, and outfalls for utility infrastructure. Broader drainage design standards historically in Engineering Design Standards Section L (PDF currently 404); this utilities manual is conveyance-focused rather than full post-construction WQv criteria.", "peak_flow_calculation_method": [ "Storm drain sizing criteria (Section 9.1–9.3)", "Catch basin type and placement standards", "Outfall design requirements" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Storm drains / storm sewers", "Catch basins / inlets", "Outfalls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF CAPE CORAL", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CITY OF CAPE CORAL", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Cape Coral, FL", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "UTILITY STANDARDS VOLUME 1 OF 4: DESIGN PROCEDURES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "ADOPTED AUGUST 17, 2022", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "AUGUST 17, 2022", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "AUGUST 17, 2022", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Utility Standards / Engineering Design Standards referenced", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "SECTION 9 - STORM WATER SYSTEMS", "page_or_section": "Section 9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "9.1 STORM DRAIN SIZE / 9.2 STORM DRAIN SLOPE", "page_or_section": "Section 9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "CATCH BASINS / OUTFALLS", "page_or_section": "9.4–9.6" }, { "field": "practice_mentions.swale", "excerpt": "If the mains are placed beneath a swale, the depth of cover may be reduced to 30\" below the finished grade of the swale.", "page_or_section": "Section 2.1 GENERAL, page 11" }, { "field": "practice_mentions.swale", "excerpt": "If inlet is located at the bottom of the swale the two front bleed downs will be filled with grout. If the inlet is located in the bank of the swale, the 2 side bleed downs will be filled with grout.", "page_or_section": "Section 9.4 CATCH BASINS, page 59" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Utilities conveyance standards only; full Engineering Design Standards Section L PDF was 404 — replace when available.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.capecoral.gov/Documents/Departments/Utilities/Engineering%20Design%20Standards%20and%20Standard%20Detail%20Drawings/Utilities%20-%20Design%20Procedures%20Manual.pdf", "landing_page_url": "https://www.capecoral.gov/", "retrieved_at": "2026-08-10T08:56:34.266Z", "original_filename": "cape-coral-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T07:45:33.370Z", "enrich_model": "composer-2.5:run-8540d1b3-5fb2-46b0-b750-fc9ee83085fa", "enrich_notes": "Corpus is City of Cape Coral Utilities Design Procedures Manual (Volume 1): potable, irrigation, wastewater, force main, and Section 9 storm water systems for utility storm drain replacement/conveyance. Section 9 gives storm drain upsizing rules, preferred pipe slope 0.25% and minimum 0.10%, minimum cover 2.2 ft below edge of pavement, catch basin grate/bleeder elevations, and outfall 2-foot sump; no post-construction WQv depth, infiltration SCM sizing, drawdown, or seasonal high water table separation criteria. Swale references are for utility pipe cover (30 in below finished swale grade) and catch basin placement at swale bottom/bank, not vegetated swale BMP design dimensions.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "casper-wy", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/casper-wy/", "data_url": "https://stormwateratlas.com/data/manuals/casper-wy.json", "document_metadata": { "jurisdiction_name": "City of Casper", "jurisdiction_level": "municipality", "state_code": "WY", "document_title": "WYDOT Pollution Controls and BMPs for Storm Water During Construction — Field Guide (partial)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grading / perimeter sediment controls", "Vehicle tracking control", "Reclamation / mulching", "Spill prevention / waste management" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "disturb an acre or more to obtain coverage under the general construction storm water permit and to develop a plan to ensure that storm water runoff from the project is clean enough to discharge to surface waters without causing or contributing to water quality concerns. In", "page_or_section": "p. 2" }, { "field": "practice_mentions.swale", "excerpt": "Ditch Checks are designed to provide erosion control within man-made storm water conveyances such as ditches, channels, and swales.", "page_or_section": "DITCH CHECKS, page 17" }, { "field": "practice_mentions.swale", "excerpt": "Erosion Control Blankets Installed Running Along the Direction Of the Flow In This Swale.", "page_or_section": "EROSION CONTROL BLANKETS (continued), page 43" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Construction ESC field guide — not a full municipal post-construction design manual.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.dot.state.wy.us/files/live/sites/wydot/files/shared/Construction/WYDOT%20Storm%20Water%20Field%20Guide%204-6-11.pdf", "landing_page_url": "https://www.dot.state.wy.us/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "casper-wy.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T07:47:06.420Z", "enrich_model": "composer-2.5:run-776882dd-33af-442f-b591-6d1d6f0783b3", "enrich_notes": "Source is WYDOT Pollution Controls and BMPs for Storm Water During Construction (field guide), focused on temporary erosion/sediment control, vehicle tracking, reclamation, and spill/waste handling—not post-construction SCM sizing. Swales appear only as conveyances for ditch checks and erosion blankets; no design depths, drawdown times, WQV, infiltration rates, or other numeric stormwater facility parameters are stated.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cedar-rapids-ia", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cedar-rapids-ia/", "data_url": "https://stormwateratlas.com/data/manuals/cedar-rapids-ia.json", "document_metadata": { "jurisdiction_name": "City of Cedar Rapids", "jurisdiction_level": "municipality", "state_code": "IA", "document_title": "SUDAS Design Manual — Chapter 2 Stormwater (city adopts SUDAS + ISWMM)", "version_or_edition": "Chapter 02 (SUDAS Design Manual)", "adoption_or_effective_date": "2019-01-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Cedar Rapids adopted SUDAS effective Jan 1, 2019 (with city General Supplements). Ordinance Ch. 72 references Iowa Stormwater Management Manual (ISWMM) Design Standards for Stormwater Management Plans. SUDAS Ch. 2 defines Water Quality Volume (WQv) and Recharge Volume (Rev) and covers conveyance/detention (2G); ISWMM guides post-construction practice sizing.", "peak_flow_calculation_method": [ "Minor design storm (generally 2- to 10-year) for conveyance", "Major design storm (typically 100-year) for flood routing", "Detention basin design methods (Section 2G)", "ISWMM criteria for post-construction practices" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention practices", "Storm sewer / intake conveyance", "Water quality / recharge volume practices (ISWMM)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Cedar Rapids adopted SUDAS effective January 1, 2019", "page_or_section": "City SUDAS page" }, { "field": "document_metadata.document_title", "excerpt": "--- page 1 --- TOC Design Manual Chapter 2 - Stormwater Table of Contents Table of Contents i Revised: 2021 Edition Chapter 2 - Stormwater 2A General Information 2A-1--------------------------------General Information A. Concept…………………………………………………………………………... 1 B. Informin", "page_or_section": "p. 1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume, WQv / Design Standards include ISWMM", "page_or_section": "SUDAS Ch.2 / Municode Ch.72" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For Iowa, this equates to providing water quality treatment for the runoff resulting from a rainfall depth of 1.25 inches or less.", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 (page 9)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Channel Protection Storage Volume, Cpv — Provide 24 hours of extended detention of the runoff from the 1 year 24 hour duration storm event", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 (page 9)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1 year 24 hour duration storm event to reduce bank-full flows", "page_or_section": "2A-1 D. Unified Sizing Criteria (page 9)" }, { "field": "practice_mentions.swale", "excerpt": "Open Channel Flow - Swales and Ditches: Describe swale and ditch design.", "page_or_section": "2A-4 Project Drainage Report, 4.d (page 22)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Same SUDAS Ch.2 PDF as Des Moines coverage pattern; city supplements and ISWMM also apply. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.iowasudas.org/wp-content/uploads/sites/15/2020/03/Chapter_02.pdf", "landing_page_url": "https://cedar-rapids.org/local_government/departments_g_-_v/public_works/sudas_statewide_urban_design_and_specifications.php", "retrieved_at": "2026-08-10T09:39:14.794Z", "original_filename": "cedar-rapids-ia.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T07:47:29.515Z", "enrich_model": "composer-2.5:run-277c9162-564d-4ca8-86d6-e612d2585c73", "enrich_notes": "SUDAS Ch. 2 defines unified sizing: WQv treats runoff from storms up to 1.25 in rainfall (Iowa); stormwater quality BMP sizing is deferred to Iowa Stormwater Management Manual (ISWMM). Channel Protection Volume (Cpv) requires 24-hour extended detention of 1-year, 24-hour storm runoff. Excerpts cover conveyance, detention basin release rates, and swale/ditch reporting—not ISWMM practice dimensions.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "chandler-az", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/chandler-az/", "data_url": "https://stormwateratlas.com/data/manuals/chandler-az.json", "document_metadata": { "jurisdiction_name": "City of Chandler", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Engineering Design Standards Manual", "version_or_edition": "January 2025", "adoption_or_effective_date": "2025-01-27", "last_revised_date": "2025-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Chapter 3 Storm Drainage System Design includes stormwater quality and runoff control. On-site retention basins and drywells are primary local practices (Maricopa County MAG standards referenced).", "peak_flow_calculation_method": [ "Storm Drainage System Design (Chapter 3)", "Runoff control criteria", "On-site retention basin design", "Drywell registration/design per ADEQ/EPA updates" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention basins", "Drywells", "Storm drainage systems", "Landscaped medians/retention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Chandler", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Chandler", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "drawing meets the requirements of Arizona Department of Environmental Quality’s rules R18-4-215, R18-9-602, and R18-9-704.” with the engineer’s signature and professional engineering license number under this statement. Each As-Built sheet must be sealed as “As-Built” by an", "page_or_section": "p. 59" }, { "field": "document_metadata.document_title", "excerpt": "Engineering Design Standards Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "January 2025", "page_or_section": "Change Summary" }, { "field": "document_metadata.last_revised_date", "excerpt": "January 2025", "page_or_section": "Change Summary" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "MAG Uniform Standard Specifications", "page_or_section": "Purpose" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater Quality", "page_or_section": "Chapter 3 TOC" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Storm Drainage System Design / Runoff Control", "page_or_section": "Chapter 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Basins / Drywells", "page_or_section": "Standards sections" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Each basin must be demonstrated to be dry within 36 hours, by utilizing one-half of the tested basin infiltration rate and drywells.", "page_or_section": "Chapter 3 – Storm Drainage System Design, §3.6.10.4 Disposal of Stormwater / Basin Infiltration (manual p. 76)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "The infiltration rate of the bottom surface of proposed retention basins must be characterized by double-ring infiltrometer tests", "page_or_section": "Chapter 3, §3.6.10.4 Basin Infiltration (manual p. 76)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Chandler EDS Jan 2025; confirm numeric retention depth from Chapter 3 tables. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.chandleraz.gov/sites/default/files/departments/development-services/City-of-Chandler-Engineering-Design-Standards-Manual.pdf", "landing_page_url": "https://www.chandleraz.gov/", "retrieved_at": "2026-08-10T08:18:32.603Z", "original_filename": "chandler-az.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 36, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin" ], "enriched_at": "2026-08-13T07:47:54.719Z", "enrich_model": "composer-2.5:run-a75cf4f6-6ece-4027-9426-63905280f86b", "enrich_notes": "Provided corpus is mostly Chapters 1–2 (water/wastewater/reclaimed) plus a short Chapter 3 §3.6.10.4 excerpt on retention-basin infiltration testing, rock pits, and drywells. Atlas notes WQv and retention depth in Chapter 3 tables are not included in these excerpts; DDM Volume II Hydraulics and MAG are referenced for infiltration testing.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "charleston-sc", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/charleston-sc/", "data_url": "https://stormwateratlas.com/data/manuals/charleston-sc.json", "document_metadata": { "jurisdiction_name": "City of Charleston", "jurisdiction_level": "municipality", "state_code": "SC", "document_title": "Stormwater Design Standards Manual", "version_or_edition": "2026 SWDSM (COC_SWDSM_Final)", "adoption_or_effective_date": null, "last_revised_date": "2026-01-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Post-construction Chapter 6 addresses permanent BMPs and Water Quality Volume (WQV). Manual integrates drainage design, stormwater quantity, and water quality for public infrastructure, development, and redevelopment; includes conveyance design criteria and special protection area standards.", "peak_flow_calculation_method": [ "Stormwater quantity / conveyance design criteria", "Post-construction BMP / WQV requirements", "Roadway drainage design criteria", "Pre-construction through post-construction review process" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Post-construction stormwater BMPs", "Water quality treatment practices", "Conveyance / roadway drainage facilities", "Erosion and sediment control BMPs (construction)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF CHARLESTON DEPARTMENT OF STORMWATER MANAGEMENT", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CITY OF CHARLESTON", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "SOUTH CAROLINA", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER DESIGN STANDARDS MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "2026 Stormwater Design Standards Manual", "page_or_section": "City webpage / filename" }, { "field": "document_metadata.last_revised_date", "excerpt": "SWAT Soil and Water Assessment Tool SWDSM Stormwater Design Standards Manual SWMM Stormwater Management Model SWMP Stormwater Management Plan or Stormwater Management Program SWPPP Stormwater Pollution Prevention Plan TMDL Total Maximum Daily Load TRC Technical Review Committ", "page_or_section": "pp. 16–18" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City of Charleston Stormwater Design Standards Manual", "page_or_section": "Purpose" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV Water Quality Volume / Chapter 6 Post-Construction", "page_or_section": "TOC / Chapter 6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "conveyance design criteria and design criteria for roadway drainage", "page_or_section": "Design criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "permanent construction stormwater management practices / BMPs", "page_or_section": "Introduction" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The infiltration device shall be designed to completely drain of water within 72 hours.", "page_or_section": "Section 3.10.4 / page 97" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Permeable pavement systems shall be designed to completely drain within 72 hours.", "page_or_section": "Section 3.12.2 / page 101" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration practice shall be at least 0.5 feet above the seasonal high water table", "page_or_section": "Section 3.10.4 / page 97" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a standard separation distance of at least 0.5 feet between the seasonally high groundwater table ... and the bottom invert of the filter strip", "page_or_section": "Section 3.12.13.1 / page 106" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Tier Rainfall Depth (inches) I – Green Infrastructure 1.0 ... III – Detention Practices 2.8", "page_or_section": "Table 3, TPD 8 / page 240" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the stormwater runoff for a slow release over at least 24-hours and no more than 72 hours", "page_or_section": "Section 3.12.12 / page 105" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The maximum infiltration rate that can be used for design purposes is 3.0 inches per hour.", "page_or_section": "TPD 9 / page 244" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Pre-fabricated or proprietary treatment devices are approved on a case-by-case basis if adequate removal efficiency can be demonstrated. Provide pollutant removal efficiency data from a third-party testing company.", "page_or_section": "Appendix E checklist / page 187" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "2026 SWDSM; confirm council adoption date; numeric WQV depths in later chapters.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.charleston-sc.gov/DocumentCenter/View/41286/COC_SWDSM_Final---2026", "landing_page_url": "https://charleston-sc.gov/351/Stormwater-Design-Standards-Manual", "retrieved_at": "2026-08-10T09:06:14.926Z", "original_filename": "charleston-sc.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:48:35.642Z", "enrich_model": "composer-2.5:run-9983e43b-0567-4c6e-9604-9510185ce267", "enrich_notes": "Water quality sizing uses a tiered 24-hour rainfall depth (Table 3): Tier I GI 1.0 in, Tier I near shellfish beds 1.5 in, Tier II GI with underdrain 2.0 in, Tier III detention 2.8 in, Tier IV pass-through sized to peak flow from 2.8 in. Appendix E checklist cites wet ponds for first 0.5 in of runoff and dry ponds for first 1.0 in, with minimum 24-hour release. Many BMP detail dimensions defer to Low Impact Development in Coastal South Carolina: A Planning and Design Guide (Ellis et al. 2014). Infiltration soils require field rate ≥0.5 in/hr; design rate uses minimum FOS 2 (half field measured); maximum design infiltration rate is 3.0 in/hr unless design exception. Extended detention and wetland release windows are 24–72 hours. Dry/grass swale channels described as typically 4–18 inches deep (depth, not bottom width).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "charleston-wv", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/charleston-wv/", "data_url": "https://stormwateratlas.com/data/manuals/charleston-wv.json", "document_metadata": { "jurisdiction_name": "City of Charleston", "jurisdiction_level": "municipality", "state_code": "WV", "document_title": "Stormwater Management Guidance Manual", "version_or_edition": "Version 1.0", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Capture and infiltrate the first one (1) inch of rainfall on site (average 24-hour storm preceded by 48 hours of no measurable precipitation). Extended filtration practices designed to manage one inch of rainfall may discharge through an underdrain. Used as the City standard for water quality / post-construction runoff control (Ch.6).", "peak_flow_calculation_method": [ "Engineering calculations (Ch.4)", "Detention basins (Ch.6.13)", "LID / runoff reduction practices" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration practices", "Bioretention / planters", "Permeable pavement", "Impervious surface disconnection", "Detention basins", "Other Ch.6 post-construction measures" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Guidance Manual Version 1.0 City of Charleston, WV", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "infiltrating the first one (1) inch of rainfall on the site", "page_or_section": "Post-construction / permitting" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "manage on-site the first 1-inch of rainfall from an average 24-hour storm preceded by 48 hours of no measurable precipitation", "page_or_section": "Ch.6 Post Construction" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Volume Control (3) (i.e. Infiltration) 1 inch", "page_or_section": "Table 2-4, page 39" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "requires the first one (1) inch of rainfall to be managed", "page_or_section": "Section 6.6.7, page 152" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum drain time for the entire storage volume (surface, planting soil, and gravel if used) is 48 hours.", "page_or_section": "Section 6.6.6, Table 6-6.1 procedure step 3, page 151" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum drain down time for the entire storage volume is 48 hours.", "page_or_section": "Section 6.7.6, page 161" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Minimum depth of 24 in.; 36 in. recommended; (18 in. if an infiltration sump is used )", "page_or_section": "Table 6-6.3, page 153" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Minimum Filter Media Depth • 18 inches", "page_or_section": "Table 6-12.3, page 202" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Typical Ponding Depth* 6 – 12 inches ... *Note pond depth may not exceed 18 inches", "page_or_section": "Table 6-6.1, page 151" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Use the Infiltration Design for tested infiltration rates > 0.5 in. per hr.", "page_or_section": "Table 6-6.2, page 152" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Minimum Soil Infiltration Rate • 0.5 in./hr. (or use underdrain)", "page_or_section": "Table 6-12.3, page 202" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "outlets have been designed to detain stormwater runoff for some minimum time (e.g., 48 hours)", "page_or_section": "Section 6.13.1, page 205" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Longitudinal slope is no greater than 4% (check dams may be used to reduce the effective slope)", "page_or_section": "Section 6.4.8 Minimum Swale Criteria, page 136" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "maximum slope of four (4) percent", "page_or_section": "Section 6.4.6 step 2, page 134" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Extensive green roofs that have a growing media at least four (4) inches thick", "page_or_section": "Section 6.9.6 step 3, page 178" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Soil media ≥ 4”", "page_or_section": "Table 6-9.1, page 178" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width 2-8 feet", "page_or_section": "Table 6-4.1, page 134" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "http://charlestonstormwater.org/wp-content/uploads/2025/03/Charleston-Stormwater-Management-Guidance-Manual-website.pdf", "landing_page_url": "http://charlestonstormwater.org/sample-page/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "charleston-wv.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": 4, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:48:59.778Z", "enrich_model": "composer-2.5:run-d0dbf0d2-cc46-4f55-b285-46d677fe03b1", "enrich_notes": "WQv is 1 inch volume control (Table 2-4; Ch. 6). Bioretention filter media minimum 24 in. in Table 6-6.3 (18 in. only with infiltration sump); ponding typical 6–12 in., max 18 in. Infiltration-design threshold 0.5 in/hr (0.25 in/hr cited for infiltration sump at underdrain invert). Swale bottom width given as 2–8 ft range, not a single design width. Permeable pavement reservoir depth is site-variable (40% porosity for No. 57 stone); max drain 48 hr. Detention basins defer to external manuals; example minimum detain time 48 hr.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "charlottesville-va", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/charlottesville-va/", "data_url": "https://stormwateratlas.com/data/manuals/charlottesville-va.json", "document_metadata": { "jurisdiction_name": "City of Charlottesville", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Standards and Design Manual — Chapter 5 Stormwater Management", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "City Code Ch.10 VSMP: water quality per latest Virginia Stormwater BMP Clearinghouse Standards and Specifications and DEQ Stormwater Management Handbook (including drafts). Use DEQ Runoff Reduction Method spreadsheets for pollutant removal. Prefer on-site treatment; nutrient credits last resort for public projects. Flood protection: Part IIB / current VSMP; for existing man-made conveyance, contain post-development 10% AEP (10-year) 24-hour HGL within pipe/junctions. Check storm: 1% AEP (100-year) with emergency overflow. NOAA Atlas 14 rainfall; VDOT Drainage Manual for conveyance.", "peak_flow_calculation_method": [ "NOAA Atlas 14 / SCS 24-hour methods", "Rational Method", "VDOT Drainage Manual conveyance criteria", "DEQ Runoff Reduction Method (quality)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Virginia BMP Clearinghouse practices", "Bioretention / GSI (preferred)", "Stormwater tree planters / curb extensions", "Underground detention (with CCTV access)", "Other Clearinghouse-listed BMPs" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "CHARLOTTESVILLE STANDARDS & DESIGN MANUAL Chapter 5: Stormwater Management", "page_or_section": "Ch.5 headers" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "latest Virginia Stormwater BMP Clearinghouse Standards and Specifications and DEQ Stormwater Management Handbook", "page_or_section": "§5.4.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "post-development 10% AEP 24-hour storm event ... 1% AEP storm event shall be utilized as a check storm", "page_or_section": "§5.3.1.1–5.3.1.2" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The standard minimum filter bed depth ranges from 24 to 36 inches (uncompacted) for Level 1 and Level 2 designs, respectively (18 to 24 inches for rain gardens or micro-bioretention).", "page_or_section": "Chapter 10: Trees and Landscape pg. 190 (10.2.2.1 Bioretention Planting Soils)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "A maximum 8% longitudinal slope shall be applied to the system unless otherwise approved. Subgrade slopes greater than 3% should include check dams or baffles.", "page_or_section": "Chapter 5: Stormwater Management pg. 111 (5.5.1 Permeable interlocking concrete pavers)" }, { "field": "practice_mentions.bioretention", "excerpt": "If underdrains are proposed, the maximum stone depth permitted to be used in the quality calculations is 18 inches.", "page_or_section": "Chapter 5: Stormwater Management pg. 110 (Green Stormwater Infrastructure — Bioretention)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.charlottesville.gov/DocumentCenter/View/10298", "landing_page_url": "https://va-charlottesville.civicplus.com/491/Stormwater", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "charlottesville-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:50:02.040Z", "enrich_model": "composer-2.5:run-558cd6e1-c736-41b0-b5bc-2093f34c74f9", "enrich_notes": "City defers water-quality sizing to Virginia BMP Clearinghouse and DEQ Handbook; local text adds GSI preferences, underdrain spacing (10 ft), max 18 in stone counted toward quality for underdrained planters/bioretention, permeable pavers max 8% longitudinal slope and subgrade >3% needs check dams/baffles, and bioretention filter bed depth tiers (18–24 in rain garden/micro; 24–36 in Level 1/2).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "chattanooga-tn", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/chattanooga-tn/", "data_url": "https://stormwateratlas.com/data/manuals/chattanooga-tn.json", "document_metadata": { "jurisdiction_name": "City of Chattanooga", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Rainwater Management Guide (RMG)", "version_or_edition": "December 1, 2014 edition with Addenda (Addendum 1 11/29/2017; Addendum 2 08/30/2019)", "adoption_or_effective_date": "2014-12-01", "last_revised_date": "2019-11-15", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Stay-On Volume (SOV) runoff reduction: entire City uses 1.0 inch of rainfall for SOV (required for ≥1 acre disturbance; may be based on impervious area). Performance standards also address water quality treatment and peak rate control; LID/green infrastructure preferred. Infeasibility pathways documented in RMG/addenda.", "peak_flow_calculation_method": [ "Stay-On Volume (SOV) calculation", "Stormwater management performance standards (Chapter 3)", "BMP Excel Workbook / calculation methodologies (Chapter 7)", "Peak rate control standards" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Runoff reduction / Stay-On Volume practices", "Green infrastructure / LID BMPs", "Manufactured treatment devices (per Addendum 2)", "Structural stormwater control measures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Chattanooga Rainwater Management Guide", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Chattanooga", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Rainwater Management Guide", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Addendum 1 – 11/29/2017 / Addendum 2 – 08/30/2019", "page_or_section": "TOC / Addenda" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "December 1, 2014 edition", "page_or_section": "Addendum 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "Addendum 2, Revision 1 – 11/15/2019", "page_or_section": "TOC" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City RMG / NPDES MS4 Permit technical guidance", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "entire City of Chattanooga will use 1.0\" of rainfall for SOV", "page_or_section": "Addendum 1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Stormwater Management Performance Standards", "page_or_section": "Chapter 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stay-On Volume (SOV) measures / stormwater management practices", "page_or_section": "Addendum 1 / Chapter 5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If standing water is observed or measured after 72 hours, this will be considered a clear sign that the SCM is not functioning properly", "page_or_section": "Chapter 8, page 7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All underdrain systems must discharge the water quality volume (WQv) between 48 and 72 hours.", "page_or_section": "RMG Page 5.3.5-14" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "High permanent groundwater table (< 2 feet to water table from bottom of proposed SCM)", "page_or_section": "Chapter 8 – Site Infeasibilities, page 5" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the depth from the base of a proposed infiltration SOV management strategy to seasonal high groundwater or other limiting layer is less than 2 feet", "page_or_section": "Chapter 3, page 44" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "the green roof must be designed with a minimum media depth of 2½ inches.", "page_or_section": "RMG Page 5.3.8-8" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "2 to 6 inches of engineered growing media with high mineral content", "page_or_section": "RMG Page 5.3.8-4" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "For green roofs situated atop roofs with slopes greater than 1.5 percent, battens should be incorporated", "page_or_section": "RMG Page 5.3.8-8" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "proprietary, man-made devices meeting NJCAT verification (www.njcat.org) and using 3.1\" storm.", "page_or_section": "Chapter 8, page 5" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "proprietary, man-made devices must have NJCAT verification (www.njcat.org) and use 3.1\" of rainfall for design purposes.", "page_or_section": "Addendum Chapter 5 comments, page 8" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Full RMG binder with addenda; text truncated at ~1M chars. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://chattanooga.gov/sites/default/files/2024-06/Chattanooga-RMG-Binder.pdf", "landing_page_url": "https://chattanooga.gov/stay-informed/environmental-initiatives/rainsmart-water-conservation-programs/resource-rain", "retrieved_at": "2026-08-10T08:56:34.266Z", "original_filename": "chattanooga-tn.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 2.5, "green_roof_slope_percent": 1.5, "mtd_verification_program": "NJCAT", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:50:40.813Z", "enrich_model": "composer-2.5:run-f5bc763f-b4a2-4b53-a988-73cfcd15aa79", "enrich_notes": "Stay-On Volume (SOV) is the city's runoff-reduction framework; atlas context cites 1.0 in. citywide but that value does not appear in the supplied excerpts. Infeasibility uses infiltration <0.5 in/hr and high groundwater <2 ft below SCM bottom. Alternate infeasibility treatment: modified GI at 2.1 in. storm, extended detention at 3.1 in., or NJCAT devices at 3.1 in. with ≥80% TSS. WQv underdrain discharge window 48–72 hr (Ch. 5 swale/bioretention underdrain text). Green roof growing media stated as 2–6 in.; SOV credit requires minimum 2.5 in. media. Infiltration berm ponding depth limited to 6 in. or less (not mapped to bioretention ponding field).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent" ] } }, { "slug": "chesapeake-va", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/chesapeake-va/", "data_url": "https://stormwateratlas.com/data/manuals/chesapeake-va.json", "document_metadata": { "jurisdiction_name": "City of Chesapeake", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Stormwater Management and Drainage Design", "version_or_edition": "Revised December 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Virginia Runoff Reduction Method (VRRM) with DEQ compliance spreadsheets: prevent a net increase in nonpoint source pollution for new development (post-development load shall not exceed predevelopment based on average land cover conditions); for redevelopment, achieve a 10% reduction when land disturbance is less than one acre and a 20% reduction when one acre or greater (Chesapeake Bay Preservation Area Designation and Management Regulations). Non-proprietary BMP pollutant removal efficiencies in Table 4.1 are based upon 1 inch of rainfall.", "peak_flow_calculation_method": [ "Rational method (storm drainage HGL; <200 acres = 10-year, >200 acres = 50-year)", "NRCS / SCS Type II 24-hour hydrographic methods (basins >200 acres or detention design)", "NRCS runoff curve number / volumetric runoff coefficients" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-GeoHMS", "TR-55", "TR-20", "Pond Pack", "WMS / Watershed Modeling", "HEC-RAS", "EPA SWMM", "FHWA HY-8", "CulvertMaster", "FlowMaster", "Virginia Runoff Reduction Method (VRRM) Compliance Spreadsheet", "HSPF" ], "approved_bmp_categories": [ "Rooftop Disconnection", "Sheetflow to Vegetated Filter or Conserved Open Space", "Grass Channel", "Soil Amendments", "Vegetated Roof", "Rainwater Harvesting", "Permeable Pavement", "Infiltration", "Bioretention / Urban Bioretention", "Dry Swale", "Wet Swale", "Filtering Practice", "Constructed Wetland", "Wet Pond", "Extended Detention Pond", "Dry Detention (Virginia Stormwater Management BMP Clearinghouse)", "Wet Detention (Virginia Stormwater Management BMP Clearinghouse)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "the City's Stormwater Management Ordinance, Chapter 26 - Article X of the City of Chesapeake Code", "page_or_section": "Section 5.4 B. Water Quality, Page 5-16" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Stormwater, for both water quantity and quality, shall be designed in general by the criteria established herein, the City's Master Drainage Plan", "page_or_section": "Section 5.0 GENERAL" }, { "field": "document_metadata.state_code", "excerpt": "the Virginia Department of Transportation Drainage Manual and the Virginia Stormwater Management Handbook", "page_or_section": "Section 5.0 GENERAL" }, { "field": "document_metadata.document_title", "excerpt": "CHAPTER 5 STORMWATER MANAGEMENT & DRAINAGE DESIGN", "page_or_section": "Page 5-1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised 12/16 STORMWATER MANAGEMENT & DRAINAGE DESIGN", "page_or_section": "Page headers" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised 12/16", "page_or_section": "Page headers" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Stormwater, for both water quantity and quality, shall be designed in general by the criteria established herein, the City's Master Drainage Plan, the Virginia Department of Transportation Drainage Manual and the Virginia Stormwater Management Handbook. When there is a conflict between the Virginia Department of Transportation Drainage Manual, the Hampton Roads Planning District Commission Regional Construction Standards and these criteria, these criteria shall govern.", "page_or_section": "Section 5.0 GENERAL A–B" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "24 Hour Rainfall Depths (NOAA's NWS)... 2-yr. 3.7\" 5-yr. 5.0\" 10-yr. 6.0\" 25-yr. 7.0\" 50-yr. 8.17\" 100 9.44\"", "page_or_section": "Section 5.2 HYDROLOGY B, Page 5-5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Storm drainage systems including Hydraulic Grade Line, etc. shall be designed using the rational method, for the recurrence frequency as follows: 0 < 200 Acres = 10-year (07/01) > 200 Acres = 50-year", "page_or_section": "Section 5.3 HYDRAULICS A.1, Page 5-7" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The SWMM models developed for these drainage studies are specific design scenarios based on 2-, 5-, 10-, 25-, 50-, and 100 year rainfall events", "page_or_section": "Section 5.3 HYDRAULICS A.2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "All public detention systems shall be designed to withstand a 100 year storm without failure of the control structure or property damage.", "page_or_section": "Detention criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Virginia's proposed Stormwater Management Program (VSMP) Permit Regulations (4 VAC 50-60 et seq.) include water quality and quantity requirements based, in part, on the \"Virginia Runoff Reduction Method\" (VRRM).", "page_or_section": "Section 5.4 B. Water Quality" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "prevent a net increase in nonpoint source pollution Citywide from new development (i.e. the post development nonpoint source pollution runoff load cannot exceed the predevelopment load based on average land cover conditions) and achieve either a 10% or 20% reduction in nonpoint source pollution for redevelopment... A 10% reduction is required is when land disturbance is limited to less than one acre and a 20% reduction is required when land disturbance is one acre or greater.", "page_or_section": "Section 5.4 C.1.b Design Criteria, Page 5-16" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Table 4.1. BMP Pollutant Removal Efficiencies (March 1, 2011)... Removal of TP by Runoff Reduction (RR, as %) (based upon 1 inch of rainfall)", "page_or_section": "Table 4.1, Pages 5-18–5-19" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Storm drainage systems including Hydraulic Grade Line, etc. shall be designed using the rational method, for the recurrence frequency as follows", "page_or_section": "Section 5.3 HYDRAULICS A.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Where the drainage basin exceeds 200 acres or when a detention design is involved, hydrographic or other approved methods are to be used for design purposes. Hydrographs shall be based on a Soil Conservation Service (SCS) Type II, 24-hour duration storm.", "page_or_section": "Section 5.2 HYDROLOGY B" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "drainage area maps including all offsite area, time of concentration and flow paths, imperviousness of the entire site and each watershed, NRCS runoff curve numbers or volumetric runoff coefficients, peak runoff rates, volumes and velocities", "page_or_section": "Section 5.0 GENERAL C" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "25-yr. 7.0” 50-yr. 8.17” 100 9.44” C. Acceptable methods for runoff analysis are tabulated below: Model Major Sys. Minor Sys. Hydrologic Hydraulic Water Quality Hydrology Software HEC-GeoHMS X X HEC-HMS X X TR-55 X TR-20 X Pond Pack X X X WMS X X Watershed Modeling X X Hydrauli", "page_or_section": "p. 5" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The storwmwater design is based off of DEQ's (Virginia Runoff Reduction Method\" (VRRM). The VRRM is accompanied by two compliance spreadsheets.", "page_or_section": "Section 5.4 Design Calculations 5.a, Page 5-19" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "and/or maintenance. 4. Acceptable BMP Facilities: Post construction BMPs can be either Non-Proprietary BMPs or Proprietary/Manufactured BMPs. DEQ is currently evaluating Proprietary/Manufactured BMP’s for recommended efficiencies; there are no approved Proprietary/Man", "page_or_section": "p. 18" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Dry Detention Requirements shall meet the requirements of the Virginia Stormwater Management BMP Clearinghouse... Wet Detention Requirements shall meet the requirements of the Virginia Stormwater Management BMP Clearinghouse", "page_or_section": "Detention requirements 19–20" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Removal of TP by Runoff Reduction (RR, as %) (based upon 1 inch of rainfall)", "page_or_section": "Table 4.1, page 5-18" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "detention facilities must be designed to return to a water surface elevation that will provide 90% of the design event storage capacity within 48 hours", "page_or_section": "5.4 STORMWATER MANAGEMENT, page 5-13" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "projected seasonal high water table will be a minimum of 12\" below proposed flow line", "page_or_section": "5.4 Dry Detention Requirements e., page 5-14" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum normal water depth for public facilities shall be 8 feet", "page_or_section": "5.4 Wet Detention Requirements b., page 5-15" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "provide 90% of the design event storage capacity within 48 hours of the beginning of a 24 hour SCS 10-year storm", "page_or_section": "5.4 STORMWATER MANAGEMENT item 3, page 5-13" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "minimum grade of .5%", "page_or_section": "5.3 C. Ditches, Channels, & Swales item 3, page 5-11" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "PFM Chapter 5 excerpt (Revised 12/16). City criteria govern over VDOT/HRPDC conflicts; also references Virginia Stormwater Management Handbook. Design-storm list from NOAA Atlas 14 depth table plus drainage/detention frequencies. Software list is the city's tabulated acceptable methods (not exclusive mandates); VRRM spreadsheets are required for nutrient compliance. adoption_or_effective_date not stated beyond 'Revised 12/16'.", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.cityofchesapeake.net/DocumentCenter/View/2455/Stormwater-Management-and-Drainage-Design-PDF", "landing_page_url": "https://www.cityofchesapeake.net/", "retrieved_at": "2026-08-08T10:27:34.715Z", "original_filename": "chesapeake-va.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 96, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:51:12.933Z", "enrich_model": "composer-2.5:run-22a68933-0fd9-4e7c-8d1a-ef5ae882555d", "enrich_notes": "Chapter 5 (Revised 12/16) defers BMP sizing to Virginia Stormwater Management BMP Clearinghouse and VRRM spreadsheets; city adds wet/dry detention geometry, 48-hour detention recovery, and coastal-plain wet-pond removal adjustments in Table 4.1 footnotes. No proprietary/manufactured BMPs approved at time of text. Grass-channel dry detention requires 12 in SHWT clearance below flow line.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cheyenne-wy", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cheyenne-wy/", "data_url": "https://stormwateratlas.com/data/manuals/cheyenne-wy.json", "document_metadata": { "jurisdiction_name": "City of Cheyenne", "jurisdiction_level": "municipality", "state_code": "WY", "document_title": "WYDOT Pollution Controls and BMPs for Storm Water During Construction — Field Guide (partial)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grading / perimeter sediment controls", "Vehicle tracking control", "Reclamation / mulching", "Spill prevention / waste management" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Cheyenne — partial coverage via WYDOT construction stormwater field guide", "page_or_section": "Coverage note" }, { "field": "practice_mentions.swale", "excerpt": "Ditch Checks are designed to provide erosion control within man-made storm water conveyances such as ditches, channels, and swales.", "page_or_section": "cheyenne-wy-c0025 | DITCH CHECKS | pages 17-19" }, { "field": "practice_mentions.swale", "excerpt": "Erosion Control Blankets Installed Running Along the Direction Of the Flow In This Swale.", "page_or_section": "cheyenne-wy-c0039 | RECLAMATION | pages 42-43" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Construction ESC field guide — not a full municipal post-construction design manual.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.dot.state.wy.us/files/live/sites/wydot/files/shared/Construction/WYDOT%20Storm%20Water%20Field%20Guide%204-6-11.pdf", "landing_page_url": "https://www.dot.state.wy.us/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "cheyenne-wy.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T07:51:31.900Z", "enrich_model": "composer-2.5:run-33565800-aa5c-4e75-8449-c01a2b4ca79a", "enrich_notes": "Source is WYDOT Pollution Controls and BMPs for Storm Water During Construction (field guide). Content covers erosion control, sediment control, vehicle tracking, reclamation/mulching, and materials/waste/spill BMPs during construction—not post-construction stormwater quality or quantity SCM sizing. No explicit numeric design parameters from the target schema appear in the provided excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "chicago-il", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/chicago-il/", "data_url": "https://stormwateratlas.com/data/manuals/chicago-il.json", "document_metadata": { "jurisdiction_name": "City of Chicago", "jurisdiction_level": "municipality", "state_code": "IL", "document_title": "Stormwater Management Ordinance Manual", "version_or_edition": "August 2024", "adoption_or_effective_date": "2024-08", "last_revised_date": "2024-08", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Capture one-half inch of runoff from all impervious surfaces, or achieve a fifteen-percent reduction in impervious surfaces from existing conditions for developments not discharging to Waters or MS4.", "peak_flow_calculation_method": [ "Rational Method", "Modified Rational Method", "Hydrograph Methods", "HEC-1", "HEC-HMS", "TR-20", "TR-55", "SWMM" ], "required_hydrologic_hydraulic_software": [ "Stormwater Spreadsheet Tool" ], "approved_bmp_categories": [ "Combined Sewers", "Ditches, Swales, and Natural Channels", "Storm Sewers", "Detention Basins", "Detention Vaults", "Oversized Pipes", "Parking Lot Detention", "Rooftop Detention", "Green Roofs", "Rooftop Runoff BMPs (Planter Boxes, Rain Barrels and Cisterns)", "Permeable Paving", "Natural Landscaping", "Vegetated Filter Strips", "Bioinfiltration Systems", "Drainage Swales", "Infiltration Vault" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Chicago", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Chicago", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Chicago, Illinois 60602", "page_or_section": "Page 3, Section 1.4" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Ordinance Manual", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Introduction This Stormwater Manual (Manual) was created for developers, engineers and architects preparing development plans in the City of Chicago. The goals of the Manual are to provide the technical tools and guidelines necessary to comply with the Stormwater Ordinance an", "page_or_section": "p. 7" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Velocities must be 1 ft/sec or less during the 2-year storm event... minor drainage systems for small storm events of up to the 5-year storm event... storage for a minimum 10-year event... 25-year storm analysis... 100-year storm event", "page_or_section": "Pages 7, 14, 24, 36, 39" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Capture one-half inch of runoff from all impervious surfaces in accordance with volume control BMPs; or (B) For Developments that do not directly discharge to Waters or to a municipal separate storm sewer system, achieve a fifteen-percent reduction in impervious surfaces from existing conditions.", "page_or_section": "Page 26, Section 3.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Modified Rational Method to calculate the maximum volume of stormwater... Rational Method... hydrograph methods with regional rainfall data... HEC-1 and HEC-HMS... TR-20... TR-55... SWMM", "page_or_section": "Pages 7, 15, 16, B-6, B-7" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The initial site plans, Stormwater Management Plan (SMP), Stormwater Spreadsheet Tool and all other supporting documentation must be submitted to DOB", "page_or_section": "Page 3, Section 1.4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "control and are discussed below. • Green Roofs • Rooftop Runoff BMPs (Planter Boxes, Rain Barrels and Cisterns) • Permeable Paving • Natural Landscaping • Vegetated Filter Strips • Bioinfiltration Systems • Drainage Swales • Infiltration Vault (also see Section 2.5.2)", "page_or_section": "p. 42" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "subsoil infiltration rates are 0.5 inches per hour or greater", "page_or_section": "3.2.1 Practicability of Infiltration BMPs, page 33" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The high groundwater table must be at least 2 feet below the bottom of all proposed infiltration BMP", "page_or_section": "3.2.1, page 33" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Dry bottom basins must be capable of draining within 72 hours of a storm event", "page_or_section": "Appendix A RATE CONTROL BMPS — Detention Basins, page 62" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Dry bottom basins must be capable of draining within 72 hours of a storm event", "page_or_section": "Ch III, 3.2 / Appendix A, page 62" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet detention basins without vegetation shall be at least 3 feet deep", "page_or_section": "Appendix A, page 63" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The growing medium soil must be a mix of 40% sand, 30% topsoil and 30% compost. The soil must be at least 2 feet deep", "page_or_section": "Appendix C Bioinfiltration Minimum Design Requirements, page 84" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The design of a bioinfiltration facility shall allow no more than 12 inches of depressional ponding in the vegetated area", "page_or_section": "Appendix C, page 84" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The underlying soil shall have a permeability of 0.5 in/hr or greater", "page_or_section": "Appendix C Bioinfiltration, page 84" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "The document clearly defines the City of Chicago's independent stormwater manual, its return periods (2, 5, 10, 25, 100 years), its volume control target (0.5 inches of runoff or 15% impervious reduction), and its calculation methods (Rational, Modified Rational, and hydrograph models). All requested fields were successfully extracted with exact text evidence. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.chicago.gov/content/dam/city/depts/water/general/Engineering/SewerConstStormReq/2024StormwaterManual.pdf", "landing_page_url": "https://www.chicago.gov/city/en/depts/water.html", "retrieved_at": "2026-08-07T21:21:20.846Z", "original_filename": "chicago-il.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:52:20.283Z", "enrich_model": "composer-2.5:run-cc99b248-b583-46de-a9bc-a38c59d6f518", "enrich_notes": "Volume control in excerpts emphasizes 15% impervious reduction and worksheet 1-inch storm volumes; no explicit half-inch WQv depth in corpus. SHWT separation is 2 ft (24 in) below BMP bottom, or 3.5 ft (42 in) for combined sewer / underdrains. Bioinfiltration drain within 5 days (120 hr); permeable aggregate underdrain systems within 48 hr. Green roof max slopes: extensive 25%, intensive 10%. Swale longitudinal slope range 0.5–2.5% stated as a range.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "chula-vista-ca", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/chula-vista-ca/", "data_url": "https://stormwateratlas.com/data/manuals/chula-vista-ca.json", "document_metadata": { "jurisdiction_name": "City of Chula Vista", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "City of San Diego Stormwater Standards (San Diego County MS4 regional reference)", "version_or_edition": "August 2024 Edition", "adoption_or_effective_date": "2024-08-15", "last_revised_date": "2024-08", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Design Capture Volume (DCV): retain onsite pollutants in runoff from the 24-hour, 85th percentile storm event. If full retention is not feasible, biofiltration for remaining volume (treat 1.5× DCV not retained, or flow-thru biofiltration holding ≥0.75× DCV not retained). Chula Vista participates in the San Diego County regional MS4 program; city portal often 403 — San Diego Stormwater Standards used as regional technical reference pending a durable Chula Vista-specific PDF.", "peak_flow_calculation_method": [ "Continuous simulation hydrologic modeling", "Approved Q2/Q10 regression equations", "Rational method (runoff to BMPs)" ], "required_hydrologic_hydraulic_software": [ "San Diego Hydrology Model (SDHM)", "EPA SWMM" ], "approved_bmp_categories": [ "Harvest and Use", "Infiltration / Bioretention / Permeable pavement", "Biofiltration", "Flow-thru treatment controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Chula Vista — San Diego County MS4; coverage via City of San Diego Stormwater Standards as regional reference", "page_or_section": "Coverage note" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth to seasonally high groundwater tables (normal high depth during the wet season) beneath the base of any infiltration BMP must be greater than 10 feet for full infiltration BMPs to be allowed.", "page_or_section": "Appendix C.2.2.2, page 272" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Basin length to width ratio is ≥ 2:1 (L:W).", "page_or_section": "Appendix E dry extended detention, page 439" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "An active General Use Level Designation for Basic Treatment, Phosphorus Treatment or Enhanced Treatment under the Washington State Technology Acceptance Protocol-Ecology program is the preferred method", "page_or_section": "Appendix B.6, page 257" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "maximum 36-hour drawdown time for the aggregate storage layer, with surface ponding no greater than a maximum 24-hour drawdown", "page_or_section": "Appendix E INF-2 bioretention, page 386" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Surface ponding drawdown time is between 24 and 96 hours.", "page_or_section": "Appendix E dry extended detention, page 439" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Regional placeholder — replace with Chula Vista / County BMP Design Manual when a durable public PDF is available.", "fields_not_found": [] }, "source": { "document_url": "https://www.sandiego.gov/sites/default/files/2024-08/sws_manual_august_2024_update.pdf", "landing_page_url": "https://www.chulavistaca.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "chula-vista-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "TAPE", "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:52:55.245Z", "enrich_model": "composer-2.5:run-d393e0b7-368c-47d2-bb5c-696112fb03fb", "enrich_notes": "Chula Vista proxy uses San Diego County Stormwater Standards (August 2024). Pollutant control sizing is DCV from 24-hour 85th percentile rainfall (Appendix B), not a fixed inch WQV depth in excerpts. Bioretention and permeable pavement cite max 36-hour aggregate drawdown (24-hour surface ponding for bioretention); dry extended detention surface ponding drawdown 24–96 hours. Full infiltration requires seasonally high groundwater more than 10 ft below BMP base (Appendix C.2.2.2). Proprietary BMPs prefer Washington State TAPE General Use Level Designation.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "cincinnati-oh", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cincinnati-oh/", "data_url": "https://stormwateratlas.com/data/manuals/cincinnati-oh.json", "document_metadata": { "jurisdiction_name": "City of Cincinnati", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Rainwater and Land Development — Ohio's Standards for Stormwater Management (city MS4)", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "WQv (ac-ft) = C × 0.75 × A / 12 (treat runoff from 0.75 inch of precipitation); Ohio EPA NPDES requires 20% additional WQv for sediment; extended detention drawdown 24–48 hours. Used where no durable city design-manual PDF was found (or prior extract was empty/scanned).", "peak_flow_calculation_method": [ "NRCS TR-55", "USGS empirical equations for small urban streams in Ohio", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water Quality Ponds", "Infiltration / Filtration practices", "LID / Conservation Development", "Wetland / Stream setbacks" ] }, "evidence": [], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide Ohio manual used as MS4 post-construction reference when city PDF unavailable/empty. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name", "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "cincinnati-oh.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "infiltration_basin", "wet_pond" ], "enriched_at": "2026-08-13T07:53:31.933Z", "enrich_model": "composer-2.5:run-7c517b5f-00dd-42b8-b52e-6fa300d8e3a9", "enrich_notes": "Corpus pages 1–136 contain no extractable text (empty OCR). Atlas notes Ohio WQv uses 0.75 in precipitation (C×0.75×A/12), 20% additional WQv for sediment per Ohio EPA NPDES, and extended-detention drawdown 24–48 hours; those values are not in the source excerpts and are not reported as numeric fields. Approved BMP categories: Water Quality Ponds, Infiltration/Filtration, LID/Conservation Development, Wetland/Stream setbacks.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "clarksville-tn", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/clarksville-tn/", "data_url": "https://stormwateratlas.com/data/manuals/clarksville-tn.json", "document_metadata": { "jurisdiction_name": "City of Clarksville", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Storm Water Management Manual", "version_or_edition": "June 2014 / October 2014 chapter updates (Archive ADID 1469)", "adoption_or_effective_date": "2000-08-01", "last_revised_date": "2014-10-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "WQv = (1.11\") (Rv) (A) / 12 with Rv = 0.05 + 0.009(I). Chapter 9 covers post-construction stormwater quality, runoff reduction credits, bioretention, water quality swales, and related BMPs. Water quality buffers in Chapters 5/10.", "peak_flow_calculation_method": [ "SCS / TR-20 / HEC-HMS procedures", "Mandatory storm water dry detention (Ch. 7)", "IDF / regression equations (Ch. 7 updates)" ], "required_hydrologic_hydraulic_software": [ "TR-20", "HEC-HMS", "HEC-1" ], "approved_bmp_categories": [ "Bioretention", "Water quality swales", "Dry detention", "Wet detention / retention", "Permeable pavement", "Catchbasin inserts", "Stormwater credits / runoff reduction" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Clarksville Storm Water Management Manual", "page_or_section": "Revision History" }, { "field": "document_metadata.version_or_edition", "excerpt": "June 2014 / October 2014 Updated Chapter 4... Chapter 9, Post Construction", "page_or_section": "Revision History" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "August, 2000 Manual adopted by reference by Ordinance 3-2000-01", "page_or_section": "Revision History" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv = (1.11”) (Rv) (A) ... Rv = 0.05 + (I) (0.009)", "page_or_section": "Ch. 9 example / WQv calc" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Q2-yr / Q10-yr preliminary hydrologic calculations; 25-year spillway example", "page_or_section": "Design examples" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "9.7 Bioretention; 9.10 Water Quality Swales; permeable pavement specification", "page_or_section": "Ch. 9 TOC" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city stormwater management manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv = (1.11\") (Rv) (A) / 12", "page_or_section": "Appendix J, page 129" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv = (1.11\") (0.62) (3.0ac)", "page_or_section": "Appendix J, page 129" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The planting soil bed must be at least 4 feet deep.", "page_or_section": "Chapter 9.7.2, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The maximum ponding depth in bioretention areas is 6 inches.", "page_or_section": "Chapter 9.7.2, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The soil must have an infiltration rate of at least 0.5 inches per hour", "page_or_section": "Chapter 9.7.2, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil infiltration rate of 0.5 in/hr or greater required", "page_or_section": "Chapter 9.9, page 332" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The outlet is sized to detain the water quality volume for 24 hours.", "page_or_section": "Chapter 9.5.1, page 299" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "water is detained above the permanent pool and released over 24 - 48 hours", "page_or_section": "Chapter 9.5.1, page 299" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Design the pond with a minimum length to width ratio of 3:1", "page_or_section": "Chapter 9.5.2, page 299" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "length to width ratio of 2:1", "page_or_section": "Chapter 9.7.2, page 320" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The layer must have a minimum depth of nine inches.", "page_or_section": "Chapter 9.13.3, page 358" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "drain the entire treatment volume in less than 24 hours", "page_or_section": "Appendix J, page 122" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum of 2 feet", "page_or_section": "Chapter 9.7.2, page 321 (bottom of bioretention to seasonally high water table)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "at least 4 feet between the bottom of the infiltration trench and the elevation of the seasonally high water table", "page_or_section": "Chapter 9.9.2, page 334" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom widths must be between 2-8 feet wide.", "page_or_section": "Chapter 9.10.2, page 341" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Archive ADID=1469 labeled Stormwater Manual 2021 on city page; extracted PDF revision history tops out at Oct 2014 chapter updates. Large truncated text — medium confidence.", "fields_not_found": [] }, "source": { "document_url": "https://www.clarksvilletn.gov/Archive.aspx?ADID=1469", "landing_page_url": "https://www.clarksvilletn.gov/198/Permits-Manuals-Stormwater-Educational-M", "retrieved_at": "2026-08-10T09:39:14.764Z", "original_filename": "clarksville-tn.pdf" }, "design_parameters": { "wqv_depth_inches": 1.11, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 48, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:54:14.600Z", "enrich_model": "composer-2.5:run-3fe3fe1b-b48f-43c9-92e3-d6409fedb44c", "enrich_notes": "WQv rainfall depth 1.11 in per WQv = (1.11)(Rv)(A)/12. Bioretention: 48 h filter drain time, k=0.5 ft/day; SHWT min 2 ft below facility bottom; L:W 2:1. Ponds: L:W 3:1, max pond depth 8 ft; wet ED release 24–48 h; micropool WQv detention 24 h; Appendix J pond drains treatment volume in <24 h. Infiltration trench: SHWT 4 ft min, dewater WQv in 24–48 h. Permeable pavement: reservoir min 9 in, typical 2–4 ft, drain in 48 h. Swales: bottom 2–8 ft, max ponding <48 h, dry swale SHWT >3 ft below bottom. Proprietary devices reference Metro Nashville list, not TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cleveland-oh", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cleveland-oh/", "data_url": "https://stormwateratlas.com/data/manuals/cleveland-oh.json", "document_metadata": { "jurisdiction_name": "City of Cleveland", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Rainwater and Land Development — Ohio's Standards for Stormwater Management (city MS4)", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "WQv (ac-ft) = C × 0.75 × A / 12 (treat runoff from 0.75 inch of precipitation); Ohio EPA NPDES requires 20% additional WQv for sediment; extended detention drawdown 24–48 hours. Used where no durable city design-manual PDF was found (or prior extract was empty/scanned).", "peak_flow_calculation_method": [ "NRCS TR-55", "USGS empirical equations for small urban streams in Ohio", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water Quality Ponds", "Infiltration / Filtration practices", "LID / Conservation Development", "Wetland / Stream setbacks" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Cleveland MS4 — Ohio Rainwater and Land Development standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "for construction activities. WQv (ac-ft) = C * 0.7\u0018 * A / \u00182 (Equation \u0018) Where: C = runoff coefficient A = area draining into the BMP in acres The runoff coefficient, C, is calculated using the following equation or alternatively values provided in the current Ohio EPA NP", "page_or_section": "p. 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv (ac-ft) = C * 0.75 * A / 12", "page_or_section": "CHAPTER 2, pages 37, 376" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 0.75 inch precipitation depth", "page_or_section": "Bioretention Design Checklist, page 83" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain times in excess of 72 hours should be avoided to prevent mosquito-breeding habitat from forming.", "page_or_section": "2.7 Infiltration Trench, page 51" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a minimum 4ft of separation required between the water table and the bioretention practice", "page_or_section": "2.10 Bioretention, page 77" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "leave at least 4 feet between the seasonal high-water table or bedrock and the trench bottom", "page_or_section": "2.7 Infiltration Trench, page 51" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "ds = planting soil depth (2.5 feet minimum)", "page_or_section": "Bioretention sizing, page 84" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "the length generally exceeding 2:1 (length:width)", "page_or_section": "2.10 Bioretention, pages 80, 84" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 48-hour period", "page_or_section": "Dry Extended Detention Basin, page 40" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 24-hour period", "page_or_section": "Wet Extended Detention Basin, page 41" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide Ohio manual used as MS4 post-construction reference when city PDF unavailable/empty.", "fields_not_found": [] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "cleveland-oh.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": 72, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:55:09.769Z", "enrich_model": "composer-2.5:run-7e6f991a-6fd5-4866-bf97-d93cf74a6db9", "enrich_notes": "Ohio statewide Rainwater and Land Development manual used as Cleveland MS4 proxy. WQv uses 0.75 in precipitation depth; Ohio EPA NPDES requires +20% WQv for sediment. Extended-detention drawdown is 48 h (dry ED basin outlet) vs 24 h (wet ED and wetland ED above permanent pool); general pond WQv storage cited as 24–48 h. Bioretention: min 40 h drawdown (Ohio EPA); full practice drain often 40–72 h. Infiltration trench: infiltrate WQv in 24–48 h; avoid drain >72 h. Sand filter: 40 h total design drawdown. Infiltration trench soil K: 0.52–2.5 in/hr (site tests). Wet permanent pool mean depth 3–6 ft; wetland pool depths often 6–18 in (avg 6–12 in). Bioretention ponding generally <6 in, may be up to 12 in.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "college-station-tx", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/college-station-tx/", "data_url": "https://stormwateratlas.com/data/manuals/college-station-tx.json", "document_metadata": { "jurisdiction_name": "City of College Station", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "iSWM Criteria Manual for Site Development and Construction", "version_or_edition": "Revised January 2015 (December 2009 base)", "adoption_or_effective_date": "2015-01", "last_revised_date": "2015-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 25, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQv) based on 1.5 inches of rainfall (85th percentile storm), not a return-period storm. Option 2: treat WQv by reducing TSS from the development site for runoff from rainfalls up to 1.5 inches. Primary structural controls sized for WQv are expected to remove about 70–80% of annual average TSS load when designed per specifications. Methods to compute WQv referenced to Water Quality Technical Manual Section 1.2.", "peak_flow_calculation_method": [ "Rational Method", "SCS Unit Hydrograph Method", "Streambank Protection: control 1-year, 24-hour storm (Streambank Protection Volume / SPV), including 24-hour extended detention option", "Conveyance: 25-year, 24-hour storm", "Flood Mitigation: 100-year, 24-hour storm", "Downstream assessment required for streambank protection, conveyance, and flood mitigation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Enhanced swales (dry, wet, wetland)", "Detention", "Filter strips", "Sand filters / filter boxes", "Infiltration wells and trenches", "Ponds", "Porous surfaces", "Green roofs", "Rainwater harvesting", "Wetlands", "Submerged gravel wetlands", "Alum treatment", "Proprietary systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "College Station — BCS Drainage Design Manual PDF 404; temporary NCTCOG iSWM / Dallas criteria", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "page 29, Section 3.2.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treat the Water Quality Protection Volume by reducing total suspended solids from the development site for runoff resulting from rainfall of 1.5 inches (85th percentile storm).", "page_or_section": "page 28, Section 3.2.3" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Modular Porous Paver Systems Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet Pond Limit maximum normal pool depth to about 4 ft (dugout)", "page_or_section": "Table 3.19 Physiographic Factors, page 61" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Replace when bcsunited.net publishes a durable Drainage Design Manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://iswm.nctcog.org/Documents/iSWM_Criteria_Manual_01142015.pdf", "landing_page_url": "https://bcsunited.net/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "college-station-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:56:01.564Z", "enrich_model": "composer-2.5:run-7a45b70b-1805-49e6-9a1f-31542d43a7f8", "enrich_notes": "Criteria Manual references Site Development Controls Technical Manual for detailed design criteria. WQv is first 1.5 in rainfall (85th percentile). Primary controls target 70–80% annual TSS removal. Table 3.17/3.4 list practice-specific depth-to-water-table (e.g., bioretention 2 ft, infiltration trenches 4 ft) and infiltration minimum >0.5 in/hr. Proprietary systems require manufacturer data and independent third-party verification (TARP, TAPE, or others cited in TriSWM appendix).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "colorado-springs-co", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/colorado-springs-co/", "data_url": "https://stormwateratlas.com/data/manuals/colorado-springs-co.json", "document_metadata": { "jurisdiction_name": "City of Colorado Springs", "jurisdiction_level": "municipality", "state_code": "CO", "document_title": "Urban Storm Drainage Criteria Manual Volume 3 (MHFD/UDFCD) — regional Front Range reference", "version_or_edition": "November 2015 (Vol.3 Ch.1)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches of precipitation within the MHFD/UDFCD boundary (≈80th percentile storm); remaining runoff after volume reduction treated through capture and slow release of the WQCV. City drainage portals often HTML/403 — Front Range MS4s commonly apply USDCM Volume 3.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grass Buffers / Swales", "Bioretention", "Permeable Pavement", "Extended Detention Basins", "Sand Filters", "Constructed Wetland / Retention Ponds", "Underground / Source Control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Colorado Springs Front Range MS4 — coverage via MHFD/UDFCD Volume 3 WQCV", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches", "page_or_section": "USDCM Vol.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Within the UDFCD boundary, the WQCV is based on runoff from 0.6 inches of precipitation.", "page_or_section": "Chapter 1, Common Stormwater Management Terms, page 11" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention (rain gardens): The use of distributed on-site vegetated features such as rain gardens can help maintain natural drainage patterns", "page_or_section": "Chapter 1, Step 1, page 17" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "permeable pavement systems, bioretention, extended detention basins, sand filters, constructed wetland ponds, and retention ponds", "page_or_section": "Chapter 1, Section 4.2, page 19" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Regional MHFD criteria — prefer city-specific drainage criteria manual when a durable public PDF is available.", "fields_not_found": [] }, "source": { "document_url": "https://www.mhfd.org/files/7af5d4c2f/03_Chapter-1-Stormwater-Management.pdf", "landing_page_url": "https://coloradosprings.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "colorado-springs-co.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:56:21.473Z", "enrich_model": "composer-2.5:run-ac7f43af-7b6e-4532-871f-2df877a02c3c", "enrich_notes": "Corpus is USDCM Vol. 3 Chapter 1 (planning/regulatory). WQCV defined as runoff from 0.6 in. precipitation within UDFCD boundary (~80th percentile storm). Step 2 BMPs named; detailed sizing/dimensions referenced in Chapters 3–5, not in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "columbia-mo", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/columbia-mo/", "data_url": "https://stormwateratlas.com/data/manuals/columbia-mo.json", "document_metadata": { "jurisdiction_name": "City of Columbia", "jurisdiction_level": "municipality", "state_code": "MO", "document_title": "Stormwater Management & Water Quality Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Water Quality Storm = event producing ≤90% of annual 24-hour stormwater runoff volume. WQv = storage to capture and treat 90% of average annual stormwater runoff volume = Water Quality Storm × volumetric runoff coefficient × site area. Channel protection detention and treatment-train BMPs; references APWA/MARC BMP Manual.", "peak_flow_calculation_method": [ "Water quality hydrology methods (Ch. 2)", "Detention/retention methods (Ch. 6)", "Rational / unit peak discharge methods (figures)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Grass swales", "Retention and detention ponds", "Extended detention wetland", "Wet pond (permanent pool for WQv)", "Wetland treatment systems", "Channel protection detention", "Non-structural / treatment train practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF COLUMBIA, MISSOURI", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT & WATER QUALITY MANUAL", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv): The storage needed to capture and treat 90 percent of the average annual stormwater runoff volume", "page_or_section": "§1.6 Definitions" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention: Soil and plant-based stormwater management practices... structural (grass swales, terraces, retention and detention ponds, and others)", "page_or_section": "Definitions / Background" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "water quality storm, 1.3 inches, which constitutes 90% of the average annual rainfall in central Missouri", "page_or_section": "Appendix A, A.1 Overview" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Excavation Depth = 3 feet minimum, Bottom Sand Layer = 6\", Soil Depth = 27 inches, Mulch Depth = 3 inches", "page_or_section": "Appendix A, A.2.1 Design Criteria" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "construct the rain garden such that a flat, 6\" ponding area, the same size as the bottom of the basin", "page_or_section": "Appendix A, A.2.1 Design Criteria item 8" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "An extensive vegetated roof, a minimum of 3\" thick, may be used for buildings", "page_or_section": "Chapter 6, 6.8.3 Small Area BMP" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The design infiltration rate shall be 20% of the rate determined by the soils report", "page_or_section": "Chapter 6, 6.8.2 B. KCBMP Sections 8.1-8.3 item 1" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No clear edition date on cover of extracted text; quantity design storms need deeper Ch. 2/6 pass. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.como.gov/wp-content/uploads/2021/08/City-Stormwater-Management-and-Water-Quality-Manual.pdf", "landing_page_url": "https://www.como.gov/utilities/columbias-stormwater-utility/", "retrieved_at": "2026-08-10T09:39:14.773Z", "original_filename": "columbia-mo.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 27, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:56:56.605Z", "enrich_model": "composer-2.5:run-dfd70589-0f67-4a4f-8f8e-d69875b2945d", "enrich_notes": "WQv tied to Water Quality Storm (≤90% of annual 24-hr runoff volume); Appendix A assigns 1.3 in rainfall depth for central Missouri. Rain garden criteria map to small-area bioretention (27 in planting soil, 6 in ponding). Design infiltration is 20% of soils-report rate (no fixed in/hr). KCBMP referenced for porous pavement and infiltration; Ch. 6 defers to KCBMP on conflicts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "columbia-sc", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/columbia-sc/", "data_url": "https://stormwateratlas.com/data/manuals/columbia-sc.json", "document_metadata": { "jurisdiction_name": "City of Columbia", "jurisdiction_level": "municipality", "state_code": "SC", "document_title": "Best Management Practice (BMP) Design Manual", "version_or_edition": "January 10, 2014", "adoption_or_effective_date": "2014-01-10", "last_revised_date": "2014-01-10", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 25, 100 ], "water_quality_volume_method": "Sites disturbing >1 acre: treat runoff from a 1.2-inch rainfall event (WQv via Unified Stormwater Sizing Criteria / GSMM methods), released over ≥24 hours for detention ponds. Also treat Channel Protection Volume (CPv) for the 1-year storm (≥24-hour release). Overbank flood protection Q25 and extreme flooding addressed. Pretreatment required; commercial/parking >2,000 sf need hydrocarbon capture.", "peak_flow_calculation_method": [ "Unified Stormwater Sizing Criteria (WQv / CPv)", "GSMM Sections 3.2–3.4 for structural BMPs", "Overbank Flood Protection (Q25)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water quality BMPs (GSMM structural controls)", "Detention ponds", "Pretreatment (forebay, micro-pool, filter strips, vault)", "Better site design practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The City of Columbia, Utilities and Engineering Department", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Columbia", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Columbia, South Carolina", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Best Management Practice (BMP) Design Manual", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Georgia Stormwater Management Manual (GSMM) will also be utilized", "page_or_section": "Ch. 1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat at least the runoff from the entire site for a 1.2-inch rainfall event", "page_or_section": "§1 Water Quality" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Channel Protection Volume ... 1-year storm; Overbank Flood Protection (Q25)", "page_or_section": "Ch. 1–2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "permanent water quality BMP ... pretreatment device such as a forebay", "page_or_section": "§1 Water Quality" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Provide extended detention of the 1-year storm event released over a period of 24 hours to reduce bank-full flows and protect downstream channels from erosive velocities and unstable conditions. Overbank Flood Protection Provide peak discharge control of the 25-year storm e", "page_or_section": "pp. 20–21" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Permanent water quality structures not having a permanent pool elevation shall be designed to store the runoff from the contributing area of the site from a 1.2-inch rainfall event", "page_or_section": "1.4.1 Design Requirements, page 14" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = (1.2)(Rv)(A)/12 where: WQv = water quality volume 1.2-inch rainfall (in acre-feet)", "page_or_section": "2.1 Water Quality (WQv), page 23" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Convert the WQV to an area by dividing the WQV by the water quality rainfall depth of 1.2 inches", "page_or_section": "4.2 User Fee Crediting Options, page 57" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "These structures are designed to completely drain to a dry condition within 72 hours.", "page_or_section": "Table 3.1 Accepted quantity controls, page 35" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "release the accumulated water quality volume (WQv) over a minimum period of 24-hours", "page_or_section": "1.4.1 Design Requirements, page 14" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The Channel Protection sizing criterion specifies that 24 hours of extended detention be provided for runoff generated by the 1-year, 24-hour rainfall event", "page_or_section": "2.2 Channel Protection (CPv), page 24" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "This method should be used only for bioretention areas, filter facilities and infiltration trenches where the drawdown time is ≥ 24 hours.", "page_or_section": "3.1.5 Routing with WQv Removed, page 37" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool depths must be ≥ 4 feet to reduce mosquito breeding.", "page_or_section": "Table 3.1 / Table 3.2, pages 35 and 38" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://columbiascwater.net/wp-content/uploads/2018/08/bmpmanual.pdf", "landing_page_url": "https://columbiascwater.net/", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "columbia-sc.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:57:34.110Z", "enrich_model": "composer-2.5:run-17348f8c-1a37-456c-9b7f-459ac3b91b92", "enrich_notes": "Columbia USC uses 1.2-inch rainfall in WQv formula (1.2×Rv×A/12); permanent-pool water quality structures store runoff from a 0.6-inch event. Detailed BMP sizing criteria defer to GSMM Sections 3.2–3.4. Stormwater wetlands (shallow/ED) are not recommended locally.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "columbus-oh", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/columbus-oh/", "data_url": "https://stormwateratlas.com/data/manuals/columbus-oh.json", "document_metadata": { "jurisdiction_name": "City of Columbus", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Stormwater Drainage Manual", "version_or_edition": "June 2025", "adoption_or_effective_date": "2025-08-26", "last_revised_date": "2025-06", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Post-construction stormwater quality controls sized to the Water Quality Volume (WQv) and Water Quality Flow (WQf) per Section 3.3 / 6.2.9, using Ohio EPA Construction General Permit post-construction criteria and Ohio Rainwater and Land Development Manual methods (more stringent of OEPA vs Columbus criteria applies). Combined-sewer discharges are exempt from Section 3.3 water quality controls unless separation/redirection is planned. Extended detention example: release 50% of WQv in 8 hours and 100% of WQv per design tables.", "peak_flow_calculation_method": [ "Rational Method (peak flows; up to 200 acres)", "USGS Regression Equations (streams; ~17–2600 acres)", "NRCS (SCS) Curve Number Method (peak flows up to 640 acres)", "Approved hydrograph methods (required for detention design and downstream analysis)", "Critical storm method for quantity control (Table 3-1): release ≤ critical storm at ≤ 1-year predevelopment peak; 100-year post ≤ 10-year predevelopment peak", "SCS Type II 24-hour design storm hyetograph (Table 2-3) with NOAA Atlas 14 Central Ohio IDF" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Dry detention pond", "Wet detention pond", "Constructed wetland / shallow constructed wetland", "Parking lot storage", "Infiltration basin", "Vegetated filter strips", "Underground detention system", "Permeable pavement", "Bioretention facilities (GI)", "Sand/media filter" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Columbus Stormwater Drainage Manual June 2025 / Division of Sewerage and Drainage", "page_or_section": "Cover / headers" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Columbus Stormwater Drainage Manual June 2025 / Division of Sewerage and Drainage", "page_or_section": "Cover / headers" }, { "field": "document_metadata.state_code", "excerpt": "Ohio EPA Construction General Permit / Rainwater and Land Development Manual", "page_or_section": "Section 3.3 / Definitions" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Drainage Manual", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective August 26, 2025, the 2024 Stormwater Drainage Manual and the 1994 Erosion", "page_or_section": "Preface / Effective date" }, { "field": "document_metadata.last_revised_date", "excerpt": "Stormwater Drainage Manual List of Updates June 2025", "page_or_section": "List of Updates" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The design criteria provided in this section are in addition to the criteria detailed in the Ohio Construction General Permit and the Ohio Rainwater and Land Development Manual.", "page_or_section": "Section 3.3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Type II 24-Hour Distribution Rainfall (in) Frequency: 100-yr 50-yr 25-yr 10-yr 5-yr 2-yr 1-yr", "page_or_section": "Table 2-3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Critical Storm Determination … 1-year, 2-year, 5-year, 10-year, 25-year, 50-year, 100-year", "page_or_section": "Table 3-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All runoff from development sites shall be directed to one or more stormwater quality controls designed according to: 1. Appropriate currently effective Ohio EPA Authorization for Stormwater Discharges Associated with Construction Activity… 3. Appropriate currently effective Ohio Rainwater and Land Development Manual, and 4. Criteria provided in Section 3.", "page_or_section": "Section 3.3.1.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv Water Quality Volume / Method used for calculating the Water Quality Volume (WQv)", "page_or_section": "Acronyms / Table 2-2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For extended detention, release 50% WQv in 8 hours and release 100% WQv", "page_or_section": "Section 3 bioretention/extended detention design table" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The City allows three methods for calculating stormwater runoff peak flows: 1. The Rational Method… 2. USGS Regression Equations… 3. The Natural Resources Conservation Service (NRCS… Curve Number method…", "page_or_section": "Section 2.2.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Runoff from storm events less than or equal to the critical storm event shall be released from the site at a rate no greater than the peak runoff during a 1-year storm event under pre-developed conditions. Additionally, the peak runoff rate during the 100-year storm event shall be released at a rate less than or equal to the peak runoff rate during the 10-year storm event under pre-developed conditions", "page_or_section": "Section 3.2.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Design rainfall hyetographs distributed over a 24-hour period with the SCS Type II distribution are presented in Table 2-3.", "page_or_section": "Section 2.2.2.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infrastructure Surface Controls Dry Detention Pond ● ● • OEPA CGP/Supplements • Columbus SWDM Wet Detention Pond ● ● • OEPA CGP/Supplements • Columbus SWDM Constructed Wetland ● ● • OEPA CGP/Supplements • Columbus SWDM Shallow Constructed Wetland ● ● • OEPA CGP/Supplements •", "page_or_section": "pp. 109–110" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Areas of facilities outside the permanent pool shall be designed to drain completely toward the outlet or permanent pool within 72 hours of a precipitation event.", "page_or_section": "Section 3.1 j.i (pages 106-107)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "For extended detention, release 50% WQv in 8 hours and release 100% WQv in 24 hours", "page_or_section": "Table 3-4, Section 3.4.10 (page 140)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum length-to-width ratio for a constructed wetland shall be 3:1.", "page_or_section": "Section 3.4.9.1 item 2 (page 132)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "June 2025 Columbus SWDM. Explicit WQv rainfall depth equation is deferred to OEPA CGP / Rainwater and Land Development Manual rather than restated as a single Columbus-only formula in Section 3.3. No named proprietary modeling package is mandated (methods are specified). Manual text: effective August 26, 2025. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.columbus.gov/files/sharedassets/city/v/2/utilities/documents/sewer-publications/2025-stormwater-drainage-manual.pdf", "landing_page_url": "https://www.columbus.gov/Services/Columbus-Water-Power/Information-for-Customers/Public-Utility-Contractors/Stormwater-Drainage-Manual", "retrieved_at": "2026-08-10T07:45:00.000Z", "original_filename": "columbus-oh.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:58:16.302Z", "enrich_model": "composer-2.5:run-b0d7e1a5-3030-44d7-abdd-2ee779a5cbf6", "enrich_notes": "WQv rainfall depth is not restated in Columbus Section 3.3; sizing references OEPA CGP and Ohio Rainwater and Land Development Manual. Shallow constructed wetlands Table 3-4 specifies minimum length-to-width 2:1 (3:1 preferred); full constructed wetlands Section 3.4.9.1 require minimum 3:1. Extended-detention release criteria also specify 50% WQv in 8 hours (Table 3-4). Wet detention open-water depths are 4–12 ft average (range, not a single design depth). Bioretention filter media depth deferred to Supplemental Specification 1604 (not in excerpts).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "concord-nc", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/concord-nc/", "data_url": "https://stormwateratlas.com/data/manuals/concord-nc.json", "document_metadata": { "jurisdiction_name": "City of Concord", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (City MS4 / LDO)", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Concord MS4 follows NCDEQ Stormwater Design Manual MDC. Combined SCM design volume handles the required storm depth for the applicable stormwater program (e.g., 1\" for runoff treatment under Rule 15A NCAC 02H .1021(6) in non-coastal HQW/ORW zones).", "peak_flow_calculation_method": [ "NCDEQ MDC 10-year outlet erosion protection" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "SCM devices per 15A NCAC 02H .1051–.1062" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" }, { "field": "practice_mentions.bioretention", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.swale", "excerpt": "vegetated swales, level spreader-filter strips, and berms", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.wet_pond", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice at the invert", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice at the invert", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NCDEQ Design Manual (Cary/High Point pattern).", "fields_not_found": [] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.deq.nc.gov/about/divisions/energy-mineral-and-land-resources/stormwater/stormwater-program/stormwater-design-manual", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "concord-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:58:37.479Z", "enrich_model": "composer-2.5:run-4034293a-bc4b-430d-9d34-3115601360da", "enrich_notes": "Corpus is NCDEQ C-0 General MDC only (pages 2–7); device-specific MDC under Rules .1051–.1062 and Part C are referenced but not included. Required storm depth 1 inch is cited via Rule 15A NCAC 02H .1021(6) for non-coastal HQW/ORW runoff treatment. MDC 6 requires a drawdown method but no maximum drawdown time in hours.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "concord-nh", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/concord-nh/", "data_url": "https://stormwateratlas.com/data/manuals/concord-nh.json", "document_metadata": { "jurisdiction_name": "City of Concord", "jurisdiction_level": "municipality", "state_code": "NH", "document_title": "New Hampshire Model Stormwater Standards / NH Stormwater Manual", "version_or_edition": "Draft: May, 2025", "adoption_or_effective_date": null, "last_revised_date": "2025-05", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 50, 100 ], "water_quality_volume_method": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall, Rv = 0.05 + 0.9(I), A = total site area draining to the structure.", "peak_flow_calculation_method": [ "TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "raingardens", "bioretention systems", "tree box filters", "subsurface gravel wetlands", "filtration practices", "infiltration practices", "swales", "detention areas" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "USDA/NRCS hydrologic soil group, as follows: Hydrologic Group Rd (inches) A 0.40 B 0.25 C 0.10 D 0.00 Channel Protection Volume (CPV) If the 2-year, 24-hour post-development storm volume does not increase due to development then: control the 2-year, 24-hour post-development p", "page_or_section": "pp. 10–11" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall", "page_or_section": "NH Model Stormwater Standards" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = (P)(Rv)(A) P = 1 inch of rainfall", "page_or_section": "Table 1, pages 10-11" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "onsite retention of the first 1-inch of rainfall based on hydrologic soil group (HSG)", "page_or_section": "Element C.2.a, page 4" }, { "field": "practice_mentions.bioretention", "excerpt": "enhanced stormwater SCMs (such as raingardens, bioretention systems, tree box filters, and similar stormwater management landscaping techniques)", "page_or_section": "Element C.1.b, page 3" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "natural, vegetated filtration and/or infiltration practices or subsurface gravel wetlands for water quality treatment is preferred", "page_or_section": "Element C.2.b, page 4" }, { "field": "practice_mentions.swale", "excerpt": "GIS files containing the coordinates of all stormwater infrastructure elements (e.g. catch basins, swales, detention/bioretention areas, piping)", "page_or_section": "Element D.1.d, page 5" }, { "field": "practice_mentions.extended_detention", "excerpt": "catch basins, swales, detention/bioretention areas, piping", "page_or_section": "Element D.1.d, page 5" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "filtration and/or infiltration practices", "page_or_section": "Element C.2.b and E.4.a, pages 4 and 7" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NH Model Stormwater Standards (Manchester pattern).", "fields_not_found": [] }, "source": { "document_url": "https://extension.unh.edu/sites/default/files/media/2025-06/stormwater-management-standards.pdf", "landing_page_url": "https://extension.unh.edu/stormwater-center/nh-stormwater-manual", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "concord-nh.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T07:58:47.180Z", "enrich_model": "composer-2.5:run-5c4ba200-456c-4687-b37e-fd30c225291e", "enrich_notes": "Concord adopts NH Model Stormwater Standards (May 2025 draft). WPS/WQV uses P=1 inch; detailed SCM sizing references UNH Stormwater Center tool and NH Stormwater Manual. Table 1 GRV recharge depths by HSG: A 0.40 in, B 0.25 in, C 0.10 in, D 0.00 in. Water quality fallback: ≥90% TSS, ≥60% TN and TP (new dev); redevelopment also cites ≥50% TN. Peak control: 10- and 50-year 24-hr storms; channel protection per Table 1 CPV rules.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "corpus-christi-tx", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/corpus-christi-tx/", "data_url": "https://stormwateratlas.com/data/manuals/corpus-christi-tx.json", "document_metadata": { "jurisdiction_name": "City of Corpus Christi", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Drainage Design Manual", "version_or_edition": "December 2024", "adoption_or_effective_date": null, "last_revised_date": "2024-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "Chapter 9 Water Quality / Water Quality Protection; Chapter 11 general water quality management approach. Detention analysis Chapter 7 including design rainfall events for detention and stormwater retention (7.8).", "peak_flow_calculation_method": [ "Detention analysis and design rainfall events for detention (Chapter 7)", "Street/roadway level of protection including 25-year and 100-year criteria", "Supports Infrastructure Design Manual (IDM) policies" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention basins", "Stormwater retention", "Water quality protection practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF CORPUS CHRISTI", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Corpus Christi", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Corpus Christi", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "DRAINAGE DESIGN MANUAL", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "DECEMBER 2024", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "Updated December 2024", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "APPENDIX TO THE INFRASTRUCTURE DESIGN MANUAL", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "25-year / 100-year design storm", "page_or_section": "Level of protection" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Protection", "page_or_section": "Section 9.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Design Rainfall Events For Detention", "page_or_section": "Section 7.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin Design / Stormwater Retention", "page_or_section": "Chapter 7" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality control volume (WQCV) that is recommended for control is the first half inch (0.5 inches) of runoff from the basin tributary to the BMP", "page_or_section": "Chapter 11 – 11.4.3 Water Quality Control Volume; page 178" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The water quality control volume shall be detained over at least a 24-hour period, and preferably for longer.", "page_or_section": "Chapter 11 – 11.4.3; page 178" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of 3 feet between the bottom of the infiltration trench and the groundwater table is recommended.", "page_or_section": "Chapter 11 – 11.4.4.7 Infiltration Trenches; page 205" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Minimum of 3 feet between stone reservoir level and seasonally high-water table.", "page_or_section": "Chapter 11 – 11.4.4.8 Porous Pavement; page 210" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "A 40-hour drain time for the WQCV is recommended to remove a significant portion of fine particulates and provide stream bank erosion control.", "page_or_section": "Chapter 11 – 11.4.4.1 Extended Dry Detention Basins; page 179" }, { "field": "practice_mentions.extended_detention", "excerpt": "Extended dry detention (EDD) basins are designed to completely empty at some time after storm water runoff ends.", "page_or_section": "Chapter 11 – 11.4.4.1; page 179" }, { "field": "practice_mentions.sand_filter", "excerpt": "Final sand bed depth shall be at least 18 inches.", "page_or_section": "Chapter 11 – 11.4.4.6 Sand Filters; page 201" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The soil infiltration rate shall be between 0.5 and 2.4 inches per hour.", "page_or_section": "Chapter 11 – 11.4.4.7; page 205" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Stone reservoir shall be designed to completely drain within a maximum of 2 to 3 days after design storm event", "page_or_section": "Chapter 11 – 11.4.4.8; page 210" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "The detention facility shall have at least a 24 hour drain period for the design storm.", "page_or_section": "Chapter 11 – 11.4.4.3 Constructed Wetlands; page 187" }, { "field": "practice_mentions.bioretention", "excerpt": "Installation of Rain Gardens & Bioretention Areas", "page_or_section": "Chapter 11 – nonstructural BMP list; page 177" }, { "field": "practice_mentions.swale", "excerpt": "5-year design storm must be contained in roadside swales", "page_or_section": "Chapter 2 – 2.7.1 Streets and Roadways; page 17" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Corpus Christi DDM Dec 2024 labeled draft appendix to IDM.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.corpuschristitx.gov/media/ln5lofdo/draft-drainage-design-manual.pdf", "landing_page_url": "https://www.corpuschristitx.gov/department-directory/engineering-services/infrastructure-design-manual/", "retrieved_at": "2026-08-10T08:08:51.648Z", "original_filename": "corpus-christi-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 40, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:59:34.197Z", "enrich_model": "composer-2.5:run-2dc6dbd9-b558-4fa8-b180-95a2cfb717e7", "enrich_notes": "WQCV is defined as the first 0.5 inch of tributary runoff (Chapter 11.4.3), with minimum 24-hour detention of that volume. Extended dry detention recommends 40-hour WQCV drain time. Infiltration trenches and porous pavement both recommend 3 ft minimum separation from groundwater/seasonal high water table. Porous pavement reservoir drain is stated as 2–3 days maximum (not a single hour value). Sand filters require at least 18 inches sand bed depth. Infiltration trench soil infiltration suitability range is 0.5–2.4 in/hr; porous pavement requires soil rate >0.27 in/hr and design rate at half of measured rate (no single numeric design rate).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "davenport-ia", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/davenport-ia/", "data_url": "https://stormwateratlas.com/data/manuals/davenport-ia.json", "document_metadata": { "jurisdiction_name": "City of Davenport", "jurisdiction_level": "municipality", "state_code": "IA", "document_title": "SUDAS Design Manual — Chapter 2 Stormwater (city uses SUDAS + ISWMM)", "version_or_edition": "Chapter 02 (SUDAS Design Manual)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Davenport follows statewide SUDAS Design Manual Chapter 2 and Iowa Stormwater Management Manual (ISWMM) for post-construction practices. SUDAS defines Water Quality Volume (WQv) and Recharge Volume (Rev) plus conveyance/detention (2G); ISWMM guides practice sizing.", "peak_flow_calculation_method": [ "Minor design storm (generally 2- to 10-year) for conveyance", "Major design storm (typically 100-year) for flood routing", "Detention basin design methods (Section 2G)", "ISWMM criteria for post-construction practices" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention practices", "Storm sewer / intake conveyance", "Water quality / recharge volume practices (ISWMM)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Davenport uses SUDAS Design Manual / ISWMM", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume, WQv / ISWMM Design Standards", "page_or_section": "SUDAS Ch.2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For Iowa, this equates to providing water quality treatment for the runoff resulting from a rainfall depth of 1.25 inches or less.", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 (page 9)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Channel Protection Storage Volume, Cpv — Provide 24 hours of extended detention of the runoff from the 1 year 24 hour duration storm event", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 (page 9)" }, { "field": "practice_mentions.swale", "excerpt": "Open Channel Flow - Swales and Ditches: 1) Describe swale and ditch design.", "page_or_section": "2A-4 Project Drainage Report, 4.d (page 22)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1 year 24 hour duration storm event", "page_or_section": "2A-1 Table 2A-1.01 (page 9)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SUDAS + ISWMM (Cedar Rapids pattern).", "fields_not_found": [] }, "source": { "document_url": "https://www.iowasudas.org/wp-content/uploads/sites/15/2020/03/Chapter_02.pdf", "landing_page_url": "https://iowasudas.org/manuals/design-manual/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "davenport-ia.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T08:01:23.290Z", "enrich_model": "composer-2.5:run-c9c20956-f09f-40dd-b61c-e9f453792174", "enrich_notes": "SUDAS Chapter 2 states stormwater quality practice design is not in this manual; refer to Iowa Stormwater Management Manual (ISWMM). Provided excerpts define unified sizing only: Iowa WQv rainfall depth 1.25 inches (90% of storms) and Channel Protection Volume as 24 hours extended detention for 1-year 24-hour runoff. Detention basin outlet guidance mentions orifice for water quality and 2-year low flows but no BMP-specific numeric criteria in corpus.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dayton-oh", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dayton-oh/", "data_url": "https://stormwateratlas.com/data/manuals/dayton-oh.json", "document_metadata": { "jurisdiction_name": "City of Dayton", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Department of Water Engineering Design Standards — Section 5 Storm Water Requirements", "version_or_edition": "October 2020", "adoption_or_effective_date": "2020-10-01", "last_revised_date": "2020-10-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 25, 50, 100 ], "water_quality_volume_method": "Peak-rate control: post-development peak runoff ≤ pre-development for all 24-hour storms from 1-year through the critical year storm; detention volume methods based on percent increase in 1-year 24-hour runoff volume. Post-construction BMPs per Ohio EPA Construction General Permit OHC000002 (SWP3 Part III) with O&M manuals required. Section is conveyance/detention focused rather than a standalone WQv rainfall-depth manual.", "peak_flow_calculation_method": [ "Major waterways (>4 sq mi): 100-year", "Secondary (1–4 sq mi): 50-year", "Minor (≤1 sq mi open channels): 25-year", "Detention: post ≤ pre for 24-hr storms 1-year through critical year", "Runoff curve numbers / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention basins", "Retention basins", "Storm sewer / closed conduits", "Open channels", "Post-construction BMPs per Ohio EPA CGP", "Dry wells (limited / geotech)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Dayton Engineering Design Standards", "page_or_section": "Section 5" }, { "field": "document_metadata.version_or_edition", "excerpt": "October 2020", "page_or_section": "Header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Major waterways ... 100 years ... Secondary ... 50 years ... Minor ... 25 years", "page_or_section": "§5.1 A" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "post-development peak rate of runoff does not exceed that of the pre-development stage, for all 24-hour storms ... Post Construction Storm Water Management requirements ... Ohio EPA Permit No.: OHC000002", "page_or_section": "§5.1 D / §5.6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Section 5.4 Detention/Retention Basins ... post construction BMPs", "page_or_section": "§5.4 / §5.6" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The lake area should be an average depth of at least approximately 4 feet to inhibit weed and insect growth", "page_or_section": "Section 5.4 C.1 Recommendations for Basins Containing Permanent Water, page 7" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry detention basins should be designed to minimize ponding so that water does not remain standing in the bottom", "page_or_section": "Section 5.4 B Recommendations for Dry Detention Basins, page 7" }, { "field": "practice_mentions.wet_pond", "excerpt": "retention basins containing permanent lakes should have a water area of at least one-half acre", "page_or_section": "Section 5.4 C.1, page 7" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Section 5 only (11 pages); not a full multi-volume BMP design manual. HEAD 404 but GET works. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.daytonohio.gov/DocumentCenter/View/4875", "landing_page_url": "https://www.daytonohio.gov/", "retrieved_at": "2026-08-10T09:39:14.776Z", "original_filename": "dayton-oh.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "wet_pond" ], "enriched_at": "2026-08-13T08:01:47.756Z", "enrich_model": "composer-2.5:run-a9f8e6b7-0f9f-42c1-94cb-08c683136278", "enrich_notes": "Section 5 is peak-rate detention and conveyance (TR-55, critical storm table); no WQv rainfall depth. Post-construction BMPs defer to Ohio EPA CGP OHC000002 SWP3 Part III with O&M manuals—no facility-specific BMP sizing in this section. Retention lakes: ~4 ft average depth for weed/insect control; dry detention emphasizes minimizing standing water (0.50% bottom slope with low-flow channel/underdrain, or 2.00% minimum bottom slope)—no drawdown hours stated.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "daytona-beach-fl", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/daytona-beach-fl/", "data_url": "https://stormwateratlas.com/data/manuals/daytona-beach-fl.json", "document_metadata": { "jurisdiction_name": "City of Daytona Beach", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Jacksonville Land Development Procedures Manual Volume 2 (SJRWMD-region municipal pattern)", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "SJRWMD ERP AH Vol II PDF not publicly fetchable (403). Using Jacksonville LDPM Vol 2 wet detention / SMF pattern as east-central Florida municipal reference: wet detention and stormwater management facilities per Table 3.7-1; MSMP 2070 rainfall depths for multi-return-period 24-hour storms. Prefer SJRWMD AH Vol II when a durable PDF is available.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage contexts", "Design rainfall depths from MSMP 2070" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Daytona Beach (SJRWMD) — coverage via Jacksonville LDPM Vol 2 pattern", "page_or_section": "Coverage note" }, { "field": "max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 Grassed Conveyance Swales, Recovery (page 109)" }, { "field": "max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3, Recovery Requirements (page 110)" }, { "field": "max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 Shallow Bioretention, Recovery (page 121)" }, { "field": "shwt_separation_inches", "excerpt": "Shallow Water Table: To receive pollutant-load-reduction credits, the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3, Implementation Considerations (page 109)" }, { "field": "shwt_separation_inches", "excerpt": "Shallow Water Table: SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 Shallow Bioretention (page 121)" }, { "field": "shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.1 General, Physical Constraints (page 123)" }, { "field": "swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3 Design Criteria (page 109)" }, { "field": "swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3 Sizing Requirements (page 112)" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Canonical SJRWMD special_district record: fl-sjrwmd-erp-ah2. Placeholder pending durable SJRWMD AH Vol II or city design-manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.sjrwmd.com/documents/permitting/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "daytona-beach-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:02:09.195Z", "enrich_model": "composer-2.5:run-7e7d181c-e2b7-4323-aa9d-e484ea0a985e", "enrich_notes": "Corpus is City of Jacksonville LDPM Vol. 2 (Jan 2026) used as east-central Florida municipal proxy for Daytona Beach; SJRWMD ERP stormwater quality (e.g., 3-year/1-hour percolation requirements for swales) is referenced throughout. Pond infiltration design uses double-ring infiltrometer at basin bottom with safety factor of 2 (Section 3.7). Swale design infiltration is capped at half field-measured rate (ASTM D3385-09); example uses FS=2 yielding 12 in/hr from 36 in/hr field rate—site-specific, not a manual default rate. Pervious pavement maintenance triggered when installed test rate is below 1.5 in/hr. Wet detention sizing example cites ERP Applicant's Handbook (March 2010 draft) residence-time equations.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "deltona-fl", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/deltona-fl/", "data_url": "https://stormwateratlas.com/data/manuals/deltona-fl.json", "document_metadata": { "jurisdiction_name": "City of Deltona", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Jacksonville Land Development Procedures Manual Volume 2 (SJRWMD-region municipal pattern)", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "SJRWMD ERP AH Vol II PDF not publicly fetchable (403). Using Jacksonville LDPM Vol 2 wet detention / SMF pattern as east-central Florida municipal reference: wet detention and stormwater management facilities per Table 3.7-1; MSMP 2070 rainfall depths for multi-return-period 24-hour storms. Prefer SJRWMD AH Vol II when a durable PDF is available.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage contexts", "Design rainfall depths from MSMP 2070" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Deltona (SJRWMD) — coverage via Jacksonville LDPM Vol 2 pattern", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 Grassed Conveyance Swales (Recovery)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3 Recovery Requirements" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 Shallow Bioretention (Recovery)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3 Implementation Considerations" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 Shallow Bioretention" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.1 Physical Constraints" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3 Design Criteria" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3 Sizing Requirements" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Longitudinal slope between 0.5 percent and 3 percent.", "page_or_section": "Section 4.3 Design Criteria" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Canonical SJRWMD special_district record: fl-sjrwmd-erp-ah2. Placeholder pending durable SJRWMD AH Vol II or city design-manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.sjrwmd.com/documents/permitting/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "deltona-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:05:36.866Z", "enrich_model": "composer-2.5:run-0e588a06-44ec-4550-8a53-566fcdd81b0b", "enrich_notes": "Corpus is Jacksonville LDPM Vol 2 (Deltona proxy). Swale WQ sizing references SJRWMD 3-year/1-hour storm percolation requirements; wet detention example uses 1-inch and 2.5-inch treatment-volume depths and residence time in days (not hours). Infiltration-dependent designs use half of field-measured rate (swales) or safety factor of 2 (detention basin bottom tests)—no single jurisdiction-wide design infiltration rate.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "denton-tx", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/denton-tx/", "data_url": "https://stormwateratlas.com/data/manuals/denton-tx.json", "document_metadata": { "jurisdiction_name": "City of Denton", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Design Criteria Manual", "version_or_edition": "Published July 2024 (effective July 1, 2024)", "adoption_or_effective_date": "2024-07-01", "last_revised_date": "2024-07-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Section 4 Stormwater Design Criteria covers system design, detention facilities, and Water Quality Protection Volume (4.13). City criteria incorporate NCTCOG iSWM Technical Manuals (Planning, Water Quality, Hydrology, Hydraulics, Site Development Controls) with Denton-specific superseding provisions.", "peak_flow_calculation_method": [ "iSWM Hydrology / Hydraulics technical manuals", "Detention facility design (above-grade, underground, parking lot, pumped)", "100-year fully developed water surface elevation criteria", "Post-construction water quality control structures" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention facilities", "Post-construction water quality controls", "iSWM site development controls / BMPs", "Stormwater conveyance systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Design Criteria Manual of the City of Denton, Texas", "page_or_section": "1.1.1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Denton", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Design Criteria Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Published: July 2024", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "effective on July 1, 2024", "page_or_section": "1.1.2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "iSWM Technical Manuals / City stormwater criteria supersede iSWM where conflicting", "page_or_section": "Section 4 intro" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year water surface elevation based on fully developed conditions", "page_or_section": "Section 4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "4.13.1 Water Quality Protection Volume", "page_or_section": "Section 4.13" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "4.9 Detention Facilities / iSWM Hydrology Technical Manual", "page_or_section": "Section 4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Facilities / Post-Construction Water Quality Control", "page_or_section": "4.9 / 4.13" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "\"Water Quality\" Criteria based on a volume of 1.5 inches of rainfall, not storm frequency", "page_or_section": "Table 4.3-A, Section 4.3 Design Storms, page 34" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Outlet structures shall be designed to provide a minimum dewatering time of 36 hours and a maximum dewatering time of 72 hours.", "page_or_section": "Section 4.13.4 Construction Erosion and Sediment Control Requirements, page 73" }, { "field": "practice_mentions.extended_detention", "excerpt": "For water quality, refer to Section 2.2.3 for design of extended detention outlets.", "page_or_section": "Section 4.9.6 Outlet Structures for Detention Facilities, page 66" }, { "field": "practice_mentions.swale", "excerpt": "Open channels, including all natural or improved channels, swales, and ditches shall be designed for the \"Flood Mitigation\" storm event.", "page_or_section": "Section 4.6.3 Open Channels, page 55" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "2024 DCM Section 4 stormwater; iSWM referenced. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.cityofdenton.com/DocumentCenter/View/13450/Design-Criteria-Manual-2024", "landing_page_url": "https://www.cityofdenton.com/255/Development-Code-Design-Documents-Criter", "retrieved_at": "2026-08-10T08:56:34.266Z", "original_filename": "denton-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T08:06:03.237Z", "enrich_model": "composer-2.5:run-69144dfc-6092-4987-ab19-7640c0a62a0b", "enrich_notes": "Water Quality storm is defined as 1.5 inches of rainfall volume (Table 4.3-A), not a frequency event. WQ compliance may infiltrate the water quality volume or remove 80% TSS from Water Quality storm discharge (Section 4.2.3). Detention outlet design references iSWM Hydraulics TM Section 2.2.3 for extended detention outlets (Section 4.9.6). Construction sediment basins require outlet dewatering between 36 and 72 hours (Section 4.13.4). Open channel design includes swales designed for Flood Mitigation storm (Section 4.6.3).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "detroit-mi", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/detroit-mi/", "data_url": "https://stormwateratlas.com/data/manuals/detroit-mi.json", "document_metadata": { "jurisdiction_name": "City of Detroit", "jurisdiction_level": "municipality", "state_code": "MI", "document_title": "Stormwater Management Design Manual", "version_or_edition": "July 2025", "adoption_or_effective_date": "2025-07", "last_revised_date": "2025-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Treat or retain the 90th-percentile annual non-exceedance storm (1.0 inch) over the Regulated Area: (1) remove 80% TSS from uncontrolled post-construction runoff during a 1.0-inch rain event, or (2) effluent TSS ≤80 mg/L, or (3) Volume Control—retain (infiltrate or store/reuse) 1.0 inch of runoff over the Regulated Area (meeting retention automatically satisfies TSS). MS4 Channel Protection also requires the larger of 1.0-inch retention or volume needed to limit 2-year/24-hour runoff to pre-development. Flood control: post-construction peak ≤0.15 cfs/acre for the 10-year/24-hour (<5 ac Regulated Area) or 100-year/24-hour (≥5 ac).", "peak_flow_calculation_method": [ "Rational Method", "Modified Rational Method", "Simple Method (1-inch and 1.9-inch retention/extended detention volumes)", "NRCS Curve Number Approach", "Small Storm Hydrology", "NRCS Midwest-Southeast (MSE) Type 3 rainfall distribution", "EPA SWMM / SWMM-based hydrograph routing" ], "required_hydrologic_hydraulic_software": [ "EPA SWMM", "HydroCAD", "StormCAD", "HEC-HMS", "TR-55", "TR-20" ], "approved_bmp_categories": [ "Detention Practices (basic detention basins, extended dry detention, extended wet detention)", "Bioretention (including bioswales and tree box filters)", "Infiltration Practices (infiltration basins and trenches)", "Permeable Pavement (porous asphalt, pervious concrete, pervious pavers, grid pavement)", "Rainwater Harvesting / Cisterns", "Living Roofs and Walls (green roofs and walls)", "Stormwater Wetlands", "Manufactured Treatment Devices (hydrodynamic separators and filtering systems)", "Trees for Stormwater Management / Green Space" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The City of Detroit Water and Sewerage Department", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The City of Detroit's Stormwater Management Design Manual (Design Manual) encompasses the engineering methods and technical standards that Detroit's development community and property owners need", "page_or_section": "Chapter 1, Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "EGLE: Michigan Nonpoint Source Best Management Practices (BMP) Manual", "page_or_section": "Chapter 1, Page 1-8" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT DESIGN MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "July 2025 • Chapter 1: Pages 1-3, 1-5 • Chapter 2: Pages 2-6...", "page_or_section": "Design Manual Edit History" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Although this Design Manual is the only technical resource crafted specifically for Detroit's PCSWMO compliance, there are other stormwater management resources with a statewide perspective... The information contained within the manual is informational only and should not be construed as requirements for Detroit's PCSWMO.", "page_or_section": "Chapter 1, Section 1.4, Pages 1-8 to 1-9" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 4-1 Precipitation Depths* (inches) for Recurrence Interval (years) Duration 1 year 2 year 5 year 10 year 25 year 50 year 100 year", "page_or_section": "Chapter 4, Table 4-1, Page 4-2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Post-construction peak flow rate shall not exceed the pre-development peak flow rate for the 2-year, 24-hour storm", "page_or_section": "Chapter 2, Table 2-2, Page 2-5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Peak Flow < 5 acres Post-construction peak flow rate shall not exceed 0.15 cfs/acre for the 10-year, 24-hour storm... Peak Flow ≥ 5 acres ... 100-year, 24-hour storm", "page_or_section": "Chapter 2, Table 2-3, Page 2-6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "TSS Control (1) Remove 80% of the total suspended solids (TSS) projected to be in uncontrolled runoff from the Regulated Area in the post-construction condition during a 1.0-inch rain event, or; (2) Have an effluent TSS concentration of less than or equal to 80 mg/L ... or; (3) Satisfy the Volume Control requirement below; this automatically meets the TSS requirement. Volume Control Retain* the runoff volume generated by 1.0 inch over the Regulated Area", "page_or_section": "Chapter 2, Table 2-1, Page 2-5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "In combined sewer areas, regulated construction activities must treat the 90-percent annual non-exceedance storm (1.0 inch). This water quality volume must be treated to (1) remove 80 percent of the total suspended solids (TSS)... Water Quality Volume The volume of stormwater runoff generated by the 90th percentile storm over the Regulated Area of a Development Site (1.0 inch).", "page_or_section": "Chapter 2, Pages 2-9 to 2-10" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Volume Control: Retain and infiltrate the first one (1) inch of rainfall over the Regulated Area or retain and infiltrate the volume necessary to limit the 2-year/24-hour rainfall volume to existing pre-development conditions over the Regulated Area (choose option that results in the higher volume)", "page_or_section": "Chapter 2, Table 2-4, Page 2-6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Table 4-5 Computational Methods... Rational Method, EPA SWMM, HydroCAD, StormCAD... Simple Method for 1-inch storm... Modified Rational Method... NRCS Curve Number Approach, EPA SWMM, HEC-HMS, TR-55, TR-20", "page_or_section": "Chapter 4, Table 4-5, Page 4-9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For the Detroit area, a NRCS Midwest-Southeast (MSE) Type 3 rainfall distribution shall be used.", "page_or_section": "Chapter 4, Section 4.1.3, Page 4-4" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Rational Method, EPA SWMM, HydroCAD, StormCAD, or other DWSD-approved model... NRCS Curve Number Approach, EPA SWMM, HEC-HMS, TR-55, TR-20, HydroCAD, StormCAD, or other DWSD-approved model", "page_or_section": "Chapter 4, Table 4-5, Page 4-9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 7 – Detention Practices... Chapter 8 – Bioretention... Chapter 9 – Infiltration Practices... Chapter 10 – Permeable Pavement... Chapter 11 – Water Harvesting... Chapter 12 – Green Roofs and Walls... Chapter 13 – Stormwater Wetlands... Chapter 14 – Manufactured Treatment Devices... Chapter 15 – Trees for Stormwater Management", "page_or_section": "Chapter 1, Section 1.3 / Table of Contents, Pages 1-6 to 1-8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Benefits Economic Benefits Bioretention and Rain Gardens Cisterns Green Roofs Permeable Pavements Trees and Green Space Remove Impervious Cover 1.3 Chapter Overview of This Design Manual The descriptions below provide an overview of each chapter in this Design Manual", "page_or_section": "p. 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Retention volume based on 1 inch of rainfall on the Regulated Area", "page_or_section": "2-43, Chapter 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "fee in-lieu for any of the following required SCM volumes: retention (1.0inch volume control)", "page_or_section": "2-13, Chapter 2" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Groundwater level at least 2 vertical feet below the bottom of potential infiltration BMP?", "page_or_section": "2-43, Chapter 2" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Two feet is the minimum allowable distance but may reduce the performance of the practice.", "page_or_section": "8-25, Chapter 8 – Depth to Groundwater (from bottom of practice)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "maximum allowable surface ponding depth of 12 inches", "page_or_section": "2-47, Chapter 2" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The most common depth of the surface ponding layer ... is 12 inches, which corresponds to the maximum allowable ponding depth", "page_or_section": "8-18, Chapter 8" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended detention includes a 48-hour discharge of the runoff volume generated from 1.9 inches of rainfall.", "page_or_section": "2-11, Appendix 2A area" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The extended detention hydraulic control shall be designed to provide a drawdown time of 48 hours for the VED.", "page_or_section": "2-44, Chapter 2" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Depth of permanent pool Minimum of 3 feet", "page_or_section": "7-32, Table 7 – Extended Wet Detention" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio Minimum of 3:1 for extended dry detention practices", "page_or_section": "7-33, Chapter 7 Layout table" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Extracted from local samples/queue/detroit-mi.txt (OCR/extraction truncates after mid-manual with garbage bytes; Chapters 1–4 and TOC BMP chapters were available). Performance standards and hydrologic methods are explicit. SEMCOG LID / EGLE BMP manuals are referenced as informational only—not adopted as Detroit requirements. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://detroitmi.gov/sites/detroitmi.localhost/files/2025-08/2025%20DWSD%20SW%20Design%20Manual.pdf", "landing_page_url": "https://detroitmi.gov/document/stormwater-management-design-manual", "retrieved_at": "2026-08-08T10:41:43.274Z", "original_filename": "detroit-mi.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": 48, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:07:09.477Z", "enrich_model": "composer-2.5:run-2d6097bc-03bc-4436-8f2a-0e8bbb4a84a1", "enrich_notes": "WQv/retention is explicitly 1.0 inch on the Regulated Area. Extended detention (onsite alternative) uses VED with 48-hour drawdown and 1.9-inch rainfall basis for discharge volume. Minimum groundwater separation is stated as 2 feet (24 in) from bottom of infiltrating practices/BMPs; 4 feet is recommended for bioretention and permeable pavement performance. Bioretention counts up to 12-inch surface ponding toward VR; pipeless bioretention requires design infiltration ≥0.50 in/hr (measured ≥1.0 in/hr). Underdrains required when measured in-situ infiltration <1.0 in/hr (design <0.5 in/hr). Permeable aggregate storage has separate minimum depths (4 in pedestrian, 8 in vehicle). Excerpts lack green-roof chapter detail and named MTD verification programs (TAPE/NJCAT).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dover-de", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dover-de/", "data_url": "https://stormwateratlas.com/data/manuals/dover-de.json", "document_metadata": { "jurisdiction_name": "City of Dover", "jurisdiction_level": "municipality", "state_code": "DE", "document_title": "Delaware Sediment and Stormwater / Wet Pond Standards (capital MS4 partial)", "version_or_edition": "Section 13.0 Wet Ponds (DRAFT public-notice revision)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "DNREC Sediment and Stormwater Program framework. Wet ED Ponds receive RPv credit via 48-hour extended detention of the Resource Protection Volume (RPv); exact RPv depth defined in Delaware Sediment and Stormwater Regulations. Capital MS4 follows statewide standards; full technical document PDF often unavailable via direct download.", "peak_flow_calculation_method": [ "Site-adjusted runoff curve number (RCN)", "Cv / Fv quantity management per DNREC regulations" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Quantity Management Pond", "Wet Extended Detention (ED) Pond", "Other DNREC-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Dover capital MS4 follows DNREC Sediment and Stormwater standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "48-hour extended detention of the Resource Protection Volume (RPv)", "page_or_section": "Wet Ponds §13" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The drain pipe should have an upturned elbow or protected intake within the Wet Pond to help keep it clear of sediment deposition, and a diameter capable of draining the Wet Pond within 24 hours.", "page_or_section": "13.6 Wet Pond Design Criteria, page 14" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "If the infiltration test results in an infiltration rate greater than 1.0 inch/hour at the proposed Wet Pond invert, and the seasonal high groundwater table is two feet or more below the proposed Wet Pond invert, a stormwater management BMP other than a Wet Pond or Wet ED Pond should be designed.", "page_or_section": "13.3 Wet Pond Feasibility Criteria, page 8" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "INF = Monthly infiltration loss (assume 7.2 @ 0.01 inch/hour)", "page_or_section": "13.6 Wet Pond Design Criteria, Equation 13.1, page 11" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent Pool Depth: The minimum depth to prevent the permanent pool area from being overtaken by undesirable vegetation is 4 feet.", "page_or_section": "13.6 Wet Pond Design Criteria, page 12" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "For RPv compliance, a Wet ED Pond must provide 48 hours extended detention for the RPv runoff volume.", "page_or_section": "13.2 Wet Pond Practice Summary, page 5" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The forebay should have a length to width ratio of 2:1 or greater.", "page_or_section": "13.5 Wet Pond Pretreatment Criteria, page 10" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Wet ED Ponds that provide 48-hour detention receive full credit for the portion of the RPv managed", "page_or_section": "13.1 Wet Pond Credit Calculations, page 3" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum depth = 4'; maximum depth = 8'", "page_or_section": "13.2 Wet Pond Practice Summary, Section 13.6 Geometry, page 5" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Partial coverage via wet-pond chapter only — prefer full Delaware Technical Document when a stable public PDF is available.", "fields_not_found": [] }, "source": { "document_url": "https://documents.dnrec.delaware.gov/Admin/Public-Notices/WSS20260001/13-0-Wet-Ponds-DRAFT-strikethrough.pdf", "landing_page_url": "https://dnrec.delaware.gov/watershed-stewardship/sediment-stormwater/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "dover-de.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "wet_pond" ], "enriched_at": "2026-08-13T08:07:37.577Z", "enrich_model": "composer-2.5:run-719399a0-0d30-4d35-b3e2-cb0f0b030dc3", "enrich_notes": "Chapter 13 covers Wet Quantity Management Ponds and Wet Extended Detention (ED) Ponds only. RPv depth is not stated in these excerpts (referenced to Delaware Sediment and Stormwater Regulations). Wet ED Ponds require 48-hour extended detention of RPv for credit. Permanent pool minimum 4 ft and maximum 8 ft; water balance uses 24-inch reservoir and 0.01 in/hr infiltration assumption. Forebay length-to-width ratio ≥2:1; pond flow-path length ratio minimum 2:1. Seasonal high groundwater two feet or more below invert cited for HSG A/B infiltration suitability.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "duluth-mn", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/duluth-mn/", "data_url": "https://stormwateratlas.com/data/manuals/duluth-mn.json", "document_metadata": { "jurisdiction_name": "City of Duluth", "jurisdiction_level": "municipality", "state_code": "MN", "document_title": "Minnesota Stormwater Manual (city MS4)", "version_or_edition": "Version 2.0, 2008", "adoption_or_effective_date": "2008", "last_revised_date": "2008", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Minnesota Stormwater Manual post-construction BMP sizing / volume control framework (city engineering guidelines PDF not found).", "peak_flow_calculation_method": [ "Minnesota Stormwater Manual methods" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration / filtration BMPs", "Detention / retention", "Other Minnesota Stormwater Manual practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Duluth MS4 follows Minnesota Stormwater Manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "48 hours is the REQUIRED maximum tf for bioretention under the CGP", "page_or_section": "Chapter 12-6 bioretention, page 397" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "infiltration devices that drain effectively in 48 hours", "page_or_section": "Chapter 6, page 164" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "requires a minimum distance of three feet between the bottom of an infiltrating BMP and the seasonally saturated water table", "page_or_section": "Chapter 7, page 174" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of 3 feet of separation between the bottom of the bioretention practice and seasonally saturated soils (or from bedrock) is REQUIRED", "page_or_section": "Chapter 12-6 bioretention, page 397" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the recommended depth of the prepared soil is 30 inches", "page_or_section": "Chapter 12-6 bioretention, page 388" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Facility filter media depth must be at least 2.5 feet deep", "page_or_section": "Chapter 12 bioretention variants, page 375" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "It is REQUIRED that permanent pool depths be a minimum of three feet and maximum of 10 feet at the deepest points", "page_or_section": "Chapter 12-9 Stormwater Ponds, page 470" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "It is HIGHLY RECOMMENDED that the Vcp be released over a minimum 24 hour period", "page_or_section": "Chapter 12-9 Stormwater Ponds, page 470" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Vwq equals 0.5 or 1.0 inch of runoff per impervious acre, depending on the receiving stream designation", "page_or_section": "Chapter 12-9 Stormwater Ponds, page 470" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Minnesota Stormwater Manual.", "fields_not_found": [] }, "source": { "document_url": "https://stormwater.pca.state.mn.us/sites/stormwater/files/Minnesota_Stormwater_Manual.pdf", "landing_page_url": "https://stormwater.pca.state.mn.us/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "duluth-mn.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:08:18.460Z", "enrich_model": "composer-2.5:run-12228bf4-da4e-41c9-b8e6-d0e39d55ede1", "enrich_notes": "Minnesota manual (Duluth MS4 context): WQV sizing explicitly 0.5 or 1.0 inch runoff per impervious acre by receiving stream (not a single value). CGP/bioretention requires filter bed drain within 48 hours; 3 ft SHWT separation for infiltrating BMPs; bioretention filter media 30 in recommended (2.5 ft minimum for infiltration/recharge variant). Pond permanent pool min depth 3 ft, max 10 ft; Vcp release over minimum 24 hours. Preferred in-situ infiltration ≥1 in/hr for recharge bioretention; infiltration trench soils ≥0.2 in/hr in Table 7.8.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "durham-nc", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/durham-nc/", "data_url": "https://stormwateratlas.com/data/manuals/durham-nc.json", "document_metadata": { "jurisdiction_name": "City of Durham", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "Reference Guide for Development", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Stormwater quality and quantity facility design per Sections 8.x. SCM design standards in Section 8.3 plus City addendum to NC DEQ archived Stormwater BMP/Design Manual. BMPs include bioretention, vegetated water quality swales, sand filters with underground detention.", "peak_flow_calculation_method": [ "Drainage criteria Section 8.1 / storm drainage, culverts, open channels, gutter spread", "100-year storm flooding check for habitable structures", "Peak flow calculations for stormwater quantity facilities" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Vegetated water quality swales", "Underground detention", "Closed sand filter with underground detention", "Silva Cell suspended pavement with bioretention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Durham Public Works Department", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Durham", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "North Carolina", "page_or_section": "NC DEQ references" }, { "field": "document_metadata.document_title", "excerpt": "Reference Guide for Development", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "NC DEQ Archived Stormwater Design Manual", "page_or_section": "Stormwater review criteria" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "habitable structure will be flooded or have water impounded against it during the 100-year storm event", "page_or_section": "Drainage criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "design of stormwater quality and/or quantity facilities", "page_or_section": "Stormwater Services role" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Storm Drainage / Culverts / Open Channels", "page_or_section": "Section 8.0" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Areas / Vegetated Water Quality Swales", "page_or_section": "SCM list" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "draw down the runoff from the first inch of rainfall (minimum) in a manner consistent with that specified in the approved construction drawings", "page_or_section": "Field Checklist Open/Closed Sand Filters, pages 186-187 / 193" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the structure is located at least one foot above the seasonal high water table.", "page_or_section": "Field Checklist for Open Sand Filters, page 186 (also Closed Sand Filter, page 193)" }, { "field": "practice_mentions.bioretention", "excerpt": "Infiltration SCMs include bioretention cells, sand filters that are open on the bottom, permeable pavement", "page_or_section": "8.1.5 Potential SCM Location Issues, page 140" }, { "field": "practice_mentions.sand_filter", "excerpt": "For sand filters: cleaned, washed, coarse concrete sand such as ASTM C33. The sand particles shall be less than 2 mm average diameter.", "page_or_section": "Materials Certification for SCMs with Filter Media, page 175" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Durham RGD; pair with City addendum to NC DEQ BMP manual for full SCM sizing.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.durhamnc.gov/DocumentCenter/View/3331/Reference-Guide-for-Development-", "landing_page_url": "https://www.durhamnc.gov/895/Stormwater-Development-Review", "retrieved_at": "2026-08-10T08:08:51.648Z", "original_filename": "durham-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:08:44.872Z", "enrich_model": "composer-2.5:run-081328fb-8430-46f8-a5a2-84a1e0eef28c", "enrich_notes": "Durham SCM design follows the archived NC DEQ Stormwater BMP Manual (2009–2016) plus the City Addendum (Section 8.3); excerpts here are mostly submittal/checklist/certification text, not full sizing standards. SHWT evaluation must follow NC DEQ Manual Chapter A-3; filtration SCMs need minimum vertical separation from SHWT (sand filter checklist: 1 ft). Bioretention/Silva Cell media certification requires in-situ infiltration 1–6 in/hr (verification, not a single stated design rate). Underground detention requires a 24-hour watertightness test (construction QA, not drawdown design time).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "el-paso-tx", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/el-paso-tx/", "data_url": "https://stormwateratlas.com/data/manuals/el-paso-tx.json", "document_metadata": { "jurisdiction_name": "City of El Paso", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Stormwater Design Manual", "version_or_edition": "2022", "adoption_or_effective_date": null, "last_revised_date": "2022", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 50, 100 ], "water_quality_volume_method": "Bioretention and other water quality BMPs addressed in Section 14; Atlas 14 rainfall used for hydrologic design.", "peak_flow_calculation_method": [ "Rational Method", "HEC-HMS for larger watersheds", "Streets / storm drains / channels / culverts commonly designed for 100-year (also 50-year street criteria)" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [ "Bioretention", "Detention", "Storm drains", "Channels", "Culverts" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of El Paso Stormwater Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of El Paso", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Stormwater Design Manual", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "(on roadways of four lanes or more) 100-year Within curb height (maximum curb h=1½” below top of curb and 50 cfs max) Streets (Local Streets) 50-year One lane high and dry 100-year Within curb height (maximum curb h= 1½” below top of curb and 50 cfs max) Storm Drain System 10", "page_or_section": "p. 12" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "bioretention", "page_or_section": "Section 14" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational Method / HEC-HMS", "page_or_section": "Hydrology" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention", "page_or_section": "Section 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All storm water storage shall drain within 72 hours through infiltration, gravity outlet, or mechanical means.", "page_or_section": "SECTION 2, General Design Notes item 9, page 13" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The pond must drain down within 72 hours, either by infiltration or by means of an outlet.", "page_or_section": "9.6 DRAIN TIME, page 45" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The lowest elevation of a basin cannot be less than 2 feet above the highest elevation of the ground water table.", "page_or_section": "General Design Notes item 18, page 14-15" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The pond must drain down within 72 hours, either by infiltration or by means of an outlet.", "page_or_section": "9.6 DRAIN TIME, page 45" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention basins are designed to infiltrate collected water within 24 hours.", "page_or_section": "14.2.4 Bioretention Basin Design, page 63" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "El Paso SWDM 2022; Atlas 14 + Rational/HEC-HMS. Confirm exact street vs major conveyance return periods from tables. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.elpasotexas.gov/assets/Documents/CoEP/Planning-and-Inspections/Planning-Divisions/Combined-Storm-Water-Design-Manual.pdf", "landing_page_url": "https://www.elpasotexas.gov/", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "el-paso-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T08:09:13.093Z", "enrich_model": "composer-2.5:run-801f26c8-b19f-4139-9db4-f1853e330685", "enrich_notes": "El Paso SWDM May 2022 draft emphasizes quantity (100-year 24-hr retention with 30% safety factor; HEC-HMS routing). Section 14 sizes bioretention for ~0.5–1 in storm from impervious area (goal, not fixed WQv). Basin PI shall not exceed 8; infiltration not used for retention pond volume sizing. Drywells prohibited.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "elizabeth-nj", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/elizabeth-nj/", "data_url": "https://stormwateratlas.com/data/manuals/elizabeth-nj.json", "document_metadata": { "jurisdiction_name": "City of Elizabeth", "jurisdiction_level": "municipality", "state_code": "NJ", "document_title": "New Jersey Stormwater BMP Manual / N.J.A.C. 7:8 (city MS4 follows NJDEP standards)", "version_or_edition": "Chapter 5: July 2023; Chapter 9.7: January 2026", "adoption_or_effective_date": "2023-07", "last_revised_date": "2026-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5). NRCS methodology computes WQDS runoff volume, peak rate, and hydrograph; BMPs such as small-scale bioretention must store/treat the entire WQDS volume.", "peak_flow_calculation_method": [ "USDA NRCS methodology (NRCS Runoff Equation and Dimensionless Unit Hydrograph)", "NRCS Curve Number (CN) method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Small-scale green infrastructure BMPs", "Small-scale bioretention systems", "Small-scale infiltration basins", "Green roofs", "Pervious paving systems", "Grass swales", "Cisterns", "Green Infrastructure MTDs / MTDs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Elizabeth MS4 follows NJDEP Stormwater BMP Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — NJDEP BMP Manual / N.J.A.C. 7:8", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQDS: 1.25 inches of rain falling nonuniformly over 2 hours", "page_or_section": "N.J.A.C. 7:8-5.5 / Ch.5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The capacity of the underdrain must be sufficient to allow the system to drain within 72 hours", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7: Small-Scale Bioretention Systems (Page 74 / c0092)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the bioretention system fails to drain the Water Quality Design Storm within 72 hours, corrective action must be taken", "page_or_section": "Chapter 9.7: Small-Scale Bioretention Systems, Maintenance (Page 49 / c0117)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the minimum depth of 18 inches may not be sufficient", "page_or_section": "Chapter 9.7, Stormwater Tree Pit (Page 22 / c0097)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "In sloped-bottom systems, the maximum longitudinal slope is 10%.", "page_or_section": "Chapter 9.7, Bioretention Swale (Page 22 / c0097)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table (SHWT) must be at least 1 foot below the bottom of the gravel layer.", "page_or_section": "Chapter 9.7, underdrain requirements (Page 74 / c0092)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "which is greater than the 2 ft minimum separation requirement.", "page_or_section": "Chapter 9.7, Example 3 Step 4 (Page 34 / c0105)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "the water depth above the soil bed should not exceed the maximum design depth of 12 inches", "page_or_section": "Chapter 9.7, Example 1 (Page 23 / c0099)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "For the WQDS, the maximum depth of runoff is 18 inches at the down-gradient end of a sloped-bottom system", "page_or_section": "Chapter 9.7, Bioretention Swale (Page 22 / c0097)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NJDEP Stormwater BMP Manual / N.J.A.C. 7:8.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dep.nj.gov/wp-content/uploads/stormwater/bmp/njswbmp-chapter-9.7-small-scale-bioretention-systems-january-2026.pdf", "landing_page_url": "https://dep.nj.gov/stormwater/stormwater-management/bmp-manual/", "retrieved_at": "2026-08-10T09:45:18.912Z", "original_filename": "elizabeth-nj.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 10, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "swale" ], "enriched_at": "2026-08-13T08:10:06.086Z", "enrich_model": "composer-2.5:run-c6e55858-e0c7-4b59-8188-3ff83926a6d7", "enrich_notes": "WQDS is referenced throughout for sizing but the 1.25-inch WQDS rainfall depth is not stated in these excerpts. SHWT separation is explicitly 1 ft below the gravel layer (underdrain bioretention) and 2 ft minimum between basin/soil-bed bottom and SHWT in infiltration examples—single canonical value not unified here. Surface ponding limits include 12 in max above soil bed (planter boxes) and 18 in max runoff depth at the down-gradient end of sloped bioretention swales for WQDS. Underdrain bioretention must drain within 72 hr (24 hr where subject to pedestrian traffic). Example recharge/design rates (e.g., 1, 1.1, 1.5 in/hr) are site-specific, often half tested Ksat.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "erie-pa", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/erie-pa/", "data_url": "https://stormwateratlas.com/data/manuals/erie-pa.json", "document_metadata": { "jurisdiction_name": "City of Erie", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual / Act 167", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "PA PCSM Manual pollutant-load approach coupling volume and water quality management; Act 167 / MS4 ordinances require BMPs consistent with Pennsylvania Stormwater BMP / PCSM Manual.", "peak_flow_calculation_method": [ "PA PCSM / Stormwater BMP Manual methods", "Act 167 stormwater management ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Volume-reducing SCMs", "Water quality SCMs", "Post-construction BMPs per PA Manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Erie MS4 / Act 167 cites PA PCSM Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DRAFT / Page 1-3 1.1 OVERVIEW OF PCSM MANUAL This PCSM Manual establishes DEP-approved procedures for conducting PCSM stormwater analyses and provides SCM standards that can be used for regulatory compliance under Chapter 102. These procedures and standards may be applied to he", "page_or_section": "p. 12" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / page B-31" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance Above SHWT 2 ft ... (multiple infiltration and bioretention SCM columns)", "page_or_section": "Table 3-90 / page 3-310" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil media depth should be at least 18 inches.", "page_or_section": "Section 3.4.6 Vegetated Conveyance / page 3-96" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil Media Depth Min. 18 in ... 3.5.1 Bioinfiltration; 3.6.1 Bioretention; 3.7.1 MRC Bioretention", "page_or_section": "Table 3-90 / page 3-310" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum Ponding/Storage Depth ... 3.5.1 Bioinfiltration 2 ft; 3.6.1 Bioretention 2 ft", "page_or_section": "Table 3-90 / page 3-310" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Section 3.5.4 Infiltration Trench / page 3-135" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Section 3.5.5 Underground Infiltration Basin / page 3-146" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Section 3.8.1 Wet Basin / page 3-286" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio should be at least two to one.", "page_or_section": "Section 3.6.6 Engineered Stormwater Treatment Wetland / page 3-205" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The length to width ratio of the basin should be a minimum of 2:1 to avoid short circuiting.", "page_or_section": "Section 3.8.1 Wet Basin / page 3-286" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Soil Media Depth Min. ... 3.6.2 Green Roof Min. 3 in", "page_or_section": "Table 3-90 / page 3-310" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via PA PCSM Manual (Allentown/Harrisburg pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_parameters.shwt_separation_inches" ] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "erie-pa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:10:46.211Z", "enrich_model": "composer-2.5:run-f7c471c0-046f-4c24-b9c0-912abbe9a885", "enrich_notes": "PA PCSM (Erie via state manual): general infiltration SCMs require 2 ft (24 in) separation from SHWT/limiting zone (Appendix B.8; Table 3-90). Bioinfiltration/bioretention/MRC bioretention and vegetated conveyance share min 18 in filter media; Table 3-90 lists max ponding 2 ft (24 in) for bioinfiltration and bioretention. Infiltration trench and underground infiltration drawdown to native soil limited to 72 hr. Wet basin permanent pool min 5 ft (60 in) from 1.2-inch/2-hour runoff volume sizing; temporary pool drawdown within 3 days. Engineered treatment wetland and wet basin length:width min 2:1. Green roof min growing media 3 in (Table 3-90). Site infiltration classification uses 0.25 and 0.4 in/hr thresholds (not a single design infiltration rate). Swale bottom width given as 2–8 ft range only. No named MTD verification program (TAPE/NJCAT) in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "eugene-or", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/eugene-or/", "data_url": "https://stormwateratlas.com/data/manuals/eugene-or.json", "document_metadata": { "jurisdiction_name": "City of Eugene", "jurisdiction_level": "municipality", "state_code": "OR", "document_title": "Stormwater Management Manual", "version_or_edition": "2025", "adoption_or_effective_date": "2025-07-01", "last_revised_date": "2025-01-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Implements Eugene Code 9.6790–9.6797 standards for flood control, stormwater quality (pollution reduction facilities sized to Water Quality Design Storm), oil control for high-risk vehicle areas, and flow control. Facility selection/design in Chapters 2–3; flood control design storm tables in Appendix K; water quality design storm development in Appendix L.", "peak_flow_calculation_method": [ "Flood control design methodologies (on-site / off-site facilities)", "Flow control methodologies", "Water quality facility selection and design", "Underground Injection Control (UIC) constraints where applicable" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater quality / pollution reduction facilities", "Flow control facilities", "Flood control facilities", "Oil control facilities", "Infiltration / UIC facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Eugene / STORMWATER MANAGEMENT IN EUGENE", "page_or_section": "Chapter 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Eugene", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Oregon / Eugene Code", "page_or_section": "1.1" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Eugene Code as in effect on July 1, 2025", "page_or_section": "Appendix A / intro" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Eugene Code 9.6790 Stormwater Development Standards", "page_or_section": "1.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "STORMWATER QUALITY / Water Quality Design Storm", "page_or_section": "1.7 / Appendix L" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "STORMWATER FLOOD CONTROL / FLOW CONTROL", "page_or_section": "1.6 / 1.9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater quality / oil control / flow control / flood control facilities", "page_or_section": "Chapter 1 TOC" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "When sized for flood control, infiltration facilities must infiltrate the Flood Control Design Storm Event within 30 hours.", "page_or_section": "2.2.2 Infiltration Facilities, page 34" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The required drawdown time for Drywells is 30 hours.", "page_or_section": "2.3.16 Drywell Design Requirements, page 72" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The required drawdown time for Soakage Trenches is 30 hours.", "page_or_section": "2.3.17 Soakage Trench, page 74" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the Drywell shall be at least 5 feet above the seasonal high groundwater table unless DEQ-approved pretreatment is provided.", "page_or_section": "2.3.16 Drywell, page 73" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the Soakage Trench drain rock layer shall be no less than 5 feet above seasonally high groundwater unless DEQ-approved pretreatment is provided.", "page_or_section": "2.3.17 Soakage Trench, page 75" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "A maximum infiltration rate of 2.5 inches per hour shall be allowed for design of extended filtration facilities based on the assumed infiltration rate through the growing medium.", "page_or_section": "2.4.2 Presumptive Approach, page 77" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The maximum depth of the pond shall not exceed 4 feet.", "page_or_section": "2.3.8 Ponds Design Requirements, page 51" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum length-to-width ratio is 3:1, at the maximum water surface elevation.", "page_or_section": "2.3.8 Ponds Design Requirements, page 51" }, { "field": "practice_mentions.swale", "excerpt": "Flow-rate-based facility design: Swales, filter strips, oil/water separators, and proprietary treatment systems shall be sized to treat a rate of flow draining through them.", "page_or_section": "1.7.2, page 20" }, { "field": "practice_mentions.bioretention", "excerpt": "Combination Flow-Rate-Volume-Based Facility: A stormwater management facility such as a rain garden, planter, sand filter, soakage trench or drywell", "page_or_section": "1.4 DEFINITIONS, page 7" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Contained Planters, Eco roofs, Permeable Pavements, and Tree Credits are impervious area reduction techniques.", "page_or_section": "2.2.1, page 34" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Mechanical treatment facilities, if utilized must be selected from the list of approved proprietary treatment technologies", "page_or_section": "2.2.4, page 34" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Eugene 2025 SWMM with appendices. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.eugene-or.gov/DocumentCenter/View/79289/2025-Stormwater-Management-Manual-with-Appendices", "landing_page_url": "https://www.eugene-or.gov/477/Stormwater-Management-Manual", "retrieved_at": "2026-08-10T09:06:14.926Z", "original_filename": "eugene-or.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 30, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:11:04.418Z", "enrich_model": "composer-2.5:run-6475e387-122b-4624-a36f-8a2ef8919a82", "enrich_notes": "Water quality sizing uses Water Quality Design Storm (Appendix L referenced, not in excerpts); permanent pool volume = 2× WQ design storm runoff volume. Infiltration suitability thresholds: <2 in/hr, bedrock <5 ft, groundwater <6 ft below surface, slope >10%. NRCS A/B presumed ≥2 in/hr; C/D <2 in/hr. Drywell/soakage minimum measured rate 0.5 in/hr; optimal >2 in/hr. Swale O&M expects drain within 48 hours after storm (maintenance criterion, separate from 30 hr flood-control drawdown for infiltration/drywell/soakage). Soakage trench drain rock layer minimum 12 in deep; trench minimum width 12 in.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "evansville-in", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/evansville-in/", "data_url": "https://stormwateratlas.com/data/manuals/evansville-in.json", "document_metadata": { "jurisdiction_name": "City of Evansville", "jurisdiction_level": "municipality", "state_code": "IN", "document_title": "Indiana Storm Water Quality Manual (EMC 16.20 / IDEM reference)", "version_or_edition": "October 2007", "adoption_or_effective_date": "2007-10-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Treat at least one-half inch of storm water runoff (water quality volume or storage) from impervious surfaces, targeting ≥80% TSS removal on an annual average basis; post-development peak discharge rates and volumes should not exceed predevelopment levels (Indiana Storm Water Quality Manual / IDEM).", "peak_flow_calculation_method": [ "Rational Method", "NRCS TR-55", "NRCS TR-20" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Swales", "Filter Strip / Filter Ridge", "Riparian Buffer Zones", "Sand Filters", "Pervious Concrete / Porous Asphalt / Porous Pavers", "Infiltration Trench / Basin", "Bioretention Systems", "Dry Extended Detention / Wet Detention", "Constructed Storm Water Wetlands", "Subsurface Detention/Retention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Evansville Municipal Code Title 16 Drainage cites Indiana Storm Water Quality Manual", "page_or_section": "Coverage note / EMC 16.20" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat at least one-half inch of storm water runoff (water quality volume or storage) from impervious surfaces", "page_or_section": "Indiana Storm Water Quality Manual" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — IDEM / Indiana SWQ Manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume (WQV). The volume of runoff generated by one inch of rainfall on a site.", "page_or_section": "Appendix A — Glossary of Terms, page 734" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Runoff Capture Volume (RCV). The runoff capture volume is equivalent to the water quality volume (WQV) and is the storm water runoff volume generated by the first inch of rainfall on the site.", "page_or_section": "Appendix A — Glossary of Terms, page 731" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The pond should contain a low-flow drain with an adjustable gate valve allowing for gradual discharge. Recommended drawdown is 24 hours.", "page_or_section": "Chapter 8, Wet Detention Ponds, Table 3, page 639" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the bioretention area should be three feet or more above the seasonal high water table", "page_or_section": "Chapter 8, Bioretention Systems, page 619" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Water table Bottom of the basin > 3 feet above the seasonal high water table depth", "page_or_section": "Chapter 8, Infiltration Basin, Table 2, page 609" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the reservoir should be a minimum of three feet above any limiting layer (e.g., seasonal high water table, glacial till, bedrock).", "page_or_section": "Chapter 8, Porous Asphalt Systems, page 577" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A separation depth of three feet or more is usually sufficient.", "page_or_section": "Chapter 8, Wet Detention Ponds, page 636" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Sand/Gravel Substrate Aeration and drainage for planting bed is provided by a 12 to 20- inch deep sand and/or gravel bed.", "page_or_section": "Chapter 8, Bioretention Systems, Table 2, page 620" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Minimum dimensions for a bioretention area are 10 feet wide by 20 feet long. Any system wider than 20 feet should be at least twice as long to evenly distribute the flow.", "page_or_section": "Chapter 8, Bioretention Systems, page 619" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "A ponding depth of six to nine inches is recommended.", "page_or_section": "Chapter 8, Bioretention Systems, page 619" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water is retained during storm events and released into the permanent pool over 12 to 48 hours.", "page_or_section": "Chapter 8, Wet Detention Ponds, Table 4, page 640" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Shallow Marsh. The portion of a storm water wetland that consists of aquatic vegetation within a permanent pool ranging in depth from 6 inches to 18 inches during normal conditions.", "page_or_section": "Appendix A — Glossary of Terms, page 731" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Indiana Storm Water Quality Manual referenced by Evansville drainage code; local EMC may add site-specific criteria.", "fields_not_found": [] }, "source": { "document_url": "https://www.inafsm.net/assets/docs/indiana%20storm%20water%20quality%20manual.pdf", "landing_page_url": "https://www.codepublishing.com/IN/Evansville/html/Evansville16/Evansville1620.html", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "evansville-in.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:11:24.224Z", "enrich_model": "composer-2.5:run-a83e6d07-3e98-4981-b36f-d780c10ced13", "enrich_notes": "Manual glossary defines WQV as runoff from one inch of rainfall; BMP sections often size treatment for small storms described as typically 0.5 to 1.5 inches (reservoir/first-flush language). SHWT separation of three feet appears consistently for infiltration, bioretention, wet ponds, wetlands, and porous pavement reservoirs. Bioretention ponding is recommended as six to nine inches (range, not a single design depth). Wet extended detention variant cites release over 12 to 48 hours; dry extended detention excerpt in corpus has no explicit drain time.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "everett-wa", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/everett-wa/", "data_url": "https://stormwateratlas.com/data/manuals/everett-wa.json", "document_metadata": { "jurisdiction_name": "City of Everett", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Management Manual for Western Washington (Ecology 2024; city MS4)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "Adopts Ecology Stormwater Management Manual for Western Washington (SWMMWW) Minimum Requirements including runoff treatment and flow control. Local drainage manuals/ordinances typically supplement SWMMWW for city conditions; continuous simulation (WWHM/HSPF) sizes flow control.", "peak_flow_calculation_method": [ "Continuous Simulation Models", "WWHM / HSPF", "Single Event Hydrograph Method", "SBUH / SCS / NRCS methods (as allowed)" ], "required_hydrologic_hydraulic_software": [ "WWHM", "HSPF" ], "approved_bmp_categories": [ "Flow Control BMPs", "Runoff Treatment BMPs", "LID BMPs", "Source Control BMPs", "Infiltration / bioretention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Everett MS4 follows Ecology SWMMWW", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — Ecology SWMMWW 2024", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Document that the maximum ponded depth from the infiltration BMP can infiltrate through the infiltration BMP surface within 48 hours.", "page_or_section": "Volume V - Chapter 5 - Page 823" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "In most cases, UIC wells are designed to completely drain ponded runoff within 48 to 72 hours after flow to the UIC well has stopped.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of BMP T7.10: Infiltration Ponds or BMP T7.20: Infiltration Trenches shall be ≥ 5 feet above the seasonal high-water mark, bedrock (or hardpan) or other low permeability layer.", "page_or_section": "Volume V - Chapter 5 - Page 823" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A 5-foot separation between the bottom of the well and the top of the groundwater is required, unless a demonstrative approach confirms that a separation of 3 feet will meet the nonendangerment standard.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The \"Default\" and \"Custom\" BSM depth must be 18 inches to provide Runoff Treatment and good growing conditions for selected plants.", "page_or_section": "Volume V - Chapter 5 - Page 921" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Appropriate field testing indicates soils have a measured (a.k.a. initial) native soil saturated hydraulic conductivity (Ksat) less than 0.3 inches per hour.", "page_or_section": "Volume V - Chapter 5 - Page 835" }, { "field": "practice_mentions.bioretention", "excerpt": "runoff from these types of landscaped areas should be directed to bioretention, biofiltration, or constructed wetland BMPs prior to discharge to UIC wells.", "page_or_section": "Volume I - Chapter 4 - Page 171" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Ecology SWMMWW (Vancouver/Bellevue western WA pattern). Prefer city drainage manual if a durable public PDF is later found.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.cityofcamas.us/sites/default/files/fileattachments/community_development/page/9505/2024swmmww_6-14-24.pdf", "landing_page_url": "https://www.everettwa.gov/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "everett-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:12:10.259Z", "enrich_model": "composer-2.5:run-b6dcfcfc-48be-4641-81c6-b4787f7abfa9", "enrich_notes": "Corpus is SWMMWW (Ecology 2024) via Everett adoption; UIC drawdown cited as 48–72 hr while infiltration BMPs require 48 hr ponded drawdown. SHWT separation varies by BMP (e.g. 12 in permeable pavement gravel base, 36 in larger bioretention, 60 in general infiltration/UIC presumptive); 60 in reflects repeated 5 ft minimum above seasonal high groundwater for infiltration ponds/trenches and UIC. Native-soil thresholds include 0.3 in/hr infeasibility and long-term design up to 3 in/hr; BSM design Ksat 12 in/hr is bioretention-specific. Permeable pavement cites 6 in and 12 in sand treatment layers, not aggregate storage depth. Wet pond excerpt gives >8 ft as max depth concern, not permanent pool design depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fargo-nd", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/fargo-nd/", "data_url": "https://stormwateratlas.com/data/manuals/fargo-nd.json", "document_metadata": { "jurisdiction_name": "City of Fargo", "jurisdiction_level": "municipality", "state_code": "ND", "document_title": "Policy on Storm Water Discharge and Treatment Requirements (Storm Sewer Manual)", "version_or_edition": "2019-09-09", "adoption_or_effective_date": "2019-09-09", "last_revised_date": "2019-09-09", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Sites >3 acres: max discharge 1 cfs/acre; 1–3 acre sites per table. Post-development 2-, 10-, and 100-year peaks per NOAA Atlas 14 for Fargo. Water quality (Appendix C): wet detention Vwq = 1800 cu-ft per impervious acre; extended detention Vwqed = 1800 cu-ft; infiltration Vwq = 0.5 inches from impervious; manufactured devices treat first 0.5 inches from impervious.", "peak_flow_calculation_method": [ "NOAA Atlas 14 (Fargo) for 2-/10-/100-year storms", "Allowable release rate tables (Appendix B)", "Detention/retention pond design (Appendix D)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention ponds", "Extended detention", "Infiltration", "Manufactured treatment devices", "Regional or on-site detention/retention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Fargo Policy on Storm Water Discharge and Treatment Requirements", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Storm Water Discharge and Treatment Policy 2019", "page_or_section": "Header" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet Detention Ponds Water Quality Volume (Vwq) = 1800 cu-ft per impervious acre ... Infiltration Water Quality Volume (Vwq) = 0.5 inches from impervious area", "page_or_section": "Appendix C" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "post-development 2, 10, and 100-year storm events as identified under the most current NOAA Atlas 14", "page_or_section": "Policy / Appendix A" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Storm Water Discharge and Treatment Policy 2019 10 features. Flow-Through Treatment devices such as “Defenders ™” shall provide as a minimum 80 percent removal of sediment with a particle size distribution equivalent to the standard OK- 110 at a feed concentration of 300 mg/L", "page_or_section": "p. 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Infiltration Water Quality Volume (Vwq) = 0.5 inches from impervious area.", "page_or_section": "Appendix C, page 9" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Size devices to treat the first 0.5 inches of runoff from impervious area.", "page_or_section": "Appendix C, page 9" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry Detention Ponds (w/Extended Detention) Extended Detention / Water Quality Volume (Vwqed) = 1800 cu-ft per impervious acre draining to pond.", "page_or_section": "Appendix C, page 9" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet Detention Ponds Water Quality Volume (Vwq) = 1800 cu-ft per impervious acre draining to the pond.", "page_or_section": "Appendix C, page 9" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Flow-Through Treatment Devices Size devices to treat the first 0.5 inches of runoff from impervious area.", "page_or_section": "Appendix C, page 9" }, { "field": "practice_mentions.bioretention", "excerpt": "The volume captured in rain gardens, or passed through biofilters with under drains, would be grouped with infiltration for water quality treatment.", "page_or_section": "Appendix C, page 9" }, { "field": "practice_mentions.swale", "excerpt": "Construction of \"rain gardens\", \"grassy swales\", and other methods of achieving water quality are encouraged and will be evaluated on a case-by-case basis.", "page_or_section": "Appendix B, page 8" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "15-page policy/manual; compact but covers quantity + WQ appendices.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://download.fargond.gov/0/storm_sewer_manual_city_of_fargo_policy_2019-09-09.pdf", "landing_page_url": "https://download.fargond.gov/", "retrieved_at": "2026-08-10T09:45:18.892Z", "original_filename": "fargo-nd.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:13:24.568Z", "enrich_model": "composer-2.5:run-875dd375-fa54-4d97-b99b-6e4b5074d693", "enrich_notes": "Appendix C (MS4): wet detention Vwq = 1800 cu-ft per impervious acre with Vwq drawdown minimum 12 hours; extended detention Vwqed = 1800 cu-ft per impervious acre with drawdown minimum 24 hours and maximum 72 hours; infiltration Vwq = 0.5 in from impervious with discharge through soil/filter within 48 hours; flow-through devices sized for first 0.5 in from impervious. Appendix D regional wet pond minimum 15 acre-ft (avg bottom width 100 ft); dry pond 7.5 acre-ft (min bottom width 100 ft). Quantity: sites >3 ac limited to 1 cfs/ac; 1–3 ac per release-rate table.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fayetteville-ar", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/fayetteville-ar/", "data_url": "https://stormwateratlas.com/data/manuals/fayetteville-ar.json", "document_metadata": { "jurisdiction_name": "City of Fayetteville", "jurisdiction_level": "municipality", "state_code": "AR", "document_title": "NWA Stormwater BMP Manual (Fayetteville MS4 / Northwest Arkansas)", "version_or_edition": "Revised December 2016 / NWA 2016", "adoption_or_effective_date": "2016-12", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Northwest Arkansas regional Stormwater BMP Manual used by Fayetteville and peer NWA MS4s. Construction sediment traps and retention/detention sized to municipal design storms; LID Appendix B addresses rain gardens, bioretention, infiltration, and green roofs. No single regional WQv equation — follow host municipality + NWA manual.", "peak_flow_calculation_method": [ "Rational Method", "Hydrologic analysis (2-/10-/100-year peaks)", "Pre-developed allowable discharge methods" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Preserving Natural Vegetation / Buffer Zones", "Retention / detention ponds", "Bioretention / rain gardens", "Infiltration practices", "Construction ESC BMPs per NWA manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Fayetteville is an NWA MS4 using the regional Stormwater BMP Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "CONTROL Best Management Practices Manual Revised December 2016 Little Flock, AR Permit No. ARR040035 AFIN no. 88-00855", "page_or_section": "p. 1" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Retention ponds should be sized to hold the entire design storm of the municipality that they are located in", "page_or_section": "BMP 410, page lxxxiii (83)" }, { "field": "practice_mentions.bioretention", "excerpt": "Rain gardens are landscaped bio-retention facilities that soak up runoff displaced by the impervious area of a structure.", "page_or_section": "Appendix B, page xcviii (98)" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Rooftop is a layer of vegetation, shrubs, or trees planted on rooftops to absorb stormwater runoff.", "page_or_section": "Appendix B, page xcviii (98)" }, { "field": "practice_mentions.swale", "excerpt": "Bio-retention and grassed swales are common infiltration techniques.", "page_or_section": "Appendix B, page xcvii (97)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention ponds should also be designed to the standards of the municipality that they are located in", "page_or_section": "BMP 410, page lxxxiii (83)" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "One example of a de-watering BMP is a manufactured enclosed filter bag placed on a pervious pavement or material", "page_or_section": "BMP 420, page lxxxiii (83)" }, { "field": "practice_mentions.sand_filter", "excerpt": "In areas where local soils do not readily support infiltration, rain gardens can be modified to be underlain with a sand filtration system", "page_or_section": "Appendix B, page xcviii (98)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Provide an overflow lot utilizing grass or alternative pavers for peak demand parking.", "page_or_section": "Appendix B, page xcviii (98)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Northwest Arkansas regional BMP Manual.", "fields_not_found": [] }, "source": { "document_url": "https://cityoflittleflock.com/wp-content/uploads/2024/06/BMP-Manual-1-17-ALL.pdf", "landing_page_url": "https://www.bentonville.ar.gov/422/Stormwater-Management", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "fayetteville-ar.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:13:54.320Z", "enrich_model": "composer-2.5:run-89cc2cb6-54b6-4459-ab66-3f1b69df4ec7", "enrich_notes": "NWA 2016 manual excerpts are primarily construction ESC and planning; BMP 410 retention/detention sizing is deferred to the host municipality’s design storm, not a regional WQv depth. Appendix B describes rain gardens, bio-retention, infiltration, green rooftops, and sand filtration qualitatively (e.g., 10 ft setback from structures for rain gardens; green roof structural review if live load exceeds 17 psf) without minimum media, ponding, or drawdown numerics. Interceptor swale design tables (Table 8) are referenced in the TOC but not included in the corpus.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "flagstaff-az", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/flagstaff-az/", "data_url": "https://stormwateratlas.com/data/manuals/flagstaff-az.json", "document_metadata": { "jurisdiction_name": "City of Flagstaff", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Stormwater Management Design Manual", "version_or_edition": "2025", "adoption_or_effective_date": null, "last_revised_date": "2025", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Low Impact Development Runoff Capture Volume (ROCV): Impervious Surface Area (sq ft) × 1 inch = ROCV. ROCV requirement may be met by (1) retaining the minimum ROCV for ≥24 hours, (2) treating the discharge from the 2-year storm, or (3) a combination. Detailed LID design per City of Flagstaff LID Guidance Manual.", "peak_flow_calculation_method": [ "Rational Method / hydrograph methods per Ch.4 Hydrology", "On-site detention for developments >1/4 acre (policies in §5.3.8)", "2-year detention waived if site fully captures ROCV" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "LID / Runoff Capture Volume facilities", "Detention / multi-purpose basins", "Rainwater harvesting (passive/active)", "Bio-filters / infiltration", "Extended detention" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "2025 Stormwater Management Design Manual", "page_or_section": "Cover / §1.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Impervious Surface Area (square feet) X 1 inch = Runoff Capture Volume", "page_or_section": "§6.0 LID / ROCV" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "retaining the required minimum ROCV for a minimum of 24 hours, (2) treating the discharge from the 2-year storm", "page_or_section": "§6.2 policy 14" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Low Impact Development Runoff Capture Volume (ROCV): Impervious Surface Area (sq ft) × 1 inch = ROCV.", "page_or_section": "Atlas context (WQv method)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "ROCV requirement may be met by (1) retaining the minimum ROCV for ≥24 hours", "page_or_section": "Atlas context (WQv method)" }, { "field": "practice_mentions.extended_detention", "excerpt": "EXTENDED DETENTION – A basin designed for retention and detention. The retention portion of the basin is below the basin outlet that holds water and allows infiltration or has an underdrain system that filters water.", "page_or_section": "DEFINITIONS, page 8" }, { "field": "practice_mentions.swale", "excerpt": "The gutter flow from the street section must be conveyed into a receiving channel, roadside swale, or other approved means.", "page_or_section": "5.3.3.4 Curb and Gutter Terminations, page 37" }, { "field": "practice_mentions.bioretention", "excerpt": "The order of preference for open channels and swales shall be: 1. The use of natural bio-filters to promote infiltration and water quality treatment.", "page_or_section": "5.3.7.7 Channel Linings, page 61" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "RETENTION BASIN – is a stormwater storage facility which reduces runoff and is drained by subsurface infiltration or reuse instead of a positive outlet.", "page_or_section": "DEFINITIONS, page 10" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://www.flagstaff.az.gov/DocumentCenter/View/88520/2025-Stormwater-Management-Design-Manual", "landing_page_url": "https://www.flagstaff.az.gov/2131/Stormwater", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "flagstaff-az.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T08:18:56.025Z", "enrich_model": "composer-2.5:run-b3d983cd-3a94-4e8b-a67d-a396a01d83e8", "enrich_notes": "Corpus excerpts emphasize hydraulics, drainage reporting (ROCV/LID calculations referenced in drainage plans), and channel/swale preferences; BMP sizing and infiltration criteria are deferred to the City of Flagstaff LID Guidance Manual per atlas context. WQv is Runoff Capture Volume (ROCV): impervious area × 1 inch, with option to retain ROCV ≥24 hours, treat 2-year storm discharge, or combine.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "flint-mi", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/flint-mi/", "data_url": "https://stormwateratlas.com/data/manuals/flint-mi.json", "document_metadata": { "jurisdiction_name": "City of Flint", "jurisdiction_level": "municipality", "state_code": "MI", "document_title": "Lansing Stormwater Management Design Manual (EGLE WQv pattern)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 50, 100 ], "water_quality_volume_method": "No durable Flint design-manual PDF found. Using Lansing Stormwater Management Design Manual as Michigan EGLE MS4 pattern: water quality treatment volume from ~0.9 inches of rainfall; channel protection through 2-year 24-hour storm.", "peak_flow_calculation_method": [ "Water quality treatment volume (~0.9 in)", "Channel protection (2-year 24-hour)", "Collection system peak (10-/50-year)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater control measures (SCMs)", "Retention / infiltration", "Filtration / detention SCMs" ] }, "evidence": [ { "field": "design_parameters.max_drawdown_hours", "excerpt": "Storage facilities are to fully drain the surface water component within 48 hours following a storm event. The entire cross section should be drained within 72 hours.", "page_or_section": "ENGINEERING STANDARDS / Stormwater Storage, page 18" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Storage facilities are to fully drain the surface water component within 48 hours following a storm event.", "page_or_section": "ENGINEERING STANDARDS / Stormwater Storage, page 18" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Depth from bottom of facility to groundwater table … 2 foot minimum", "page_or_section": "Table 4 Infiltration Facility Design Criteria; Table 5 Detention Pond (Dry Pond, Constructed Wetland), pages 19–20" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil Permeability/Infiltration Rate … 0.5 inches/hr. minimum", "page_or_section": "Table 4 Infiltration Facility Design Criteria, page 19" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Maximum Depth … 1.5 feet wet depth without safety fencing", "page_or_section": "Table 5 Detention Pond Design Criteria (Wet Pond), page 20" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder using Lansing manual — replace with Flint city standards when found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://content.civicplus.com/api/assets/mi-lansing/5275ad94-2c28-4941-9d23-67842b45023f?cache=1800", "landing_page_url": "https://www.cityofflint.com/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "flint-mi.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 18, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:19:26.906Z", "enrich_model": "composer-2.5:run-41574a71-106c-4399-b22e-fea75654b878", "enrich_notes": "Corpus is Lansing Stormwater Design Manual (Flint proxy). WQv depth referenced via Table 1 but Table 1 not in excerpts. Infiltration swale bottom width given as 2–8 ft and bottom slope as 1%–6% (no single design number). Wet/constructed wetland max wet depth 1.5 ft applies without safety fencing; greater depths may be authorized with fencing. Channel protection cites 2-year 24-hour storm in infiltration narrative but no numeric WQv rainfall depth in provided pages.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fort-collins-co", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fort-collins-co/", "data_url": "https://stormwateratlas.com/data/manuals/fort-collins-co.json", "document_metadata": { "jurisdiction_name": "City of Fort Collins", "jurisdiction_level": "municipality", "state_code": "CO", "document_title": "Urban Storm Drainage Criteria Manual Volume 3 (MHFD/UDFCD) — regional Front Range reference", "version_or_edition": "November 2015 (Vol.3 Ch.1)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches of precipitation within the MHFD/UDFCD boundary (≈80th percentile storm); remaining runoff after volume reduction treated through capture and slow release of the WQCV. City drainage portals often HTML/403 — Front Range MS4s commonly apply USDCM Volume 3.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grass Buffers / Swales", "Bioretention", "Permeable Pavement", "Extended Detention Basins", "Sand Filters", "Constructed Wetland / Retention Ponds", "Underground / Source Control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Fort Collins Front Range MS4 — coverage via MHFD/UDFCD Volume 3 WQCV", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches", "page_or_section": "USDCM Vol.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Within the UDFCD boundary, the WQCV is based on runoff from 0.6 inches of precipitation.", "page_or_section": "Chapter 1, Common Stormwater Management Terms (page 11)" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention (rain gardens): The use of distributed on-site vegetated features such as rain gardens", "page_or_section": "Chapter 1, Step 1 (page 17)" }, { "field": "practice_mentions.wqv_depth_inches", "excerpt": "Water Quality Capture Volume (WQCV): This volume represents runoff from frequent storm events such as the 80th percentile storm.", "page_or_section": "Chapter 1 (page 11)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Regional MHFD criteria — prefer city-specific drainage criteria manual when a durable public PDF is available.", "fields_not_found": [] }, "source": { "document_url": "https://www.mhfd.org/files/7af5d4c2f/03_Chapter-1-Stormwater-Management.pdf", "landing_page_url": "https://www.fcgov.com/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "fort-collins-co.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:19:54.656Z", "enrich_model": "composer-2.5:run-56c6dffb-441d-4b28-839d-ba8dd2bff39a", "enrich_notes": "Corpus is USDCM Vol. 3 Chapter 1 (planning/regulatory). WQCV within UDFCD boundary is explicitly tied to 0.6 in precipitation (≈80th percentile); detailed BMP sizing is referenced in Chapters 3–5, not in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fort-wayne-in", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fort-wayne-in/", "data_url": "https://stormwateratlas.com/data/manuals/fort-wayne-in.json", "document_metadata": { "jurisdiction_name": "City of Fort Wayne", "jurisdiction_level": "municipality", "state_code": "IN", "document_title": "City Utilities Design Standards Manual", "version_or_edition": "July 2026", "adoption_or_effective_date": "2026-07", "last_revised_date": "2026-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "SW11 Stormwater Management: Water Quality Volume (WQv) sized via Reduced Runoff Method and/or Volume Based Method (SW11.06–SW11.07); documentation includes 2-year impacts. Acceptable stormwater quality BMPs include wet/dry extended detention, bioretention, constructed wetlands, proprietary water quality units, and treatment trains.", "peak_flow_calculation_method": [ "SW6.02 Design Storms — minor (10-year) and major (100-year) for storm sewers", "SW5 Hydrology methods (Rational / SCS / hydrographs)", "SW11.09 Stormwater Detention Calculations", "Compensatory storage and floodplain criteria (SW11.04)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet extended detention basins", "Dry extended detention basins", "Bioretention basins", "Constructed wetlands", "Underground detention", "Water quality swales", "Proprietary water quality units" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Fort Wayne", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City Utilities", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "City Utilities Design Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Utilities Design Standards", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minor (10-year) storm and the major (100-year) storm", "page_or_section": "SW6.02" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater Quality Volume The volume of runoff to be retained in a green infrastructure", "page_or_section": "Definitions / SW11" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "SW11.09 Stormwater Detention Calculations", "page_or_section": "SW11 TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wet Extended Detention Basins / Bioretention Basins / Constructed Wetlands", "page_or_section": "SW11.14–SW11.17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = Water quality storm, 1-inch rainfall", "page_or_section": "SW11.07 / page 200" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "prevent any of the runoff from the initial 1-inch rainfall from leaving the site", "page_or_section": "SW11.06 / page 199" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The draw-down time for the WQv must be 12 to 48 hours to meet the required stormwater quality imperative.", "page_or_section": "SW11.07 / page 200" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting soil bed depth ≥ 4 feet", "page_or_section": "Figure SW11.23 / page 223" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "stormwater to infiltrate through at least 18-inches of soil or media prior to entering the underdrain", "page_or_section": "SW11.16 / page 222" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max water quality pool depth: 6 inches. Typical ponding depth: 6-18 inches.", "page_or_section": "Figure SW11.23 / page 223" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate ≥ 0.5 inches/hr.", "page_or_section": "Figure SW11.23 Bioretention Engineered Planting Soil Mix / page 223" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Average Permanent Pool Depth: ≥ 4 ft", "page_or_section": "Figure SW11.18 Wet Extended Detention Basin / page 215" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Detention Time Approximately 48-hours for the water quality volume", "page_or_section": "Figure SW11.25 Constructed Wetlands / page 226" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Dimensions: Flat bottom (not V-bottom) 2' - 8' wide", "page_or_section": "Figure SW11.16 Water Quality Swale / page 212" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Longitudinal Slope: Max. 4%, 0% slope less than 25'", "page_or_section": "Figure SW11.16 / page 212" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Large July 2026 manual (text truncated); WQv numeric depth may be in SW11.07 tables not fully captured. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://utilities.cityoffortwayne.org/wp-content/uploads/2026/07/City-Utilities-Design-Standards-July-2026.pdf", "landing_page_url": "https://utilities.cityoffortwayne.org/contractors-engineers-developers/design-standards-manual", "retrieved_at": "2026-08-10T08:24:40.117Z", "original_filename": "fort-wayne-in.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 48, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": 48, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:20:17.038Z", "enrich_model": "composer-2.5:run-bf3735ec-ce0f-43db-b2f4-ee66fd72520c", "enrich_notes": "WQv uses P=1 inch (Reduced Runoff and Volume Based methods). WQv draw-down 12–48 hr (SW11.07). SHWT setback varies: 2 ft (many BMPs), 3 ft (water quality swale), 4 ft (permeable pavement, retention basin eligibility). Bioretention also requires ≥18 in soil/media infiltration path before underdrain for WQ credit; filter media infiltration ≥0.5 in/hr; dewatering 24–72 hr. Swale WQv ponding cap 12 in for 1 in WQv; soil infiltration >1 in/hr without underdrain. Proprietary units sized on 0.3 in rainfall SCS rate (SW11.08). Forebay length:width ≥3:1.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fort-worth-tx", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fort-worth-tx/", "data_url": "https://stormwateratlas.com/data/manuals/fort-worth-tx.json", "document_metadata": { "jurisdiction_name": "City of Fort Worth", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Stormwater Criteria Manual", "version_or_edition": "July 2024", "adoption_or_effective_date": "2024-07-15", "last_revised_date": "2024-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 5, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQV) Option 2: treat TSS for runoff from rainfalls up to 1.5 inches (85th percentile storm). Note: water quality protection is not currently required by the City but may be required by TRWD or other agencies. Manual incorporates NCTCOG iSWM Technical Manuals by reference.", "peak_flow_calculation_method": [ "Streambank Protection: on-site controlled release of 1-year, 24-hour storm over 24 hours (SPV) or downstream mitigation options", "Flood Mitigation: detention to completely mitigate increase in peak discharge; Adverse Impact Assessment / Zone of Influence", "Regulatory design storm: 1% annual chance (100-year) on ultimate development", "NCTCOG iSWM Technical Manual hydrologic methods by reference" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Dry detention pond", "Underground detention", "Integrated site design practices", "iSWM structural controls (by reference to NCTCOG Technical Manuals)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Fort Worth Stormwater Criteria Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Adoption of Manual by City of Fort Worth", "page_or_section": "Adoption" }, { "field": "document_metadata.state_code", "excerpt": "TPDES Stormwater permit", "page_or_section": "Design options table" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Criteria Manual", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "This Stormwater Criteria Manual (\"Manual\") is adopted and becomes effective on July 15, 2024.", "page_or_section": "Adoption" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The North Central Texas Council of Government (\"NCTCOG\") iSWM Technical Manuals are adopted and incorporated herein by reference.", "page_or_section": "Adoption" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "No increase greater than 0.1 feet in 1-, 5-, and 100-year flood elevations", "page_or_section": "Flood criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat the Water Quality Protection Volume (WQV) by reducing total suspended solids from the Development site for runoff resulting from rainfalls of up to 1.5 inches (85th percentile storm)", "page_or_section": "Design Options / Water Quality" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Provide on-site controlled release of the 1- year, 24-hour storm event over a period of 24 hours (Streambank Protection Volume, SPV)", "page_or_section": "Streambank Protection Option 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Dry Detention Pond / Underground Detention", "page_or_section": "Tables 3.22-3.23" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "3.5.3.1 Water Quality Protection Volume, page 49" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Option 2: Treat the Water Quality Protection Volume (WQV) by reducing total suspended solids from the Development site for runoff resulting from rainfalls of up to 1.5 inches (85th percentile storm)", "page_or_section": "Table 3.2, page 39" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.29 Soils, pages 118-119" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet Pond Limit maximum normal pool depth to about 4 ft (dugout)", "page_or_section": "Table 3.28 Physiographic Factors, page 117" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The release rate for both the WQv and SPv shall discharge the ED volume in a period of 24 hours or longer.", "page_or_section": "3.8.3.3 Outlet Structures, page 99" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Enhanced Swales ... Site Slope 4% max", "page_or_section": "Table 3.26 Site Applicability, page 113" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Fort Worth July 2024 SCM; WQ Option 2 is iSWM-aligned but City notes WQ not currently required by CFW itself. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.fortworthtexas.gov/files/assets/public/v/1/tpw/stormwater/documents/regulation-updates/july-2024-official-stormwater-criteria-manual.pdf", "landing_page_url": "https://www.fortworthtexas.gov/departments/tpw/stormwater/review", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "fort-worth-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:20:51.496Z", "enrich_model": "composer-2.5:run-a74afe15-fdb8-49d6-92eb-c01901f242e3", "enrich_notes": "City Stormwater Criteria Manual (July 2024) references NCTCOG iSWM Technical Manuals for WQV methods, site design, and Site Development Controls design criteria; water quality Option 2 is documented but not currently required by Fort Worth (TRWD or others may require). BMP numeric sizing beyond screening tables is largely by reference.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "frankfort-ky", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/frankfort-ky/", "data_url": "https://stormwateratlas.com/data/manuals/frankfort-ky.json", "document_metadata": { "jurisdiction_name": "City of Frankfort", "jurisdiction_level": "municipality", "state_code": "KY", "document_title": "LFUCG Stormwater Manual (KY urban post-construction reference for capital)", "version_or_edition": "2026 (effective May 1, 2026)", "adoption_or_effective_date": "2026-05-01", "last_revised_date": "2026-05-01", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "No durable Frankfort city design-manual PDF found. Using LFUCG Stormwater Manual as a Kentucky urban MS4 post-construction reference: WQv for new development — treat runoff from impervious areas for the 90th percentile storm of 1.2 inches; streambank protection via 24-hour detention of the 10-year 6-hour storm volume.", "peak_flow_calculation_method": [ "Post-construction water quantity and quality criteria", "Detention for 10-year and 100-year development levels" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure practices", "Extended detention basins", "Underground detention", "Post-construction BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Frankfort capital — coverage via LFUCG Stormwater Manual as KY urban reference (not a Frankfort-adopted document)", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "90th percentile storm of 1.2 inches", "page_or_section": "LFUCG Stormwater Manual" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The 90th percentile storm in Fayette County is 1.2 inches. The WQV is determined by multiplying 1.2 inches times the impervious area.", "page_or_section": "10.2.2 / page 138" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Multiply 1.2 inches times the total impervious area (rooftops, parking lots, sidewalks, and driveways)", "page_or_section": "1.7.3 / page 23" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain Time: Maximum drain time (i.e., ponding) is 24 hours.", "page_or_section": "10.3.2 Bioretention / page 140" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Provide a planting soil bed with a minimum width of 4 feet and a minimum depth of 4 feet (including a 12-inch sand bed).", "page_or_section": "10.3.2 Design Criteria / page 141" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Grade the top of the planting soil bed to provide a shallow ponding area with a maximum depth of 6 inches.", "page_or_section": "10.3.2 Design Criteria / page 141" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "An underdrain shall be provided if the underlying soils have an infiltration rate of less than 0.5 inches per hour.", "page_or_section": "10.3.2 / page 140" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration basins may be used in locations that have at least 5 feet of soil, with a permeability of at least 0.5 inches/hour underlying the device.", "page_or_section": "10.3.5 Design Criteria / page 149" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Design the extended detention outlet so that the \"design\" WQV requires a maximum of 24 hours to discharge.", "page_or_section": "10.6.2 / page 166" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Design the extended detention outlet so that a maximum of 24 hours would be required to release the design WQV.", "page_or_section": "10.9.2 / page 173" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Vegetated Roofs Soil area x soil depth x 0.18. Maximum soil depth for calculation purposes shall be 12 inches.", "page_or_section": "Table 1-7 / page 23" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder using Lexington-Fayette manual criteria — replace when Frankfort publishes a local drainage/stormwater design PDF.", "fields_not_found": [] }, "source": { "document_url": "https://content.lexingtonky.gov/sites/default/files/2026-04/LFUCG%20Stormwater%20Manual%2005.01.26.pdf", "landing_page_url": "https://www.lexingtonky.gov/government/departments-programs/environmental-quality-public-works/water-quality/municipal-separate-storm-sewer-system-ms4", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "frankfort-ky.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 48, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 12, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:21:28.369Z", "enrich_model": "composer-2.5:run-fb1be22c-599b-406e-abd1-ee52eeddd265", "enrich_notes": "Frankfort placeholder uses LFUCG (Lexington-Fayette) manual. WQV = 1.2 in × impervious area (90th percentile); runoff reduction credit 0.8 in × impervious. Underdrain required when native soil infiltration < 0.5 in/hr (most GI); tree trenches use < 2 in/hr. Bioretention planting bed min 4 ft depth (includes 12 in sand bed); ponding max 6 in; surface ponding drain max 24 h, full media drawdown max 3 days. Permeable pavement stone porosity 0.4; drain time per industry standard. Infiltration basins need ≥5 ft permeable soil at ≥0.5 in/hr above seasonal high water table (no numeric SHWT setback in inches). Wet pond L:W min 3:1; constructed wetland L:W min 2:1; bioretention L:W min 2:1 when width >10 ft.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "franklin-tn", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/franklin-tn/", "data_url": "https://stormwateratlas.com/data/manuals/franklin-tn.json", "document_metadata": { "jurisdiction_name": "City of Franklin", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Metro Nashville Stormwater Management Manual Volume 4 – BMPs (regional reference)", "version_or_edition": "2021", "adoption_or_effective_date": "2021", "last_revised_date": "2021", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "No durable Franklin city design-manual PDF found (CivicPlus IDs returned newsletters). Using Metro Nashville SWMM Vol 4 as Middle Tennessee urban MS4 BMP reference: 80% TSS reduction of average annual urban pollutant load; small frequent storms typically <1.1 inches drive selection/sizing.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Permanent / post-construction treatment practices", "Swales", "Sediment or detention ponds", "Pervious pavers / permeable concrete", "Infiltration BMPs", "Vegetated filters" ] }, "evidence": [ { "field": "design_criteria.water_quality_volume_method", "excerpt": "80% TSS reduction of an average annual urban pollutant load", "page_or_section": "Nashville SWMM Vol4" }, { "field": "practice_mentions.swale", "excerpt": "Permanent BMPs may include swales, sediment or detention ponds, and a variety of other features.", "page_or_section": "1.5 Temporary and Permanent BMPs, page 1-7" }, { "field": "practice_mentions.swale", "excerpt": "Significant offsite flows (especially concentrated flows) that drain onto disturbed areas or slopes should be controlled through use of continuous berms, earth dikes, drainage swales, and lined ditches", "page_or_section": "1.6.4.3 Site Perimeter, page 1-14" }, { "field": "practice_mentions.extended_detention", "excerpt": "Permanent BMPs may include swales, sediment or detention ponds, and a variety of other features.", "page_or_section": "1.5 Temporary and Permanent BMPs, page 1-7" }, { "field": "practice_mentions.extended_detention", "excerpt": "Metro's detention policies address this issue for new development.", "page_or_section": "1.3.1.2 Stream and Channel Erosion, page 1-3" }, { "field": "practice_mentions.wet_pond", "excerpt": "Excavate permanent stormwater detention ponds early in the project, use them as sedimentation ponds during construction", "page_or_section": "1.6.4.5 Internal Erosion, page 1-15" }, { "field": "enrich_notes", "excerpt": "Typically these events are less than 1.1-inches of rainfall and that fact was used in preparing the selection, sizing, approach, and maintenance criteria presented in the BMP fact sheets.", "page_or_section": "1.2 Stormwater Quality and Quantity Management, page 1-2" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder using Nashville Vol4 — replace when Franklin publishes a local stormwater design standards PDF. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.nashville.gov/sites/default/files/2021-08/SWMM-Vol4-01_SECTION_1_0_ALL.pdf", "landing_page_url": "https://www.franklintn.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "franklin-tn.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:21:57.954Z", "enrich_model": "composer-2.5:run-3f981524-fba3-493c-83f1-faa4173a47fc", "enrich_notes": "Provided excerpts cover Metro Nashville SWMM Vol. 4 Section 1 (introduction, stormwater quality context, EP&SC, temporary/permanent BMP overview) only; BMP fact sheets with facility-specific design dimensions are not in the corpus. Franklin placeholder uses Nashville Vol. 4 as regional reference. Small frequent storms described as typically less than 1.1 inches of rainfall for sizing context—not stated as a numeric WQv design depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "frisco-tx", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/frisco-tx/", "data_url": "https://stormwateratlas.com/data/manuals/frisco-tx.json", "document_metadata": { "jurisdiction_name": "City of Frisco", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Engineering Standards — Design Standards (Part A)", "version_or_edition": "October 2025", "adoption_or_effective_date": "2025-10-28", "last_revised_date": "2025-10-28", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 25, 100 ], "water_quality_volume_method": "Section 4 Drainage Design Requirements include stormwater quality treatment (4.18), detention/retention facility design (4.09), and sustainable development provisions. Street and enclosed-system conveyance sized with multi-frequency storms including 100-year street capacity / dry-lane criteria; references NCTCOG construction standards.", "peak_flow_calculation_method": [ "Rational Method / Q=CIA for enclosed systems and inlets", "Multi-frequency rainfall (2-, 5-, 25-, 100-year; Hydro-35 / TP-40 era tables referenced)", "Downstream assessment and detention sizing (4.03 / 4.09)", "100-year street capacity / dry-lane criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention / retention facilities", "Stormwater quality treatment BMPs", "Open channels / culverts / energy dissipators", "Erosion and sedimentation controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Frisco Engineering Standards", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Frisco", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Engineering Standards / Design Standards", "page_or_section": "Cover / TOC" }, { "field": "document_metadata.version_or_edition", "excerpt": "Table of Contents October 2025", "page_or_section": "TOC" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Standards Table of Contents October 2025 TC-1 Table of Contents Part A ñ Design Standards Page SECTION 1 GENERAL REQUIREMENTS 1-1 1.01 Short Title ..................................................................................................................1-2 1.0", "page_or_section": "p. 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "October 2025", "page_or_section": "Section headers" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Engineering Standards / NCTCOG", "page_or_section": "General" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year 5-year 25 year 100- year", "page_or_section": "Section 4.02" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "4.18 Stormwater Quality Treatment", "page_or_section": "Section 4 TOC" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "100-year runoff, Q=CIA (cfs)", "page_or_section": "Section 4 inlet design" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention/Retention Facility Design / Stormwater Quality Treatment", "page_or_section": "Section 4.09 / 4.18" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Stormwater quality volume is based on the first one-inch (1\") of rainfall.", "page_or_section": "Section 4.18.A.1 / Page 4-32" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The water quality volume is calculated by using the one-inch (1\") rainfall event", "page_or_section": "Section 4.18.B / Page 4-33" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Outfall shall include a pond drain with headwall and gate valve allowing for fully drained pond within a 24-hour period", "page_or_section": "Section 4.18.C.1.e / Page 4-34" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain time shall not exceed forty-eight (48) hours.", "page_or_section": "Section 4.18.C.2.e / Page 4-36" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The maximum ponding depth is twelve inches (12\") above finished grade and contained within the biofiltration system.", "page_or_section": "Section 4.18.C.2.d / Page 4-36" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "df = Filter bed depth (ft) 2.5 feet minimum", "page_or_section": "Section 4.18.C.2.j / Page 4-37" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "t = Drain time (seconds) Orifice sized for 24-48 hours of detention", "page_or_section": "Section 4.18.C.1.h / Page 4-35" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "tf = Design filter bed drain time (days) 2 days maximum", "page_or_section": "Section 4.18.C.2.j / Page 4-37" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Frisco 2025 Design Standards Part A; Section 4 drainage. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.friscotexas.gov/DocumentCenter/View/39413/2025-Design-Standards-ONLY", "landing_page_url": "https://www.friscotexas.gov/412/Engineering-Standards", "retrieved_at": "2026-08-10T08:45:22.876Z", "original_filename": "frisco-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "manufactured_treatment" ], "enriched_at": "2026-08-13T08:23:31.107Z", "enrich_model": "composer-2.5:run-5c1dabdb-d77c-4545-8c29-e9fe7508e612", "enrich_notes": "Frisco Engineering Standards Section 4.18 (Oct 2025): WQv from first 1 in rainfall (Rv=0.05+0.009I; WQV=1.0*Rv*A/12 acre-ft). Approved BMPs: extended detention (dry/wet pond per Section 4.09), biofiltration, mechanical separators; 80% TSS target. Extended detention: min 3 in WQ orifice; maintenance pond drain within 24 h; WQ orifice sized for 24–48 h detention. Wet pond: normal-pool WQ outfall, 5 ft littoral shelf 1 ft below normal pool. Biofiltration: max 5 ac per system; max 12 in ponding; drain ≤48 h; min 2.5 ft filter bed; 2-day max filter drain in sizing equation; underdrain and overflow (100-yr, opening ≥3 in above grade). Mechanical separators: iSWM WQ Manual §1.4 for peak WQ flow; 90% floatables; 250 µm sizing; RC manholes. No explicit SHWT separation, infiltration rate in/hr, permeable pavement, green roof, constructed wetland, or swale design dimensions in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "gainesville-fl", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/gainesville-fl/", "data_url": "https://stormwateratlas.com/data/manuals/gainesville-fl.json", "document_metadata": { "jurisdiction_name": "City of Gainesville (SRWMD criteria)", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II (Design Requirements for Stormwater Treatment and Management Systems)", "version_or_edition": "Effective July 2024", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 100 ], "water_quality_volume_method": "Minimum State water quality treatment requirements are those in statewide ERP Applicant's Handbook Volume I; Volume II requires all systems to recover treatment volumes within 72 hours (retention may use only percolation and evaporation; detention with filtration needs a safety factor of two). Quantity retention in closed basins is post- minus pre-development runoff for the 100-year critical event (max one-day duration). Flood storage recovery: one-half of total volume within seven days and total volume within 30 days after each design storm.", "peak_flow_calculation_method": [ "Pre- and post-development runoff hydrographs with detention/retention routing (stage-storage-discharge)", "Rational Method", "Natural Resources Conservation Service (NRCS) method", "USGS regression equations", "SCS Type II distribution on average antecedent moisture conditions", "Peak Rate Factor (K') method (conservative post-development K'=484)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention ponds", "Dry detention ponds", "Exfiltration trench systems", "Wet detention ponds", "Swale systems", "Vegetated natural buffers", "Borrow pits and ponds", "Dams and impoundments", "Sensitive karst area BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "FOR USE WITHIN THE GEOGRAPHIC LIMITS OF THE SUWANNEE RIVER WATER MANAGEMENT DISTRICT", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Such systems are regulated by the Suwannee River Water Management District (District) through the ERP program authorized under Section 373.4145, F.S.", "page_or_section": "Section 1.1.1 Introduction" }, { "field": "document_metadata.state_code", "excerpt": "Incorporated by Reference in Rules 62-330.010 and 40B-400.091, F.A.C.", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II (DESIGN REQUIREMENTS FOR STORMWATER TREATMENT AND MANAGEMENT SYSTEMS)", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Volume provides specific, detailed information to meet the water quality system and quantity design requirements of stormwater management systems. ... Both Applicant's Handbook Volumes I and II are adopted by reference in Chapter 62-330, F.A.C.", "page_or_section": "Section 1.1.1 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For projects which serve exclusively agricultural, forest, conservation, or recreational land uses, a design storm with a 10-year, 24-hour rainfall depth with SCS type II distribution ... shall be used. For projects which serve all other land uses, a design storm with 100-year critical duration rainfall depth with SCS type II distribution ... shall be used.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The applicant shall analyze the 100-year frequency (one percent annual chance) analysis of the 1-, 2-, 4-, 8-, and 24-hour durations for all stormwater systems.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For Alachua, Bradford, Dixie, Gilchrist, Lafayette, Levy, and Taylor counties: Frequency (years) ... 10 ... 25 ... 100", "page_or_section": "Appendix B – Design Storms" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All stormwater management systems must be designed to provide minimum State water quality treatment requirements as set forth in Applicant's Handbook Volume I.", "page_or_section": "Section 4.3 State Water Quality Standards" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All stormwater management systems shall be designed to recover treatment volumes within 72 hours. For retention systems, only percolation and evaporation may be used to reduce storage and treatment volumes in the system.", "page_or_section": "Section 4.4 Recovery" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required retention volume is the post-development runoff volume less the pre-development runoff volume for the 100-year critical event with a maximum duration of one day.", "page_or_section": "Section 3.3 Discharge Rates and Volumes (closed basin)" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "One-half of the total volume within seven days following the end of each design storm event, and 2. The total volume within 30 days following the end of each design storm event.", "page_or_section": "Section 3.4 Recovery" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "There are several equations available for calculating discharge including, but not limited to, the Rational Method, Natural Resources Conservation Service (NRCS) method, and USGS regression equations.", "page_or_section": "Section 3.3.1 Methodologies for Calculating Discharge" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "A peak discharge analysis typically consists of generating pre-development and post-development runoff hydrographs, routing the post-development hydrograph through a detention or retention basin, and sizing an overflow structure to control post-development discharges at or below pre-development discharge.", "page_or_section": "Section 3.3.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Peak Rate Factor reflects the effect of watershed storage on the hydrograph shape ... The most conservative approach is to use a K' = 484 for post-development.", "page_or_section": "Section 3.3.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "a design storm with a 10-year, 24-hour rainfall depth with SCS type II distribution falling on average antecedent moisture conditions shall be used.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The Best Management Practices (BMP)s below are the most frequently used BMPs in this District.", "page_or_section": "Part V – Best Management Practices" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5.1 Retention Pond ... 5.2 Dry Detention Pond ... 5.3 Exfiltration Trench Systems ... 5.4 Wet Detention Pond ... 5.5 Swale System ... 5.6 Vegetated Natural Buffers ... 5.7 Borrow Pits and Ponds ... 5.8 Dams and Impoundments ... 5.9 Sensitive Karst Area", "page_or_section": "Table of Contents / Part V" }, { "field": "practice_mentions.swale", "excerpt": "Swales shall be used for water quality treatment with a maximum slope of three-to-one (3:1) and erosion shall be controlled with grass or other equivalent method.", "page_or_section": "5.7.2 Criteria / page 11 (gainesville-fl-c0087)" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet detention systems are permanently wet ponds which are designed to slowly release collected stormwater runoff through an outlet structure.", "page_or_section": "5.4.1 Description / page 26 (gainesville-fl-c0101)" }, { "field": "practice_mentions.extended_detention", "excerpt": "5.2 Dry Detention Pond Design Criteria and Guidelines", "page_or_section": "PART V – BEST MANAGEMENT PRACTICES / page 3 TOC" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "5.3 Exfiltration Trench Systems Design Criteria and Guidelines", "page_or_section": "PART V – BEST MANAGEMENT PRACTICES / page 3 TOC" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The permanent pool shall be sized to provide at least a 14-day residence time based upon average wet season rainfall (rainfall occurring over the wetest four months of an average year). Additional permanent pool volume is required for wet detention systems which directly discharge to OFWs. The maximum depth of th", "page_or_section": "5.4.3 Permanent Pool / page 26 (truncated; no numeric depth in excerpt)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Municipal map coverage via SRWMD ERP AH Vol II. Canonical special_district record: fl-srwmd-erp-ah2. Previously mislabeled as county; reclassified to municipality proxy. Regional SRWMD ERP Applicant's Handbook Vol II (north-central Florida; Gainesville/Alachua is within district rainfall tables). Not a City of Gainesville municipal manual. Numeric first-flush inch depths live primarily in statewide AH Volume I; Vol II specifies recovery times, design storms (10-yr ag/recreation; 100-yr critical duration otherwise; Appendix B includes 10/25/100-yr depths), and BMP design. Jurisdiction coded as county per task guidance. Section 2.7 states no specified computer-model list.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "http://www.srwmd.state.fl.us/DocumentCenter/View/19233", "landing_page_url": "https://www.srwmd.state.fl.us/", "retrieved_at": "2026-08-08T11:46:29.939Z", "original_filename": "gainesville-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:25:52.831Z", "enrich_model": "composer-2.5:run-d6a75e8d-255e-4d86-ab04-6539d1f1bbef", "enrich_notes": "Provided corpus is mostly TOC repeats (page 3) plus partial BMP text. Wet detention §5.4.3 states permanent pool sizing by 14-day residence time (wet-season rainfall) but truncates before maximum depth. Sensitive karst §5.9.3 gives 3 ft soil over limestone and 10 ft max vertical staging—not mapped to SHWT separation or permanent pool depth fields. WQV inch depths and 72-hour treatment-volume recovery are referenced in atlas notes (Vol I / Vol II) but not stated numerically in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "garland-tx", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/garland-tx/", "data_url": "https://stormwateratlas.com/data/manuals/garland-tx.json", "document_metadata": { "jurisdiction_name": "City of Garland", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Technical Standards Manual", "version_or_edition": null, "adoption_or_effective_date": "2015-05-19", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "TSM Chapter 4 drainage includes detention/retention facility design (4.11) and stormwater management requirements (Section 6). Downstream assessment: no increases in water surface elevations for the 2-, 10-, and 100-year storm events.", "peak_flow_calculation_method": [ "Drainage plan and capacity analysis (TSM 4.04)", "Downstream assessment (TSM 4.02)", "Inlet location and capacity (4.09)", "Detention/retention facility design (4.11)", "2-/10-/100-year WSEL no-rise criterion" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Retention facilities", "Storm drain / curb inlets", "Construction stormwater quality BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Garland", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Garland", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Technical Standards Manual", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Garland Development Code (GDC) on Tuesday, May 19, 2015", "page_or_section": "TSM landing page / intro" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Technical Standards Manual", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "No increases in water surface elevations for the 2-, 10-, and 100-year storm events", "page_or_section": "Downstream assessment" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "4.11 Detention/Retention Facility Design", "page_or_section": "Chapter 4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Drainage Plan and Capacity Analysis (see TSM Section 4.04)", "page_or_section": "Submittals" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention/Retention Facility / Stormwater Quality BMPs", "page_or_section": "Chapter 4 / Section 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Verify design includes water quality features, detains first flush volume = (0.08 ft)(C)(A), or storm screening device used.", "page_or_section": "Detention Basins Checklist, page 354" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Define / verify maximum design WSEL for 2, 10 and 100-year and the first 1-inch of rainfall.", "page_or_section": "Detention Basins Checklist, page 354" }, { "field": "practice_mentions.extended_detention", "excerpt": "Extended Detention", "page_or_section": "TSM Section 4.20 Sustainable Development, page 120" }, { "field": "practice_mentions.bioretention", "excerpt": "Bio Retention", "page_or_section": "TSM Section 4.20 Sustainable Development, page 120" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roofs", "page_or_section": "TSM Section 4.20 Sustainable Development, page 120" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Modular Porous Paver Systems · Porous Concrete", "page_or_section": "TSM Section 4.20 Sustainable Development, page 120" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales", "page_or_section": "TSM Section 6 – Stormwater Management Requirements, page 150" }, { "field": "practice_mentions.wet_pond", "excerpt": "Detention ponds · Retention ponds", "page_or_section": "TSM Section 6, page 150; Facilities with permanent pools shall address dewatering procedures, Section 4.11, page 105" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "When storm water screening device used, provide plan and details.", "page_or_section": "Detention Basins Checklist, page 354" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Large TSM; drainage Chapter 4 confirmed. Numeric detention volume formulas may need deeper pull. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.garlandtx.gov/DocumentCenter/View/459", "landing_page_url": "https://www.garlandtx.gov/272/Technical-Standards-Manual", "retrieved_at": "2026-08-10T08:30:22.061Z", "original_filename": "garland-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 0.96, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:26:31.540Z", "enrich_model": "composer-2.5:run-3b3fea09-b3bd-49bf-bca7-485e45589fce", "enrich_notes": "Garland TSM references NCTCOG/iSWM and EPA LID resources for sustainable BMP sizing; local checklist defines first-flush detention as (0.08 ft)(C)(A) or storm screening/perforated riser per NCTCOG. Detention design uses 2-, 10-, and 100-year WSEL with first 1-inch rainfall; 1 ft freeboard above 100-year WSEL to emergency spillway crest. Low-flow dewatering device minimum 4-inch diameter; pond access 10 ft minimum unobstructed, max 10% traverse slope (Section 4.11) or 20% on checklist variants.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "gastonia-nc", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/gastonia-nc/", "data_url": "https://stormwateratlas.com/data/manuals/gastonia-nc.json", "document_metadata": { "jurisdiction_name": "City of Gastonia", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (city MS4 / MDC)", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Combined SCM design volume handles the required storm depth for the applicable NCDEQ program (e.g., 1\" under 15A NCAC 02H .1021(6) for non-coastal HQW/ORW).", "peak_flow_calculation_method": [ "NCDEQ MDC outlet erosion protection for 10-year peak" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "SCM devices per 15A NCAC 02H .1051–.1062" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NCDEQ Design Manual.", "fields_not_found": [] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.cityofgastonia.com/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "gastonia-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:26:54.195Z", "enrich_model": "composer-2.5:run-d35d0d63-b4b0-4a48-85f8-11905cf6cbbb", "enrich_notes": "Corpus is NCDEQ C-0 general MDC only (pages 2–7); device-specific MDC under Rules .1051–.1062 and Part C are not included. Required storm depth cited as one inch for non-coastal HQW/ORW under 15A NCAC 02H .1021(6); combined SCM design volume must handle applicable program storm depth. Dewatering required qualitatively without max drawdown hours. Side slopes vegetated cover max 3:1 H:V; maintenance access min 10 ft width (25 ft recommended for wet ponds).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "grand-prairie-tx", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/grand-prairie-tx/", "data_url": "https://stormwateratlas.com/data/manuals/grand-prairie-tx.json", "document_metadata": { "jurisdiction_name": "City of Grand Prairie", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "iSWM Criteria Manual for Site Development and Construction", "version_or_edition": "Revised January 2015", "adoption_or_effective_date": "2015-01", "last_revised_date": "2015-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 25, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQv) based on 1.5 inches of rainfall (85th percentile storm). Streambank Protection: control 1-year, 24-hour storm; Conveyance: 25-year; Flood Mitigation: 100-year.", "peak_flow_calculation_method": [ "Rational Method", "SCS Unit Hydrograph Method", "Streambank Protection Volume (SPV)", "25-year conveyance / 100-year flood mitigation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Enhanced swales", "Detention", "Sand filters / filter boxes", "Infiltration wells and trenches" ] }, "evidence": [ { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "Section 3.2.3 Option 2, page 29" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treat the Water Quality Protection Volume ... for runoff resulting from rainfall of 1.5 inches (85th percentile storm).", "page_or_section": "Section 3.2.3 Option 2, page 28" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Modular Porous Paver Systems Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet Pond Limit maximum normal pool depth to about 4 ft (dugout)", "page_or_section": "Table 3.19 Physiographic Factors, page 61" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Third-party sources could include Technology Acceptance Reciprocity Partnership, Technology Assessment Protocol – Ecology, or others.", "page_or_section": "Table 3.2 footnote, TriSWM Appendix page 112" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "NCTCOG iSWM regional criteria — confirm city adoption / local amendments. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://iswm.nctcog.org/Documents/iSWM_Criteria_Manual_01142015.pdf", "landing_page_url": "https://iswm.nctcog.org/criteria-manual.html", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "grand-prairie-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "Technology Acceptance Reciprocity Partnership, Technology Assessment Protocol – Ecology", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:27:29.897Z", "enrich_model": "composer-2.5:run-652503d5-5e33-4e50-84ae-ca83465d673d", "enrich_notes": "Criteria Manual defers detailed BMP sizing to the Site Development Controls Technical Manual. Table 3.17/3.4 list practice-specific depth-to-water-table values (e.g., 2 ft bioretention/detention, 4 ft infiltration trenches) rather than one site-wide SHWT separation. Wet pond normal pool depth is stated as a maximum (~4 ft dugout), not a required minimum permanent pool depth.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "grand-rapids-mi", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/grand-rapids-mi/", "data_url": "https://stormwateratlas.com/data/manuals/grand-rapids-mi.json", "document_metadata": { "jurisdiction_name": "City of Grand Rapids", "jurisdiction_level": "municipality", "state_code": "MI", "document_title": "Stormwater Standards Manual", "version_or_edition": "Rev. 04.29.2021", "adoption_or_effective_date": null, "last_revised_date": "2021-04-29", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 100 ], "water_quality_volume_method": "Water quality “first flush”: treat runoff from 1 inch of rain over the project site (≈90th percentile / first flush), achieving ≥80% TSS reduction or equivalent discharge concentration. Channel protection: match pre-development runoff volume and rate for storms up to the 2-year, 24-hour event (or detain 2-year, 24-hour for 24 hours). Flood control for 100-year as applicable by sewershed.", "peak_flow_calculation_method": [ "Water quality volume / first flush treatment", "Channel protection volume retention or extended detention", "Flood control / 100-year peak criteria by sewershed", "Infiltration BMP evaluation for WQ and channel protection" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration BMPs", "Detention / retention for channel protection", "Structural BMPs (Green Book / Red Book specs)", "Water quality treatment BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Grand Rapids Kent County, Michigan", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Grand Rapids", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Rev. 04.29.2021", "page_or_section": "Header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Stormwater Ordinance Chapter 32 / Chapter 67", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year, 24-hour / 100-year storm", "page_or_section": "Channel Protection / Flood Control" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat the runoff generated from 1 inch of rain / \"first flush\"", "page_or_section": "Water Quality" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Channel Protection / Flood Control performance standards", "page_or_section": "Part IV / Table 1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "infiltration BMPs / Structural Best Management Practices", "page_or_section": "Design Process / Green Book" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "This storm is approximately equivalent to 1 inch of rain (1.00 inch for Michigan Climatic Zone 8 per DEQ memo", "page_or_section": "Part 3, II. STANDARDS A. Water Quality, page 21" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treat the runoff generated from 1 inch of rain over the project site (i.e. the 90% annual non-exceedance storm)", "page_or_section": "Table 1 – Minimum Required Stormwater Standards, page 20" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Extended detention is defined as holding the stormwater runoff volume and releasing it gradually over a period of 24 hours with a drawdown time no greater than 72 hours.", "page_or_section": "Part 3, II. STANDARDS A. Water Quality, page 21" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention of the 2-year, 24-hour storm for a period of 24 hours resulting in a drawdown time no greater than 72 hours.", "page_or_section": "Table 1 / Part 3 Channel Protection, page 20" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Simply using a lower extended detention release rate will violate the 72 hour drawdown time requirement.", "page_or_section": "Part 4, Extended Detention, page 47" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Vegetated Swale Provide a 20-foot minimum length at a maximum slope of 2% with a 1-foot high check dam", "page_or_section": "Part 3, II. STANDARDS D. Pretreatment, page 24" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Grand Rapids Stormwater Standards Manual Apr 2021. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.grandrapidsmi.gov/media/4vfaiq3n/gr-stormwater-standard-manual-04292021.pdf", "landing_page_url": "https://www.grandrapidsmi.gov/", "retrieved_at": "2026-08-10T08:56:34.266Z", "original_filename": "grand-rapids-mi.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:27:46.890Z", "enrich_model": "composer-2.5:run-f1429bc4-d3d8-45fb-906b-24bb1572f205", "enrich_notes": "Water quality treated as 1 inch (90% annual non-exceedance; 1.00 in Zone 8). Channel protection alternative: extended detention with 24-hour detention period and drawdown not greater than 72 hours. Design infiltration is field rate divided by 2, capped by Table 5 texture classes; soils below 0.24 in/hr design rate unsuitable for infiltration BMPs. Detailed BMP dimensions refer to City Green Infrastructure Standards (Green Book), not in this corpus. Coldwater stream policy: detention times max 12 hours for detention ponds.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "greensboro-nc", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/greensboro-nc/", "data_url": "https://stormwateratlas.com/data/manuals/greensboro-nc.json", "document_metadata": { "jurisdiction_name": "City of Greensboro", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (city MS4 / MDC)", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Combined SCM design volume handles the required storm depth for the applicable NCDEQ stormwater program (e.g., 1\" under 15A NCAC 02H .1021(6) for non-coastal HQW/ORW runoff treatment).", "peak_flow_calculation_method": [ "NCDEQ MDC outlet erosion protection for 10-year peak" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "SCM devices per 15A NCAC 02H .1051–.1062" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" }, { "field": "practice_mentions.bioretention", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.swale", "excerpt": "vegetated swales, level spreader-filter strips, and berms", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.wet_pond", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice at the invert", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NCDEQ Design Manual (Cary/Wilmington pattern). City portal PDF may be 403-blocked.", "fields_not_found": [] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.deq.nc.gov/about/divisions/energy-mineral-and-land-resources/stormwater/stormwater-program/stormwater-design-manual", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "greensboro-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:28:06.373Z", "enrich_model": "composer-2.5:run-a03eeaab-3861-4fee-86e5-d865d1ef263b", "enrich_notes": "Corpus is NCDEQ C-0 General MDC only (pages 2–7); device-specific MDC in Part C / Rules .1051–.1062 not included. Required storm depth cited via 15A NCAC 02H .1021(6) example (1 inch non-coastal HQW/ORW). Dewatering required but no max drawdown hours stated.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "greenville-sc", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/greenville-sc/", "data_url": "https://stormwateratlas.com/data/manuals/greenville-sc.json", "document_metadata": { "jurisdiction_name": "City of Greenville", "jurisdiction_level": "municipality", "state_code": "SC", "document_title": "Best Management Practice (BMP) Design Manual / GSMM Unified Stormwater Sizing Criteria (SC MS4 pattern)", "version_or_edition": "January 10, 2014 (Columbia manual used as SC municipal BMP pattern)", "adoption_or_effective_date": "2014-01-10", "last_revised_date": "2014-01-10", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 25, 100 ], "water_quality_volume_method": "South Carolina MS4s commonly apply Unified Stormwater Sizing Criteria / GSMM methods: treat runoff from a ~1.2-inch rainfall event (WQv), Channel Protection Volume for the 1-year storm, and overbank flood protection (e.g., Q25). Greenville-specific design manual PDF not located; Columbia BMP Design Manual used as in-state municipal pattern.", "peak_flow_calculation_method": [ "Unified Stormwater Sizing Criteria (WQv / CPv)", "GSMM structural BMP methods", "Overbank Flood Protection (Q25)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water quality BMPs (GSMM structural controls)", "Detention ponds", "Pretreatment practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Greenville SC — coverage via Columbia BMP Design Manual / GSMM sizing pattern (needs local confirmation)", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = (1.2)(Rv)(A)/12 where: WQv = water quality volume 1.2-inch rainfall (in acre-feet)", "page_or_section": "2.1 Water Quality (WQv), page 23" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "designed to store the runoff from the contributing area of the site from a 1.2-inch rainfall event", "page_or_section": "1.4.1 Design Requirements, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "release the accumulated water quality volume (WQv) over a minimum period of 24-hours", "page_or_section": "1.4.1 Design Requirements, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "This volume shall be released for a minimum period of 24-hours when a detention pond is used", "page_or_section": "1.2.3 Critical Water Bodies, page 9" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool depths must be ≥ 4 feet to reduce mosquito breeding", "page_or_section": "3.1.2 Accepted Quantity Controls / Table 3.2, pages 35, 39" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "designed to completely drain to a dry condition within 72 hours", "page_or_section": "3.1.2 Accepted Quantity Controls, page 35" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "channel protection criteria specifies that 24 hours of extended detention be provided for runoff generated by the 1-year, 24-hour rainfall event", "page_or_section": "2.2 Channel Protection (CPv), page 24" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder using Columbia SC BMP manual as SC municipal GSMM pattern — replace with Greenville city manual when found.", "fields_not_found": [] }, "source": { "document_url": "https://columbiascwater.net/wp-content/uploads/2018/08/bmpmanual.pdf", "landing_page_url": "https://www.greenvillesc.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "greenville-sc.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:28:37.924Z", "enrich_model": "composer-2.5:run-ab2c7c3e-d449-4e51-bfed-c386d295bf7e", "enrich_notes": "Corpus is City of Columbia BMP manual used as Greenville SC placeholder; GSMM Sections 3.2–3.4 cited for detailed BMP sizing. WQv uses 1.2-inch rainfall in USC formula; permanent-pool WQ structures use 0.6-inch event storage (1.4.1). CPv 1-year rainfall depth 3.1 inches. Stormwater wetlands listed as not recommended in Columbia manual.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "gulfport-ms", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/gulfport-ms/", "data_url": "https://stormwateratlas.com/data/manuals/gulfport-ms.json", "document_metadata": { "jurisdiction_name": "City of Gulfport", "jurisdiction_level": "municipality", "state_code": "MS", "document_title": "MDEQ Volume 2 Stormwater Runoff Management Manual", "version_or_edition": "Published 2011", "adoption_or_effective_date": "2011", "last_revised_date": "2011", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50 ], "water_quality_volume_method": "Capture and treat a water quality volume typically equal to the first 1 inch or first 1.5 inches of rainfall (Schueler's Simple Method). Wet detention — first 0.5 inch of runoff or 1.5 inches from impervious; dry retention / wetlands — first 1.0 inch of runoff or 2.5 inches from impervious.", "peak_flow_calculation_method": [ "SCS Runoff Curve Number Method", "Short Cut Floodrouting Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration / Filtration / Retention-Detention BMPs", "Manufactured stormwater treatment systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Gulfport MS4 follows MDEQ Volume 2", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Required volume: first 1.0 inch of runoff or 2.5 inches from impervious areas, whichever is greater.", "page_or_section": "Retention/Detention, Dry Retention Systems, page 196 (4-165)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration devices must be able to completely dewater within 5 days.", "page_or_section": "Infiltration, Length Width Depth and Geometry, page 106 (4-75)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Water must then drain to a level 24 inches below the surface of the cell within 48 hours (maximum)", "page_or_section": "Filtration, Bioretention Drainage Considerations, page 138 (4-107)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "bioretention areas require a minimum depth to groundwater of 2 feet", "page_or_section": "Introduction, page 13 (1-8)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "provide significant separation distance (2 to 5 feet) from the bottom of the infiltration basin and the seasonally high groundwater table", "page_or_section": "Infiltration Basin Groundwater, page 106 (4-75)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high water table must be at least 2 ft below the base of the permeable pavement or gravel storage layer", "page_or_section": "PICP Design Criteria, page 115 (4-84)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Basin floor should be at least three feet above the seasonal high groundwater table elevation", "page_or_section": "Dry Retention Systems, page 196 (4-165)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "underlying soils must have an infiltration rate of 0.52 inch per hour or greater", "page_or_section": "Infiltration Trench Soils/Topography, page 110 (4-79)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If in situ soil permeability is less than 2 inches/hour, the bioretention facility will likely have an underdrain system", "page_or_section": "Filtration, Bioretention Step 6, page 138 (4-107)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Discharge one-half the appropriate treatment volume of stormwater specified above between 24-30 hours following a storm event", "page_or_section": "Dry Retention Systems, page 196 (4-165)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Contain areas of standing water for no more than 3 days following a storm event", "page_or_section": "Dry Retention Systems, page 196 (4-165)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Average flow path through the basin should have a length-to-width ratio of at least 3:1", "page_or_section": "Dry Retention Systems, page 196 (4-165)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Grassed swales should be used on sites with relatively flat slopes of less than 4 percent slope; 1 to 2 percent slope is recommended", "page_or_section": "Infiltration, Grassed Swale Slope, page 96 (4-65)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via MDEQ Vol 2 (Jackson pattern).", "fields_not_found": [] }, "source": { "document_url": "https://www.mdeq.ms.gov/wp-content/uploads/2017/05/Volume_2.pdf", "landing_page_url": "https://www.mdeq.ms.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "gulfport-ms.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 120, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.52, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:29:24.429Z", "enrich_model": "composer-2.5:run-30cbd341-52a3-444a-8308-96e8ceeaf115", "enrich_notes": "MDEQ Vol. 2 (Gulfport/Jackson pattern). Dry retention WQV: first 1.0 in runoff or 2.5 in from impervious. SHWT separation commonly 2 ft (24 in); dry retention basin floor ≥3 ft (36 in) above SHWT. Bioretention: max 12 h surface ponding, drain ponded volume within 48 h; underdrain if native soil <2 in/hr. Infiltration devices: dewater within 5 days; soils ≥0.52 in/hr for trenches. ED dry retention: discharge half treatment volume in 24–30 h; standing water ≤3 days; L:W ≥3:1. Grassed swales: 1–2% longitudinal slope recommended, <4% max. Green roofs: slopes >20° need retention systems (degrees only in text). PICP/permeable: SHWT ≥2 ft below storage base; slopes >2% need extra design.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "harrisburg-pa", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/harrisburg-pa/", "data_url": "https://stormwateratlas.com/data/manuals/harrisburg-pa.json", "document_metadata": { "jurisdiction_name": "City of Harrisburg", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual (capital / Act 167)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "PA PCSM Manual pollutant-load approach coupling volume and water quality management: land-cover pollutant concentrations applied to runoff, volume reductions through SCMs credited, and post-construction loads compared to pre-construction. Capital-city Act 167 / MS4 programs require BMPs consistent with the Pennsylvania Stormwater BMP / PCSM Manual.", "peak_flow_calculation_method": [ "PA PCSM / Stormwater BMP Manual methods", "Act 167 stormwater management ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Volume-reducing SCMs", "Water quality SCMs", "Post-construction BMPs per PA Manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "inches in Pittsburgh, 40.9 inches in Harrisburg, and 41.5 inches in Philadelphia (Arguez et al. 2012). Pennsylvania typically experiences the highest rainfall depths in the summer months with the lowest precipitation amount experienced in January and February. It is important", "page_or_section": "pp. 393–394" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DRAFT / Page 1-3 1.1 OVERVIEW OF PCSM MANUAL This PCSM Manual establishes DEP-approved procedures for conducting PCSM stormwater analyses and provides SCM standards that can be used for regulatory compliance under Chapter 102. These procedures and standards may be applied to he", "page_or_section": "p. 12" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Permanent pool volume should hold the runoff generated by 1.2-inch/2-hour rainfall over the contributing drainage area.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Page 3-135 / Section 3.5.4 Infiltration Trench" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / Page B-31" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil Media Depth Min. ... Min. 18 in [Bioretention column, Table 3-90]", "page_or_section": "Table 3-90 / Page 3-310" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum Ponding/Storage Depth ... 2 ft [3.6.1 Bioretention, Table 3-90]", "page_or_section": "Table 3-90 / Page 3-310" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Permeable pavement materials with greater than or equal to one foot of storage underneath are considered permeable pavement systems with underground storage", "page_or_section": "Page 3-126 / Section 3.5.3 Permeable Pavement" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Temporary pool should draw down to the permanent pool elevation within three days.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio should be at least two to one.", "page_or_section": "Page 3-205 / Section 3.6.6 Engineered Stormwater Treatment Wetland" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom widths range from two feet to eight feet.", "page_or_section": "Page 3-96 / Vegetated Conveyance SCM" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Soil Media Depth Min. ... Min. 3 in [Green Roof column, Table 3-90]", "page_or_section": "Table 3-90 / Page 3-310" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via PA PCSM Manual (Allentown pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_parameters.shwt_separation_inches" ] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "harrisburg-pa.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:31:35.967Z", "enrich_model": "composer-2.5:run-aa95948f-6b9f-4503-8bfd-e21288d2c7bf", "enrich_notes": "PA PCSM Manual (Harrisburg/Act 167): WQ/MRC routing uses 1.2 in/2-hr storm; infiltration SCMs generally require 24 in (2 ft) separation to SHWT/limiting zone; drawdown/ponding limits are SCM-specific (48–96 hr ponding in Table 3-90; 72 hr drawdown to native soil common for trenches and permeable systems). Bioinfiltration vs bioretention vs MRC bioretention differ by infiltration thresholds (0.25 and 0.4 in/hr), not a single design infiltration rate.", "enrich_schema_version": 2, "fields_not_found": [ "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "hartford-ct", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/hartford-ct/", "data_url": "https://stormwateratlas.com/data/manuals/hartford-ct.json", "document_metadata": { "jurisdiction_name": "City of Hartford", "jurisdiction_level": "municipality", "state_code": "CT", "document_title": "Connecticut Stormwater Quality Manual (city follows CT DEEP 2024 Manual)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-03-30", "last_revised_date": "2024-03-26", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV = (P)(R)(A)/12 where P = 1.3 inches (90th percentile rainfall event), R = 0.05 + 0.009(I).", "peak_flow_calculation_method": [ "NRCS Curve Number method", "TR-20", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "WinTR-55", "HydroCAD", "TR-20" ], "approved_bmp_categories": [ "Pretreatment BMPs", "Infiltration BMPs", "Filtering BMPs", "Stormwater Pond BMPs", "Stormwater Wetland BMPs", "Water Quality Conveyance BMPs", "Stormwater Reuse BMPs", "Proprietary BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Hartford follows CT Stormwater Quality Manual 2024", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "𝑊𝑊𝑊𝑊𝑊𝑊 = (𝑃𝑃)(𝑅𝑅)(𝐴𝐴) 12 where: WQV = water quality volume (cubic feet) P = 1.3 inches (90th percentile rainfall event) R = volumetric runoff coefficient = 0.05+0.009( I) I = post- development impervious area (percent) after application of non-structural LID site p", "page_or_section": "p. 53" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.3 inches (90th percentile rainfall event)", "page_or_section": "Chapter 4, page 53" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention system should completely drain in 48 hours or less after the end of the design storm", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "For infiltration systems, at least 3 feet of separation is recommended", "page_or_section": "Chapter 10, page 194" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered bioretention soil media should have a depth of 24 to 48 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for water quality storm: 12 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "design infiltration rate used for system sizing and drain time analysis should be equal to 50% of the slowest observed field infiltration rate of the underlying soils or 0.5 inches per hour", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention basin should completely drain within 48 hours after the end of a storm", "page_or_section": "Chapter 13 – Dry Extended Detention Basin, page 467" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width Minimum: 2 feet", "page_or_section": "Chapter 13 – Wet Water Quality Swale, page 421" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green Roof Ground Slope Not Applicable (max 20% roof slope)", "page_or_section": "Chapter 8, Table 8-3, page 140" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Capital / municipal coverage via CT Stormwater Quality Manual 2024. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://portal.ct.gov/-/media/deep/water/water_quality_management/guidance/swm_mar_2024.pdf", "landing_page_url": "https://portal.ct.gov/DEEP/Water-Regulating-and-Discharges/Stormwater/Stormwater-Manual", "retrieved_at": "2026-08-10T09:54:53.524Z", "original_filename": "hartford-ct.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 20, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:32:24.185Z", "enrich_model": "composer-2.5:run-edd0cd95-59e4-41f0-9660-3fe2523a7059", "enrich_notes": "Connecticut Stormwater Quality Manual (2024); Hartford follows CT DEEP. WQV uses P=1.3 in (90th percentile), R=0.05+0.009(I). Infiltration suitability threshold 0.3 in/hr; bioretention sizing uses 0.5 in/hr media design rate or 50% field rate. SHGT separation: 3 ft (36 in) recommended for infiltration BMP bottoms; 1 ft above SHGT for unlined filtering systems; 2 ft reduction allowed in limited cases.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "helena-mt", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/helena-mt/", "data_url": "https://stormwateratlas.com/data/manuals/helena-mt.json", "document_metadata": { "jurisdiction_name": "City of Helena", "jurisdiction_level": "municipality", "state_code": "MT", "document_title": "Montana Circular DEQ-8 — Subdivision Storm Water Drainage Standards (capital)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024", "last_revised_date": "2024", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Initial Storm Water Facility must infiltrate, evapotranspire, and/or capture for reuse post-development runoff from the first 0.5 inches of rainfall on impervious areas (V = 0.5 × Aimp / 12). BMPs per Montana Post-Construction Storm Water BMP Design Manual may satisfy if they treat/remove 80% TSS.", "peak_flow_calculation_method": [ "Rational Method", "Modified Rational Method", "TR-55 / SCS Curve Number Method", "Storage-Indication Routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Initial Storm Water Facility", "Retention / Detention / Infiltration Facilities", "Bioretention", "Pre-treatment Facilities", "Conveyance Structures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Helena capital MS4 follows Montana DEQ-8 stormwater standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "first 0.5 inches of rainfall on impervious areas", "page_or_section": "DEQ-8" }, { "field": "max_drawdown_hours", "excerpt": "Retention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "5.1 GENERAL, page 29" }, { "field": "max_drawdown_hours", "excerpt": "Detention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "6.1 GENERAL, page 31" }, { "field": "shwt_separation_inches", "excerpt": "For detention facilities that have a minimum one-foot separation from the bottom of the facility to the seasonally high groundwater or bedrock layer", "page_or_section": "6.2 DESIGN, page 31" }, { "field": "shwt_separation_inches", "excerpt": "Be constructed such that the bottom of the facility is one foot above any limiting layer.", "page_or_section": "5.2 DESIGNS, page 29" }, { "field": "practice_mentions", "excerpt": "The BMPs may include infiltration basins, bioretention, biofiltration swales, extended detention basins, wet detention basins, and proprietary treatment devices. Permeable pavement systems and dispersion BMPs are not allowed as the initial storm water facility.", "page_or_section": "3.5 / standard plans BMP allowance, page 16" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "DEQ-8 is subdivision stormwater drainage standards — partial design coverage for capital MS4.", "fields_not_found": [] }, "source": { "document_url": "https://deq.mt.gov/files/Water/Forms/DEQ_8_2024_FINAL_2024_09_20.pdf", "landing_page_url": "https://deq.mt.gov/water", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "helena-mt.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:33:50.516Z", "enrich_model": "composer-2.5:run-029a41c5-0792-4338-9b0b-7bb52f5dc9de", "enrich_notes": "DEQ-8 defers detailed BMP sizing to Montana Post-Construction Storm Water BMP Design Manual (2017). Initial-storm volume (0.5 in on impervious) appears in atlas metadata but not in supplied corpus chunks. Infiltration facilities require 24 in (2 ft) above a limiting layer (7.2.A), stricter than detention/retention 12 in (1 ft) to seasonally high groundwater or limiting layer (5.2.B, 6.2). Infiltration must drain within 48 h (7.2.D). Design infiltration rate uses measured rate ÷ 2.0 safety factor (Appendix A); Table 3 rates not included in excerpts. Permeable pavement and dispersion BMPs are prohibited as the initial storm water facility (3.5).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "hialeah-fl", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/hialeah-fl/", "data_url": "https://stormwateratlas.com/data/manuals/hialeah-fl.json", "document_metadata": { "jurisdiction_name": "City of Hialeah", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "SFWMD Environmental Resource Permit Applicant's Handbook Volume II (Basis of Review)", "version_or_edition": "Effective July 4, 2010 (draft ERP Vol II mirror)", "adoption_or_effective_date": "2010-07-04", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "SFWMD ERP AH Vol II: wet detention volume for the first inch of runoff from the developed project (or 2.5 in over the basin for projects with ≥50% impervious / special cases per rule); dry detention = 75% of wet; retention = 50% of wet. Quantity: off-site discharge typically based on 3-day / 25-year storm unless local criteria are more stringent; 100-year / 3-day considered for flood protection / finished floors.", "peak_flow_calculation_method": [ "3-day / 25-year off-site discharge (default)", "100-year / 3-day flood considerations", "Retention / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Dry retention / detention", "Exfiltration trenches", "Swales / pretreatment", "Other SFWMD-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Hialeah is within SFWMD and follows ERP Applicant's Handbook Vol II", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet detention volume shall be provided for the first inch of runoff", "page_or_section": "SFWMD Vol II water quality criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project, or the total runoff of 2.5 inches times the percentage of imperviousness, whichever is greater.", "page_or_section": "4.2.1 Volumetric Requirements (a)(1), page 17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The required water quality system for one inch of runoff detention or one half inch of runoff retention in the master system for the total developed site.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.3.1 Description, page 26" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The individual sites must provide the remainder (2.5\" x % impervious - one inch) which may be in exfiltration trench.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry retention/detention areas shall have mechanisms for returning the groundwater level in the area to the control elevation.", "page_or_section": "5.3.3 Dry Retention/Detention Areas (a), page 26" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SFWMD ERP AH Vol II. Prefer city-specific drainage criteria if a durable public PDF appears.", "fields_not_found": [] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/draft_erp%20vol%20ii%20swerp%20ii_2104_10.pdf", "landing_page_url": "https://www.hialeahfl.gov/258/Engineering", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "hialeah-fl.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:34:26.111Z", "enrich_model": "composer-2.5:run-0cfc49fd-9d67-4cbe-b786-ae747765ff83", "enrich_notes": "Source is SFWMD ERP Applicant's Handbook Vol. II (Aug 2014), applied via Hialeah/SFWMD ERP. Wet-detention WQ volume basis explicitly uses the first 1 inch of runoff from the developed project, or 2.5 inches times percent impervious (whichever is greater). Subdivided commercial master systems may require 1 inch detention or 0.5 inch retention in the master system, with remainder (2.5 in × % impervious − 1 in) on individual sites (exfiltration trench allowed on lots, not in master). Residential minimum drainage cites 3/8 inch per day bleed capability with water-surface lowering in 12 days or less (not stated in hours). Detention/control excavations limited to max 6 ft below natural ground. Subsurface exfiltration requires site test data; no handbook design infiltration rate in in/hr in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "high-point-nc", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/high-point-nc/", "data_url": "https://stormwateratlas.com/data/manuals/high-point-nc.json", "document_metadata": { "jurisdiction_name": "City of High Point", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "Stormwater Best Management Practices Design Manual", "version_or_edition": "Effective January 1, 2009", "adoption_or_effective_date": "2009-01-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Adopts NC DWQ/DEQ Stormwater BMP Manual jurisdiction-wide (Phase II). WS-IV high-density: control first 1\" of rainfall (and 85% TSS) where BUA >24% (or >12% in lower Randleman). City-extra: developments with BUA between 6% and those thresholds require additional BMPs controlling the first ½\" (natural infiltration, dry detention, infiltration trenches). Wet detention principal spillway = 10-year pre-development; emergency spillway = 100-year; ≥1 ft freeboard to dam crest.", "peak_flow_calculation_method": [ "NCDEQ / DWQ BMP Manual methods", "Wet detention: post ≤ pre 10-year principal spillway", "Emergency spillway sized for 100-year" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "NCDEQ / DWQ BMP Manual practices", "Wet detention basins (city extras)", "Natural infiltration areas", "Dry detention ponds", "Infiltration trenches", "Other BMPs controlling first 0.5\" rainfall" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Stormwater Best Management Practices Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "the City of High Point has adopted the Division of Water Quality’s Stormwater Best Management Practices Manual", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "must control the first 1” of rainfall ... Additional BMPs ... control the first ½” of rainfall", "page_or_section": "Introduction" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "All WS-IV water supply watersheds using the high-density option must control the first 1\" of rainfall on any site that exceeds 24% built-upon area.", "page_or_section": "INTRODUCTION, page 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In the lower Randleman watershed, any site that exceeds 12% built-upon area must control the first 1\" of rainfall.", "page_or_section": "INTRODUCTION, page 2" }, { "field": "practice_mentions.wet_pond", "excerpt": "In addition to North Carolina Division of Water Quality BMP Manual, Chapter 10, Wet Detention Basin, the City of High Point requires the following additional wet detention basin design elements:", "page_or_section": "INTRODUCTION, page 2" }, { "field": "practice_mentions.extended_detention", "excerpt": "Additional BMPs include natural infiltration areas, dry detention ponds, and infiltration trenches.", "page_or_section": "INTRODUCTION, page 2" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Additional BMPs include natural infiltration areas, dry detention ponds, and infiltration trenches.", "page_or_section": "INTRODUCTION, page 2" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Additional BMPs include natural infiltration areas, dry detention ponds, and infiltration trenches.", "page_or_section": "INTRODUCTION, page 2" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://www.highpointnc.gov/DocumentCenter/View/1533", "landing_page_url": "https://www.highpointnc.gov/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "high-point-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "wet_pond" ], "enriched_at": "2026-08-13T08:34:46.687Z", "enrich_model": "composer-2.5:run-0c96bfe6-64a2-4ce0-a4e0-81a3e01911bb", "enrich_notes": "Adopts NC DWQ Stormwater BMP Manual jurisdiction-wide. WS-IV high-density: first 1 inch rainfall and 85% TSS where BUA exceeds 24% (12% in lower Randleman). City additional BMPs for BUA between 6% and those thresholds require control of first 0.5 inch via natural infiltration areas, dry detention ponds, infiltration trenches, or other BMPs controlling first 0.5 inch. Wet detention per NC DWQ Ch. 10 plus city extras: principal spillway 10-year pre-development (post ≤ pre for 10-year); emergency spillway 100-year; minimum 1 ft between principal and emergency spillway elevations; minimum 1 ft freeboard from 100-year pool to dam crest; minimum 2 ft between emergency spillway and dam top. Principal spillway barrel minimum 15 inches diameter. Not a standalone numeric design chapter—detailed SCM parameters deferred to NC DWQ manual except wet detention spillway/freeboard items above.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "houston-tx", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/houston-tx/", "data_url": "https://stormwateratlas.com/data/manuals/houston-tx.json", "document_metadata": { "jurisdiction_name": "City of Houston", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Infrastructure Design Manual Chapter 9 Stormwater Design and Water Quality Requirements", "version_or_edition": "07-01-2022", "adoption_or_effective_date": "2022-07-01", "last_revised_date": "2022-07-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": "At a minimum, permanent stormwater quality BMPs for new development and significant redevelopment must treat the first 1/2 inch of runoff (except as noted in the Stormwater Quality Guidance Manual or Minimum Design Criteria); LID features may also store/treat a water quality volume (WQv).", "peak_flow_calculation_method": [ "Rational Method (drainage areas up to 200 acres; storm sewer projects up to 640 acres)", "HCFCD H&H Manual methodology (areas greater than 640 acres)", "Clark Unit Hydrograph Method (dynamic hydrograph modeling)", "NRCS Dimensionless Unit Hydrograph (detention volume / static conditions)", "Malcolm's Small Watershed Method (detention volume / static conditions)" ], "required_hydrologic_hydraulic_software": [ "HouStorm" ], "approved_bmp_categories": [ "Bioretention", "Infiltration Trenches", "Porous Pavement / Porous Paver Systems", "Vegetated Swales (dry and wet)", "Green Roof", "Hard Roof", "Rain Barrels", "Detention ponds / stormwater detention basins" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF HOUSTON Stormwater Design and Water Quality Requirements", "page_or_section": "Header / Title, Page 9-0" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Drainage criteria administered by the City of Houston and complemented by Harris County and the Harris County Flood Control District (HCFCD)", "page_or_section": "Section 1, 9.1.02.A, Page 9-2" }, { "field": "document_metadata.state_code", "excerpt": "Infiltration report of soil testing, signed and sealed by a Professional Engineer licensed in the State of Texas", "page_or_section": "Section 1, 9.1.04.O, Page 9-7" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 9 STORMWATER DESIGN AND WATER QUALITY REQUIREMENTS", "page_or_section": "Title Page / Table of Contents, Page 9-0" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Drainage criteria administered by the City of Houston and complemented by Harris County and the Harris County Flood Control District (HCFCD)", "page_or_section": "Section 1, 9.1.02.A, Page 9-2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 9.1 – Rainfall Intensity Coefficients ... 2-year ... 5-year ... 10-year ... 25-year ... 50-year ... 100-year ... 500-year", "page_or_section": "Section 2A, Table 9.1, Page 9-11" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "provides protection from Structural Flooding from a 100-year storm event... The Design Rainfall Event for sizing storm sewers in newly developed areas will be at minimum a 2-year rainfall event.", "page_or_section": "Sections 9.1.02.A and 9.2.01.C.2, Pages 9-2 and 9-14" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "At a minimum, the system must be designed to treat the first 1/2 inch of runoff, except as noted in the SWQGM or the MDC.", "page_or_section": "Section 9, 9.9.01.C.3, Page 9-46" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The layer shall be designed to store at a minimum the water quality volume (WQv).", "page_or_section": "Section 10, 9.10.01.B.3.b.(9), Page 9-51" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational Method: The Rational Method will be used to estimate peak flows for individual drainage areas up to 200 acres in size, and for project areas up to 640 acres in size.", "page_or_section": "Section 2A, 9.2.01.B.2.a, Page 9-12" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Runoff Watershed Modeling: For areas greater than 640 acres, use the methodology specified in the HCFCD H&H Manual.", "page_or_section": "Section 2A, 9.2.01.B.2.b, Page 9-12" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Hydrograph Development Dynamic Conditions – For development of runoff hydrograph for use in dynamic modeling utilize Clark Unit Hydrograph Method. Hydrograph Development Static Conditions – For evaluation of detention volume the approved methodology for hydrograph development shall be based upon the NRCS Dimensionless Unit Hydrograph or Malcolm’s Small Watershed Method.", "page_or_section": "Section 2A, 9.2.01.B.2.c–d, Page 9-12" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HouStorm shall be used to perform 2-year and inlet design analysis and design of storm drainage systems", "page_or_section": "Section 2A, 9.2.01.A, Page 9-10" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HouStorm - The City of Houston’s version of The Texas Department of Transportation’s (TxDOT) software. The program is available from the City.", "page_or_section": "Section 1, 9.1.03.F, Page 9-5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Low Impact Development (LID) techniques that are considered acceptable for achieving detention are Bioretention, Infiltration Trenches, Porous Pavement, Vegetative Swales, Green Roof, Hard Roof, and Rain Barrels.", "page_or_section": "Section 2A, 9.2.01.H.3.j, Page 9-31" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "BMP types include ponds, bio retention facilities, infiltration trenches, grass swales, and filter strips", "page_or_section": "Section 8, 9.8.03.C, Page 9-43" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "permanent stormwater quality BMPs for new development and significant redevelopment must treat the first 1/2 inch of runoff", "page_or_section": "Atlas context / WQv method" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "design the bioretention area to empty within 48 hours", "page_or_section": "9.10.01.B.1.b.(3), page 9-47" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All detention facilities must completely drain out of property within 48 hours", "page_or_section": "9.2.01.H.5.a.(7), page 9-33" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Locate bottom of facility at least 4 feet above seasonal high water table elevation", "page_or_section": "9.10.01.B.2.b.(9), page 9-49" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Depth of ponding limited to a maximum of 6 inches", "page_or_section": "9.10.01.B.1.b.(1), page 9-47" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "6\" MAX PONDED WATER DEPTH", "page_or_section": "Figure 9.7, page 9-66" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The layer must have a minimum depth of nine inches", "page_or_section": "9.10.01.B.3.b.(9), page 9-51" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "In-situ subsoil shall have a minimum infiltration rate of 0.5 inches per hour", "page_or_section": "9.10.01.B.2.b.(1), page 9-48" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rates less than 0.5 inches per hour will require a subsurface drainage system", "page_or_section": "9.10.01.B.1.b.(6), page 9-47" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The layer shall be designed to drain completely in 48 hours", "page_or_section": "9.10.01.B.3.b.(9) Reservoir Layer, page 9-51" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be 2 feet wide minimum or 6 feet wide max", "page_or_section": "9.10.01.B.4.b.(3) Dry Swale, page 9-52" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Chapter 9 (07-01-2022) clearly states City of Houston municipal design criteria, Atlas 14 IDF coefficients for 2–500 year events, Rational/HCFCD/Clark/NRCS/Malcolm hydrology, HouStorm software, first 1/2-inch WQ treatment, and LID BMP list. Complements HCFCD criteria but is an independent city IDM chapter, not a state manual adoption. A 3-year rainfall frequency is defined in 9.1.04.R but has no Table 9.1 intensity coefficients, so it was omitted from the return-period array. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.houstonpermittingcenter.org/media/7596/download?inline=", "landing_page_url": "https://www.houstonpermittingcenter.org/", "retrieved_at": "2026-08-08T10:35:41.196Z", "original_filename": "houston-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 48, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:36:14.892Z", "enrich_model": "composer-2.5:run-371f4425-06c5-44ae-ac52-8b5b5251c7f4", "enrich_notes": "WQv 0.5 in from Atlas context (first 1/2 inch treatment). Infiltration trench SHWT: 4 ft clearance (48 in). Porous pavement reservoir min 9 in; typical 2–4 ft not mapped to a single design number. Swale slope given as 1–6% range only. Green roof: 1 in membrane pond test and 33% storage credit cap; no media depth. Dry/wet swale WQ flow depth <4 in is treatment depth, not bottom width. Private detention must drain within 48 h (9.2.01.H.5.a.(7)).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "huntsville-al", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/huntsville-al/", "data_url": "https://stormwateratlas.com/data/manuals/huntsville-al.json", "document_metadata": { "jurisdiction_name": "City of Huntsville", "jurisdiction_level": "municipality", "state_code": "AL", "document_title": "Low Impact Development Handbook for the State of Alabama (city MS4)", "version_or_edition": "ADEM LID Handbook", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Bioretention and other SCMs sized for the water quality / first-flush volume per ADEM LID Handbook design guidance (same statewide LID framework used for Montgomery).", "peak_flow_calculation_method": [ "ADEM LID Handbook hydrology appendix", "SCM-specific design procedures" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention (BRC)", "Constructed stormwater wetlands (CSW)", "Swales", "Other LID SCMs per handbook" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Huntsville MS4 coverage via ADEM LID Handbook", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Conservation Committee. 2009. Alabama Handbook for Erosion Control, Sediment Control, and Stormwater Management on Construction Sites and Urban Areas. Montgomery, AL. Brown, R.A., W.F. Hunt, and S.G. Kennedy. 2009. Designing Bioretention with an Internal Water Storage (IWS) Lay", "page_or_section": "p. 9" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A BRC is designed to hold approximately the first inch of runoff (first flush) from the entire drainage area.", "page_or_section": "Chapter 4.1 Bioretention, page 36" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Bioretention is normally designed for the water quality or \"first flush\" event, typically the first 1\"-1.5\" of rainfall", "page_or_section": "Chapter 4.1 Bioretention, page 7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "BRCs should completely drain within 48 - 96 hours for the design rainfall volume captured.", "page_or_section": "Chapter 4.1 Bioretention, page 38" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A properly designed BRC will drawdown in <96 hours.", "page_or_section": "Chapter 4.1 Bioretention, page 8" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table is at least 2' from the bottom of the cell", "page_or_section": "Chapter 4.1 Bioretention, page 32" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table should be a minimum of 2' below the permeable pavement base", "page_or_section": "Chapter 4.3 Permeable Pavement, page 80" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Media depths above the underdrain layer must be at least 3' to use IWS", "page_or_section": "Chapter 4.1 Bioretention, page 35" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention Media 36 or pollutant dependent", "page_or_section": "Table 4.1.5, page 40" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding depths should be no more than 12\" for safety reasons.", "page_or_section": "Chapter 4.1 Bioretention, page 36" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "typically ranges from 2 – 4' deep, but can be a minimum of 9\".", "page_or_section": "Chapter 4.3 Permeable Pavement (PC subbase), page 82" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "still retains stormwater within the wetland for a minimum of 48 hours.", "page_or_section": "Chapter 4.2 Constructed Stormwater Wetlands, page 57" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The longitudinal slope should not exceed 5% where possible.", "page_or_section": "Chapter 4.4 Swales, page 94" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable Huntsville city design-manual PDF found (prior 404s); ADEM LID Handbook used as statewide MS4 LID reference.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://adem.alabama.gov/programs/water/waterforms/LIDHandbook.pdf", "landing_page_url": "https://adem.alabama.gov/programs/water/nps/lid.cnt", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "huntsville-al.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 96, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 36, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": 48, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:37:05.581Z", "enrich_model": "composer-2.5:run-e9506105-db53-4c69-abb2-dbf590670af5", "enrich_notes": "Huntsville proxy uses ADEM Alabama LID Handbook. WQ sizing uses Discrete CN Method; BRC surface area tied to ~first inch of runoff with max 12 in ponding. BRC drawdown 48–96 hr (example <96 hr); surface ponding to 2 ft below grade within 48 hr max. CSW temporary pool drawdown target 2–5 days; minimum 48 hr retention in wetland. PP subbase reservoir min 9 in (typical 2–4 ft). No extended detention, green roof design depths, MTD verification, or explicit swale bottom width or L:W ratio in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "independence-mo", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/independence-mo/", "data_url": "https://stormwateratlas.com/data/manuals/independence-mo.json", "document_metadata": { "jurisdiction_name": "City of Independence", "jurisdiction_level": "municipality", "state_code": "MO", "document_title": "MARC/APWA Manual of BMPs for Stormwater Quality + APWA Section 5600 (city adopts both)", "version_or_edition": "MARC/APWA BMP Manual Final October 2012; APWA 5600 adopted", "adoption_or_effective_date": "2012-10-01", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "City Design & Construction Manual adopts APWA Section 5600 Default Strategy: Comprehensive Protection — peak control for 1%, 10%, and 50% chance storms plus volumetric/extended detention of the 90% mean annual event. Water quality via MARC/APWA BMP Manual: WQv captures 90% of average annual runoff using 1.37-inch Water Quality Storm for KC metro (WQv = P × Rv).", "peak_flow_calculation_method": [ "APWA 5600 Default Strategy peak control (1%/10%/50% chance)", "MARC/APWA Short-Cut / Small Storm Hydrology methods", "Rational Method / SCS TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention / rain gardens", "Infiltration trenches", "Permeable pavement", "Extended detention wetland / wet / dry basins", "Sand filters", "Native vegetation swales", "Proprietary MTDs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Independence Engineering Codes list APWA 5600 and MARC & KC APWA BMP Manual", "page_or_section": "City engineering resources page" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Default Strategy: Comprehensive Protection Peak runoff control shall be provided for the 1%, 10% and 50% chance storms and volumetric and/or extended detention control of the 90% mean annual event ... WQv captures 90% ... 1.37-inch Water Quality Storm", "page_or_section": "APWA 5600 city amendments / MARC BMP Manual" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent — metro APWA 5600 + MARC BMP standards", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In the greater Kansas City Metropolitian area, the Water Quality Storm is the 1.37' rain event.", "page_or_section": "Section 3.3 / page 29" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Example: Design a rain garden to treat runoff from the water quality rainfall event for the Kansas City Metropolitan Area (1.37 inches)", "page_or_section": "Section 8.1.7 / page 110" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A cap with an orifice or an in-line orifice fitting shall be provided at or near the discharge point of the underdrain system to permit a 40-hr drawdown time for the WQv.", "page_or_section": "Section 8.4 / page 124" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Capture volume shall be sized to treat the WQv and discharge over a period of 40 hours.", "page_or_section": "Section 8.10.5 / page 212" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "captures the water quality volume (WQv) and releases it over a 40-hour period.", "page_or_section": "Section 8.6.1 / page 147" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "verification that the location of bedrock and the seasonal high groundwater table are not closer than three feet from the sub-grade.", "page_or_section": "Section 8.5.5.1 / page 143" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "A minimum thickness of 12 inches should be used for the aggregate base.", "page_or_section": "Section 8.5.7.4 / page 145" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "being shallower (approximately 18 inches maximum depth in an EDW main pool versus 6 to 12 feet maximum depth in a EWDB main pool).", "page_or_section": "Section 8.6.1 / page 147" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Independence D&C Manual / APWA 5600 only on Issuu (no durable direct PDF); criteria from city-cited MARC BMP Manual + published 5600 amendment excerpts.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.marc.org/sites/default/files/2022-05/Best_Management_Practices_for_Stormwater_Quality.pdf", "landing_page_url": "https://www.independencemo.gov/government/city-departments/community-development/development-services/engineering-codes-standards-and-resources", "retrieved_at": "2026-08-10T09:54:53.517Z", "original_filename": "independence-mo.pdf" }, "design_parameters": { "wqv_depth_inches": 1.37, "max_drawdown_hours": 40, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 18, "ed_drain_time_hours": 40, "length_to_width_ratio": null, "wetland_detention_hours": 40, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:41:05.877Z", "enrich_model": "composer-2.5:run-54760371-af5d-40ee-8445-4cae16cb47c0", "enrich_notes": "KC metro Water Quality Storm is 1.37 inches (WQv captures 90% of average annual runoff). Rain gardens use 12–24 inch amended soil mix and max 6 inch ponding (Section 8.1); bioretention underdrain sized for 40-hour WQv drawdown. Permeable pavement: min 12-inch aggregate base; drawdown design may use 0.5 in/day unless site testing shows higher. EDW permanent pool zones include <6 inch and <18 inch microtopography; EDW main pool max ~18 inches vs EWDB 6–12 ft.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "jackson-ms", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/jackson-ms/", "data_url": "https://stormwateratlas.com/data/manuals/jackson-ms.json", "document_metadata": { "jurisdiction_name": "City of Jackson", "jurisdiction_level": "municipality", "state_code": "MS", "document_title": "MDEQ Volume 2 Stormwater Runoff Management Manual (capital coverage; no standalone city design-manual PDF found)", "version_or_edition": "Published 2011", "adoption_or_effective_date": "2011", "last_revised_date": "2011", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50 ], "water_quality_volume_method": "Capture and treat a water quality volume typically equal to the first 1 inch or first 1.5 inches of rainfall, sized with Schueler's Simple Method (Appendix A). Recommended BMP-specific treatment volumes include: wet detention — first 0.5 inch of runoff or 1.5 inches from impervious area; dry retention and constructed wetlands — first 1.0 inch of runoff or 2.5 inches from impervious area (whichever is greater for dry retention).", "peak_flow_calculation_method": [ "SCS Runoff Curve Number Method", "Short Cut Floodrouting Method (detention storage within method limits)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Planning / site design LID practices", "Infiltration (swales, basins, trenches, permeable pavements)", "Filtration (bioretention, sand/organic filters, vegetated filter strips)", "Retention/Detention (wetlands, dry detention, wet ponds, in-line storage)", "Manufactured stormwater treatment systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Jackson capital coverage via MDEQ Volume 2", "page_or_section": "Coverage note" }, { "field": "document_metadata.document_title", "excerpt": "Volume 2 Stormwater Runoff Management Manual", "page_or_section": "Title Page" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "first 1 inch or first 1.5 inches of rainfall... Schueler's Simple Method", "page_or_section": "MDEQ Vol 2 criteria" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "the peak rate of runoff and volume of runoff increase. These effects are caused by 1) a reduction in the opportunity for infiltration, evaporation, transpiration, and depression storage; 2) an increase in the amount of imperviousness; and 3) modification of the surfac", "page_or_section": "p. 7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration devices must be able to completely dewater within 5 days.", "page_or_section": "Chapter 4 Infiltration, page 4-75 (page 106)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Designers always need to provide significant separation distance (2 to 5 feet) from the bottom of the infiltration basin and the seasonally high groundwater table", "page_or_section": "Chapter 4 Infiltration Basin, page 4-75 (page 106)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "bioretention areas require a minimum depth to groundwater of 2 feet", "page_or_section": "Introduction Table 1-2 discussion, page 1-8 (page 13)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high water table must be at least 2 ft below the base of the permeable pavement or gravel storage layer", "page_or_section": "PICP Design Criteria, page 4-84 (page 115)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "underlying soils must have an infiltration rate of 0.52 inch per hour or greater", "page_or_section": "Infiltration Trench Soils/Topography, page 4-79 (page 110)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Contain areas of standing water for no more than 3 days following a storm event.", "page_or_section": "Dry Retention Systems Additional Criteria, page 4-165 (page 196)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Average flow path through the basin should have a length-to-width ratio of at least 3:1.", "page_or_section": "Dry Retention Systems Additional Criteria, page 4-165 (page 196)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Water shall pond above the cell for a maximum of 12 hours. Water must then drain to a level 24 inches below the surface of the cell within 48 hours (maximum)", "page_or_section": "Bioretention Drainage Considerations, page 4-107 (page 138)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable Jackson city design-manual PDF found; MS4 program page only. Coverage via MDEQ Volume 2 (same pattern as AL capitals with ADEM LID).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.mdeq.ms.gov/wp-content/uploads/2017/05/Volume_2.pdf", "landing_page_url": "https://jacksonms.gov/government/city-departments/public-works-department/stormwater-management/", "retrieved_at": "2026-08-10T09:39:14.788Z", "original_filename": "jackson-ms.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 120, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.52, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:42:06.834Z", "enrich_model": "composer-2.5:run-c75a4bc5-2c73-4303-85a6-0ce17fd171ce", "enrich_notes": "Corpus is MDEQ Vol. 2 (state manual used for Jackson MS coverage). Infiltration dewatering is 5 days; SHWT separation commonly 2 ft minimum (24 in). Infiltration trench minimum soil rate 0.52 in/hr. Dry retention/detention: 3-day max standing water, 3:1 L:W. Bioretention drawdown: 12 h max ponding, 48 h max to drain ponded volume; 2 ft min groundwater for bioretention siting. Swales: 1–2% longitudinal slope recommended, <4%; 2 ft above groundwater for dry/grassed swale. Green roofs: slope limit stated as 20 degrees (not percent). No explicit general WQV depth, bioretention media/ponding depths, permeable base storage depth, or MTD verification program in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "jacksonville-fl", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/jacksonville-fl/", "data_url": "https://stormwateratlas.com/data/manuals/jacksonville-fl.json", "document_metadata": { "jurisdiction_name": "City of Jacksonville", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Land Development Procedures Manual Volume 2", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Wet detention and other stormwater management facilities per LDPM Vol 2; Table 3.7-1 and related criteria. Rational SMF storage for 100-year; SCS for 25-year in specified contexts. MSMP 2070 rainfall depths for 3/5/10/25/50/100-year 24-hour storms.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage: Rational 100-year / SCS 25-year contexts", "Design rainfall depths from MSMP 2070 for multiple return periods" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Jacksonville Land Development Procedures Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Jacksonville", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Land Development Procedures Manual Volume 2", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "effective January 2026", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "January 2026", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Manual Effective January 2026 Page 3 Volume 2: Design Guidelines LAND DEVELOPEMENT PROCEDURE MANUAL REVISIONS Revision Number Sections Revised Effective Date 28 All manual sections reorganized, all of Sections 1, 3, 4 and 7 revised, Appendix 1 Revised, Appendix 3 deleted 07/13", "page_or_section": "p. 3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "in the flood plain. c. In the event a 100-year flood zone, as shown on current FIRM MAPS or delineated by the best available data, is to be filled, 6. Flood-Prone Areas a. Adequate drainage must be provided to accommodate storm water if flood-prone areas are filled. This could", "page_or_section": "p. 76" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "wet detention Table 3.7-1", "page_or_section": "Table 3.7-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational SMF storage 100-year / SCS 25-year", "page_or_section": "SMF design" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "wet detention", "page_or_section": "Table 3.7-1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 / page 109" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3 / page 113" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 / page 125" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: To receive pollutant-load-reduction credits, the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3 / page 109" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 / page 125" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.2 / page 127" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3 / page 109" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3 Sizing / page 112" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Jacksonville LDPM Vol 2 effective Jan 2026. Confirm exact Table 3.7-1 WQ criteria from PDF. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.jacksonville.gov/", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "jacksonville-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:42:43.157Z", "enrich_model": "composer-2.5:run-9ee1324c-85fc-47ce-8576-49e70660ec40", "enrich_notes": "LDPM Vol 2 (Jan 2026) Section 4.3 grassed swales: 72 h recovery, 2–8 ft bottom width (min 2 ft), 0.5–3% longitudinal slope, design infiltration ≤ half field rate (ASTM D3385); SHWL 6 in below swale bottom for WQ credits; BMPTRAINS assumes SHWL ≥24 in below swale bottom. Section 4.4 shallow bioretention: 72 h ponding recovery, SHWL ≥6 in below planting media, ≥0.5 ft below surface ponding area; tributary typically ≤2 ac. Section 4.5 pervious pavement: maintenance if surface rate <1.5 in/hr. Section 3.8 underdrain if groundwater <20 in below gutter/EOP. Wet detention design example uses 1 in and 2.5 in treatment depths and residence time in days—not city Table 3.7-1 WQv in corpus. Pond infiltration design uses safety factor 2 on double-ring tests.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "jefferson-city-mo", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/jefferson-city-mo/", "data_url": "https://stormwateratlas.com/data/manuals/jefferson-city-mo.json", "document_metadata": { "jurisdiction_name": "City of Jefferson City", "jurisdiction_level": "municipality", "state_code": "MO", "document_title": "Missouri Guide to Green Infrastructure (capital MS4 / PUB2446)", "version_or_edition": "PUB2446, May 2012", "adoption_or_effective_date": "2012-05", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Guidance uses water quality rain events occurring roughly 90% of the time (~0.5–1.5 in literature for Missouri), with SCMs designed to infiltrate, evapotranspire, or reuse runoff to the MEP; typical one-inch channel-forming event for energy controls.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Ponds / Extended Wet Detention", "Rain Gardens / Bioretention", "Infiltration Trenches and Basins", "Green Roofs", "Pervious Pavements", "Bioswales / Filter Strips", "Constructed Wetlands", "Stream Buffers" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Jefferson City capital coverage via Missouri Guide to Green Infrastructure", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "water quality volume based on water quality rain events that occur roughly 90% of the time", "page_or_section": "PUB2446" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Dry Detention Basin: any detention facility, vegetated with native plants, designed to permit no permanent impoundment of water but designed to detain the water quality volume for 40 hours.", "page_or_section": "Appendix A, page 238" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Wet Detention Basin: any detention facility designed to include a permanent pool and designed to detain the water quality volume for 40 hours.", "page_or_section": "Appendix A, page 238" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum average depths of 6 to 8 feet help provide long term storage capacity for sediment.", "page_or_section": "Chapter 6, page 211" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Even for those compounds with low contamination potential from surface infiltration, the depth to the groundwater must be considered if it is shallow (1 m or less in a sandy soil).", "page_or_section": "Chapter 5, page 149" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Open water zone: Greater than 18 inches deep... Low marsh zone: 6 to 18 inches deep... High marsh zone: Up to 6 inches deep", "page_or_section": "Chapter 6, page 229" }, { "field": "practice_mentions.bioretention", "excerpt": "Depth of amended soils is critical where specific infiltration volumes are assumed as part of stormwater control measure performance.", "page_or_section": "Chapter 6, page 161-162" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide GI guide — not a full conventional drainage design manual; city may have additional local standards.", "fields_not_found": [] }, "source": { "document_url": "https://dnr.mo.gov/sites/dnr/files/vfc/2023/05/main/pub2446-mo-guide-to-green-infrastructure_1.pdf", "landing_page_url": "https://dnr.mo.gov/document-search/missouri-guide-green-infrastructure-pub2446", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "jefferson-city-mo.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 40, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:43:16.024Z", "enrich_model": "composer-2.5:run-b7e52080-ba63-40f3-bda0-dedf4e6ef01d", "enrich_notes": "Missouri GI guide (PUB2446); glossary defines extended dry/wet detention as detaining water quality volume for 40 hours. Wet pond siting cites 6–8 ft minimum average depth (range, not mapped to single permanent_pool_depth_inches). Constructed wetland zones: open water >18 in, low marsh 6–18 in, high marsh up to 6 in. Infiltration guidance references shallow groundwater ≤1 m (sandy soil) and seasonal high water table limits; no design infiltration rate or SHWT separation in inches. Milwaukee citation: 0.5–1.5 in rains for pollutant mass, not a WQv depth standard in this text.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "jersey-city-nj", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/jersey-city-nj/", "data_url": "https://stormwateratlas.com/data/manuals/jersey-city-nj.json", "document_metadata": { "jurisdiction_name": "City of Jersey City", "jurisdiction_level": "municipality", "state_code": "NJ", "document_title": "Stormwater Management Plan", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Adopts N.J.A.C. 7:8 design and performance standards for stormwater management measures (groundwater recharge, stormwater quality, and quantity), emphasizing nonstructural strategies and green infrastructure before structural BMPs (extended detention, MTDs, etc.). Ordinance Article VI §345-74 implements these standards locally (including 0.6 gal/sf impervious retention for applicable minor development per local practice).", "peak_flow_calculation_method": [ "N.J.A.C. 7:8 runoff quantity standards", "Groundwater recharge standards", "Stormwater quality standards" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Nonstructural / green infrastructure strategies", "Extended detention basins", "Manufactured treatment devices", "NJ BMP Manual practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Jersey City", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "N.J.A.C. 7:8", "page_or_section": "Standards" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Plan", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "design and performance standards for stormwater management measures presented in N.J.A.C 7:8-5", "page_or_section": "Section 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater Management Rules N.J.A.C. 7:8 / groundwater recharge, stormwater quantity, and stormwater quality", "page_or_section": "Introduction / Section 3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "DESIGN AND PERFORMANCE STANDARDS", "page_or_section": "Section 3.0" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Extended Detention Basins / Manufactured Treatment Devices", "page_or_section": "Section 4.3" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the entire volume of a stormwater quality design storm can be drained within 72 hours", "page_or_section": "4.3.1 Bioretention Basins, page 4-6" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the entire runoff volume from the maximum design storm will be drained within 72 hours", "page_or_section": "4.3.3 Dry Wells, page 4-10" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the SHWT is at least 1 foot below the bottom of the bioretention basin's underdrain during non-drought conditions", "page_or_section": "4.3.1 Bioretention Basins, page 4-7" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Extended detention basins are appropriate only when the SHWT is at least one foot below the lowest elevation in the basin", "page_or_section": "4.3.4 Extended Detention Basins, page 4-12" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "the maximum water depth during treatment is 12 inches in a basin and 18 inches in a swale", "page_or_section": "4.3.1 Bioretention Basins, page 4-6" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Stormwater Quality 0.5", "page_or_section": "Table 4-1, page 4-11" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "soil permeability must be greater than 0.5 inches/hour", "page_or_section": "4.3.1 Bioretention Basins, page 4-7" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "narrow basin configurations with length to width ratios from 2:1 to 3:1 should be designed", "page_or_section": "4.3.4 Extended Detention Basins, page 4-12" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "a minimum of 10 percent of the runoff volume generated by the stormwater quality design storm remains in the basin 24 hours after the peak basin water surface", "page_or_section": "4.3.2 Constructed Stormwater Wetlands, page 4-8" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "provided the pollutant removal rates are verified by the New Jersey Corporation for Advanced Technology and certified by the Department", "page_or_section": "Section 6.C Manufactured treatment devices, page 90-91" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipal SWMP adopting NJAC 7:8; numeric sizing primarily in state BMP manual / local ordinance. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level" ] }, "source": { "document_url": "https://jcmua.com/wp-content/uploads/2025/04/Jersey-City-Stormwater-Management-Plan.pdf", "landing_page_url": "https://jcmua.com/", "retrieved_at": "2026-08-10T08:41:07.399Z", "original_filename": "jersey-city-nj.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "New Jersey Corporation for Advanced Technology (NJCAT)", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:43:48.842Z", "enrich_model": "composer-2.5:run-56ce3e3c-4191-4010-8551-1cfdaed26f2c", "enrich_notes": "Numeric sizing for WQv volume defers to NJ Stormwater BMP Manual Chapter 5; local plan summarizes NJ BMP Manual Ch. 9 criteria. Bioretention max ponding 18 in applies to swale configuration per same paragraph. Table 4-1 also lists 0.2 in/hr for groundwater-recharge storm permeability. Dry wells require bottom at least 2 ft (24 in) above SHWT—stricter than 1 ft cited for bioretention underdrain and ED basin invert. ED length:width stated as 2:1 to 3:1. Constructed wetland semi-wet zone uses same 24 h / 10% volume rule as extended detention.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "kennewick-wa", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/kennewick-wa/", "data_url": "https://stormwateratlas.com/data/manuals/kennewick-wa.json", "document_metadata": { "jurisdiction_name": "City of Kennewick", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Management Manual for Eastern Washington (SWMMEW)", "version_or_edition": "July 2024 (Ecology Pub. 24-10-014)", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Ecology SWMMEW Core Element 5 (Runoff Treatment): water quality design storm is the 6-month, 24-hour precipitation computed as Pwqs = Cwqs × P2yr24hr (Cwqs by climate region, Table 4.5). Runoff treatment BMPs sized per Ch.6; infiltration BMPs must infiltrate the 6-month, 24-hour design storm where required. Kennewick is in Eastern Washington — use SWMMEW rather than SWMMWW.", "peak_flow_calculation_method": [ "Core Element 6 Flow Control", "Hydrologic analysis methods in SWMMEW Ch.4", "Runoff treatment and flow control BMP library (Ch.6)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Runoff treatment BMPs (infiltration, biofiltration, wetpool, media filtration)", "Flow control BMPs", "LID BMPs", "Pretreatment BMPs" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Manual for Eastern Washington", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The frequency of the water quality design storm is a 6-month recurrence interval or return period", "page_or_section": "Ch.4 / Equation 4.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Pwqs = Cwqs * P2yr24hr", "page_or_section": "Equation 4.1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum allowable surface pool drawdown time is 72 hours after cessation of flow to the BMP.", "page_or_section": "Chapter 6, Page 597 (BMP F6.23 Bioretention)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "UIC wells are designed to completely drain ponded runoff within 48 to 72 hours after flow to the UIC well has stopped.", "page_or_section": "Chapter 5, Page 362" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of BMP F6.21: Infiltration Ponds or BMP F6.22: Infiltration Trenches shall be ≥ 5 feet above the seasonal high-water mark", "page_or_section": "Chapter 6, Page 538 (SSC-5)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The minimum vertical separation is 5 feet between the base of a UIC well and the highest elevation between the seasonal high groundwater table", "page_or_section": "Chapter 5, Page 362" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The \"Default\" and \"Custom\" BSM depth must be 18 inches to provide Runoff Treatment and good growing conditions", "page_or_section": "Chapter 6, Page 599" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The maximum recommended ponding depth is 12 inches.", "page_or_section": "Chapter 6, Page 597" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "They are not generally appropriate for sites that have a design infiltration rate less than 0.3 inches per hour.", "page_or_section": "Chapter 6, Page 406" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "field testing indicates potential bioretention sites have a measured (a.k.a. initial) native soil saturated hydraulic conductivity less than 0.30 inches per hour.", "page_or_section": "Chapter 6, Page 574" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Regional Ecology SWMMEW used for Kennewick MS4; confirm city adoption ordinance / local amendments.", "fields_not_found": [] }, "source": { "document_url": "https://apps.ecology.wa.gov/publications/documents/2410014.pdf", "landing_page_url": "https://ecology.wa.gov/regulations-permits/guidance-technical-assistance/stormwater-permittee-guidance-resources/stormwater-manuals", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "kennewick-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.3, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:45:45.740Z", "enrich_model": "composer-2.5:run-baee814b-11d2-44ec-a48a-94caa74bc51e", "enrich_notes": "WQv sizing referenced as 6-month 24-hour storm (Chapter 4); no inch depth in excerpts. Bioretention BSM design Ksat 12 in/hr (end-of-life) with safety factor 4 for larger sites. SHWT separation also 36 in (3 ft) with mounding analysis; 12 in for small bioretention/rain gardens; 180 in (15 ft) for deep drywells. UIC ponded drawdown 48–72 hr. Native soil runoff-treatment layer min 18 in (12 in under some permeable pavement). Permeable pavement min slope 1–2%; treatment sand layers 6 in or 12 in. Infiltration swale storage depth typically ≤12 in.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "killeen-tx", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/killeen-tx/", "data_url": "https://stormwateratlas.com/data/manuals/killeen-tx.json", "document_metadata": { "jurisdiction_name": "City of Killeen", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Drainage Design Manual", "version_or_edition": "November 8, 2011 (with later chapter amendments)", "adoption_or_effective_date": "2011-11-08", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "Streets/curbs/inlets/storm sewers designed for 25-year; convey >25-year through 100-year in ROW/easements. Detention: pre-developed 25-year peaks shall not be increased; 100-year passed via emergency spillway without overtopping. Rational / Variable Rainfall Intensity ≤200 ac; SCS for larger.", "peak_flow_calculation_method": [ "Rational Method", "Variable Rainfall Intensity Method (≤200 acres)", "SCS / HEC-HMS methods (larger areas)", "NRCS hydrograph routing for detention ponds" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater detention ponds", "Retention / water quality controls", "Storm sewers and inlets", "Drainage channels" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF KILLEEN DRAINAGE DESIGN MANUAL", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Stormwater runoff peak flow rates for the 25- and 100-year frequency storms ... intercept, contain, and transport all runoff from the 25-year frequency storm", "page_or_section": "§1.2 Drainage Policy" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Pre-developed peak flows generated from the 25-year frequency storm shall not be increased ... 100-year storm event shall be passed from the detention facility through an emergency spillway", "page_or_section": "§1.2.8 Stormwater Detention" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city drainage design manual", "page_or_section": "Coverage note" }, { "field": "practice_mentions.extended_detention", "excerpt": "SWM facilities such as detention, retention, extended detention, infiltration, and sedimentation ponds", "page_or_section": "8.1 GENERAL, page 8-1" }, { "field": "practice_mentions.swale", "excerpt": "Residential lots may drain to a side lot swale or flume only if such feature drains directly to public right-of-way", "page_or_section": "1.2.10 Lot Grading, page 1-10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "No water-quality rainfall or runoff depth (inches) stated; design storms referenced as 25- and 100-year frequency", "page_or_section": "1.2.2 General, page 1-1" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended detention named among pond types; no drain or drawdown time in hours given", "page_or_section": "8.1 GENERAL, page 8-1" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Minimum infiltration rates for the four soils groups are: A 0.30–0.45; B 0.15–0.30; C 0.05–0.15; D 0.00–0.05 (inch/hour)", "page_or_section": "Section 2, Table context page 2-18" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Body PDF; city also posts chapter amendments (2012/2013) that should be consulted for latest policy wording.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.killeentexas.gov/DocumentCenter/View/562", "landing_page_url": "https://killeentexas.gov/303/Mowing-Drainage", "retrieved_at": "2026-08-10T09:54:53.498Z", "original_filename": "killeen-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:47:07.333Z", "enrich_model": "composer-2.5:run-4deea722-5137-4215-aa13-0374ced79523", "enrich_notes": "Corpus is largely drainage policy, hydrology, and partial Ch. 8/9; Section 8.3 SWM pond performance/outlet criteria (TOC 8-2–8-7) is not in excerpts. Peak-control focus: 25-year no peak increase with detention; 100-year via emergency spillway without overtopping. No explicit WQv runoff depth or SCM sizing depths/drawdown times. Table 2-7 soil-group minimum infiltration ranges (in/hr) are for SCS curve numbers, not a stated facility design exfiltration rate. Side-lot swales/flumes allowed with routing limits; trapezoidal vegetated channel min bottom width 4 ft is labeled drainage channel, not swale width. Atlas notes 2012/2013 chapter amendments may supersede wording.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "knoxville-tn", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/knoxville-tn/", "data_url": "https://stormwateratlas.com/data/manuals/knoxville-tn.json", "document_metadata": { "jurisdiction_name": "City of Knoxville", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Best Management Practices (BMP) Manual", "version_or_edition": "January 2018", "adoption_or_effective_date": null, "last_revised_date": "2018-01-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "First flush volume = 0.5 inch of direct runoff over the entire contributing drainage area (min 4,500 cf), released over a minimum of 24 hours (Knoxville Stormwater and Street Ordinance Ch. 22.5). Structural ST BMPs include dry/wet detention, infiltration, wetlands, filter strips/swales, water quality inlets, oil/water separators.", "peak_flow_calculation_method": [ "Detention computations (ST-10)", "HEC-1 / HEC-HMS examples (ST-12)", "Ordinance-defined detention storms (Ch. 22.5)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Dry detention basin", "Wet detention basin", "Infiltration systems", "Constructed wetlands", "Filter strips and swales", "Water quality / media filtration inlets", "Oil / water separator", "Underground detention (special permission)", "Erosion and sediment control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Knoxville", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Knoxville", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Best Management Practices (BMP) Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "January 2018", "page_or_section": "Title page" }, { "field": "document_metadata.last_revised_date", "excerpt": "January 2018", "page_or_section": "Title page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Knoxville Stormwater and Street Ordinance (Chapter 22.5)", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "first flush volume is defined as one-half inch of direct runoff over the entire contributing drainage area", "page_or_section": "Chapter 4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ST-10 Detention Computations; ST-12 Detention Example for HEC-1 and HEC-HMS", "page_or_section": "ST section TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "ST-01 Dry Detention Basin; ST-02 Wet Detention Basin; ST-03 Infiltration Systems", "page_or_section": "ST section" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first flush is defined as a volume equaling the first one-half inch of direct runoff from the entire contributing on-site drainage basin.", "page_or_section": "Chapter 9 glossary, page 77 (knoxville-tn-c0123)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Minimum infiltration storage is generally required to be the first flush volume (the first 0.5\" of stormwater runoff from the entire contributing area).", "page_or_section": "ST-03, page 417 (knoxville-tn-c0424)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown should occur within 72 hours using a safety factor of 2.0 to account for wet-weather water table conditions.", "page_or_section": "ST-03, page 417 (knoxville-tn-c0424)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The first flush volume shall be released slowly over a minimum period of 24 hours, with a maximum drain time of 72 hours", "page_or_section": "ST-10, page 479 (knoxville-tn-c0475)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "An infiltration basin or trench must have at least 3 feet separation from seasonal high groundwater and at least 4 feet separation from bedrock.", "page_or_section": "ST-03, page 417 (knoxville-tn-c0424)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of the infiltration trench should be located at least 3 feet above the seasonal high groundwater table.", "page_or_section": "ST-03, page 422 (knoxville-tn-c0429)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The recommended minimum infiltration rate is at least 0.5 inches per hour", "page_or_section": "ST-03, page 417 (knoxville-tn-c0424)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The allowable infiltration rate is 0.5 inches per hour, although an infiltration rate of 1 inch per hour is highly recommended.", "page_or_section": "ST-03, page 418 (knoxville-tn-c0425)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet detention basin, Permanent pool = 0.5\" per impervious acre", "page_or_section": "Table 4-5, page 42 (knoxville-tn-c0089)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended detention – ... provide for its gradual (attenuated) release over a minimum of 24 hours and no more than 72 hours", "page_or_section": "Chapter 9 glossary, page 77 (knoxville-tn-c0123)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "with a maximum drain time of 72 hours to allow the detention volume to be recovered prior to the next rainfall", "page_or_section": "ST-10 First Flush Release Rate, page 479 (knoxville-tn-c0475)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Combined KnoxvilleBMP.pdf (Jan 2018). First-flush criteria from ordinance citations in manual; peak-rate return periods not fully tabulated in extracted text. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://cdnsm5-hosted.civiclive.com/UserFiles/Servers/Server_109478/File/Engineering/BMPManual/KnoxvilleBMP.pdf", "landing_page_url": "https://www.knoxvilletn.gov/government/city_departments_offices/engineering/engineering_development_services_division/bmp_manual", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "knoxville-tn.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 72, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 0.5, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:48:37.922Z", "enrich_model": "composer-2.5:run-c9e88a1d-9e28-4914-9751-62df34e1bdce", "enrich_notes": "First flush / WQv is 0.5 inch direct runoff (Ch. 9 glossary; ST-03; ordinance per atlas). First-flush release min 24 h, max 72 h (ST-10; extended detention definition). Infiltration: min rate 0.5 in/hr, drawdown within 72 h, 3 ft (36 in) SHWT separation (ST-03). Table 4-5 cites 1 inch held 24 h and 0.5 inch permanent pool per impervious acre for wet detention variants. Knoxville clay limits infiltration applicability. Underground detention ST-08 requires special permission.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lacey-wa", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lacey-wa/", "data_url": "https://stormwateratlas.com/data/manuals/lacey-wa.json", "document_metadata": { "jurisdiction_name": "City of Lacey", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "City of Lacey 2010 Stormwater Design Manual", "version_or_edition": "2010 (Chapters 1–5 excerpt)", "adoption_or_effective_date": "2010", "last_revised_date": null, "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Water Quality Design Storm Volume is the 91st percentile, 24-hour runoff volume calculated using WWHM with Thurston County enhancements (most current version). Water Quality Design Flow Rate is the flow rate at or below which 91% of the runoff volume (WWHM/Thurston) will be treated when preceding detention or when detention is not required; downstream of detention, use the full 2-year release rate from the detention facility. Treatment facility design criteria are assigned to achieve the applicable performance goal at that rate (e.g., 80% TSS removal).", "peak_flow_calculation_method": [ "Western Washington Hydrology Model (WWHM) continuous simulation (default; Thurston County enhancements)", "Calibrated continuous simulation based on EPA HSPF (prior City approval; large/complicated sites)", "Santa Barbara Urban Hydrograph (SBUH)", "NRCS TR-55", "Rational Method (when no hydrologic analysis is otherwise required)" ], "required_hydrologic_hydraulic_software": [ "Western Washington Hydrology Model (WWHM) with Thurston County enhancements / WWHM3", "EPA HSPF (calibrated continuous model; prior approval)" ], "approved_bmp_categories": [ "Construction ESC BMPs (preserving vegetation, buffer zones, seeding/mulching, silt fence, sediment trap/pond, inlet protection, chemical treatment/filtration)", "Runoff conveyance and treatment BMPs (interceptor dike/swale, grass-lined channels, check dams, outlet protection)", "LID site design BMPs (native vegetation, reduce effective impervious, full dispersion)", "Roof downspout controls (infiltration, dispersion, perforated stub-outs)", "Bioretention / permeable paving / vegetated (green) roofs", "Detention ponds, tanks, vaults, and parking lot detention", "Infiltration basins and trenches", "Pre-treatment BMPs (pre-settling basin/wetvault, hydrodynamic devices)", "Biofiltration swales and filter strips", "Wetponds, wetvaults, stormwater treatment wetlands", "Media filtration (sand filters, commercial media filters)", "Oil control (catch basin inserts, oil/water separators)", "Source control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Lacey 2010 Stormwater Design Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "minimum \"Core Requirements\" for development, redevelopment and road projects of all sizes within the City of Lacey", "page_or_section": "Introduction, Page xv" }, { "field": "document_metadata.state_code", "excerpt": "Washington State Department of Ecology Stormwater Management Manual for Western Washington (SMMWW)", "page_or_section": "Introduction, Page xv" }, { "field": "document_metadata.document_title", "excerpt": "City of Lacey 2010 Stormwater Design Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "The City of Lacey 2010 Stormwater Design Manual (SDM) is a completely revised and updated replacement for the 1994 Drainage Design and Erosion Control Manual for Lacey.", "page_or_section": "Introduction, Page xv" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "This manual has been adopted by local ordinance and has force of law.", "page_or_section": "Introduction, Page xvi" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The 2010 SDM is based on the 2005 edition of the Washington State Department of Ecology Stormwater Management Manual for Western Washington (SMMWW). In creating the 2010 SDM, the City of Lacey Department of Public Works has edited and reorganized Ecology's 2005 SMMWW for ease of use and local application.", "page_or_section": "Introduction, Page xv" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "--- page 13 --- List of Tables Table 1.1 Project Review Core Requirements ......................................................... 1-5 Table 1.2 Treatment Requirements by Threshold Discharge Area........................ 1-18 Table 1.3 Flow Control Requirements by", "page_or_section": "p. 13" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The WWHM computes the predevelopment 2- through 100-year flow frequency values and computes the post-development runoff 2- through 100-year flow frequency values from the outlet of the proposed stormwater facility.", "page_or_section": "Chapter 5, Section 5.1.1, Page 5-3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Conveyance systems shall be designed, at a minimum, for the 10-year 24-hour event. Drains and culverts passing under public roads and arterial streets shall be designed for the 25-year event. Culverts for and bridges over natural channels shall be designed to convey the 100-year event.", "page_or_section": "Chapter 5, Section 5.2.1, Page 5-10" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Design Storm Volume: the 91st percentile, 24-hour runoff volume calculated using WWHM with Thurston County enhancements, most current version.", "page_or_section": "Chapter 1, Core Requirement #6, Page 1-18" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The flow rate at or below which 91% of the runoff volume, as estimated by WWHM with Thurston County enhancements, most current version will be treated. Design criteria for treatment facilities are assigned to achieve the applicable performance goal at the water quality design flow rate (e.g., 80% TSS removal).", "page_or_section": "Chapter 1, Core Requirement #6, Page 1-18" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For the purpose of designing runoff treatment and flow control BMPs, the most current version of the Western Washington Hydrology Model (WWHM) with Thurston County enhancements is the standard requirement.... Alternatively, for very large or complicated sites, a calibrated continuous simulation hydrologic model based on the EPA's HSPF... may be used subject to prior approval of the City of Lacey.", "page_or_section": "Chapter 5, Section 5.1, Pages 5-1 to 5-2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Approved single-event methods include Santa Barbara Urban Hydrograph (SBUH) and NRCS TR-55 methods.", "page_or_section": "Chapter 5, Section 5.1, Page 5-2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "If no hydrologic analysis is required for the site, the Rational Method may be used.", "page_or_section": "Chapter 4, BMP C250 Sizing Criteria, Page 4-109" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Runoff and volume calculations shall be provided by the Western Washington Hydrology Model (WWHM) with Thurston County enhancements, most current version. The Thurston County version of the Western Washington Hydrology Model (WWHM3), has been modified to track and compute recharge", "page_or_section": "Chapter 1, Core Requirement #7, Page 1-21" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "WWHM is the default analysis method. The project engineer must obtain pre-approval to use alternative methods.", "page_or_section": "Chapter 5, Page 5-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 6 - Flow Control Design... LID Site Design BMPs... Detention Facilities... Infiltration Facilities... Chapter 7 - Water Quality Treatment... Pre-Treatment BMPs... Biofiltration Facilities... Wetpool Facilities... Media Filtration Treatment BMPs... Oil Control Facilities", "page_or_section": "Table of Contents, Pages v–vii" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "4.3 Standards and Specifications for ESC BMPs... 4.4 Runoff Conveyance and Treatment BMPs... BMP C233: Silt Fence... BMP C240: Sediment Trap... BMP C241: Temporary Sediment Pond", "page_or_section": "Table of Contents, Chapter 4" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool depth of 3 feet is maintained the constructed wetland or wet pond", "page_or_section": "2B-24 Stormwater Treatment checklist (lacey-wa-c0138)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "3 to 1 length to width treatment ratio included", "page_or_section": "2B-24 Stormwater Treatment checklist (lacey-wa-c0138)" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Minimum swale width is 2 feet, maximum swale width is 10 feet", "page_or_section": "2B-24 Stormwater Treatment checklist (lacey-wa-c0138)" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Green Roof — 3-8 inches soil medium; > 8 inches soil medium", "page_or_section": "Table 5.3 LID Techniques Represented in WWHM3, Section 5.1.1 (lacey-wa-c0252)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Source PDF is Chapters 1–5 only; Chapter 6–10 BMP design details appear in the TOC and cross-references but full BMP specification chapters are not in this text extract. Design storms, WQ/WWHM criteria, and hydrologic methods are fully supported in Chapters 1 and 5.", "fields_not_found": [ "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://cityoflacey.org/wp-content/uploads/sites/3/2022/04/2010_lacey_stormwater_design_manual_chapters_1-5.pdf", "landing_page_url": "https://cityoflacey.org/", "retrieved_at": "2026-08-08T10:35:23.259Z", "original_filename": "lacey-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:50:35.553Z", "enrich_model": "composer-2.5:run-e05aa384-a0eb-4bff-9242-cc607ae49d9b", "enrich_notes": "WQv is defined as 91st-percentile 24-hour runoff volume via WWHM/Thurston County, not as a fixed rainfall depth in inches. Infiltration waiver cites native pre-developed soils with infiltration rate less than 0.5 in/hr (Section 1.3 / flow control), not a facility design infiltration rate. Green roof WWHM table lists 3–8 in and >8 in soil medium categories. Treatment swale checklist gives min width 2 ft, max width 10 ft, max flow depth 2 in, max velocity 1.5 fps, flow line slope 1–4%, min flow length 50 ft. Chapters 6–7 BMP numeric specs largely absent from this extract (TOC/forms only).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lafayette-la", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lafayette-la/", "data_url": "https://stormwateratlas.com/data/manuals/lafayette-la.json", "document_metadata": { "jurisdiction_name": "City of Lafayette", "jurisdiction_level": "municipality", "state_code": "LA", "document_title": "Shreveport Drainage Design Manual (LA municipal pattern)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Lafayette city drainage PDF URL 404 from clients. Using Shreveport Drainage Design Manual as Louisiana municipal drainage/stormwater pattern pending a durable Lafayette PDF.", "peak_flow_calculation_method": [ "Municipal drainage design storm criteria", "Detention / conveyance methods per drainage manual" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention / retention", "Storm sewer / open channel conveyance", "Erosion / outlet protection" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Lafayette — coverage via Shreveport Drainage Manual as LA municipal pattern", "page_or_section": "Coverage note" }, { "field": "practice_mentions.extended_detention", "excerpt": "Section 9 Stormwater Detention 9-1 ... 9.3 Minimum Requirements for Detention Basin Design", "page_or_section": "Section 9 / page 6 TOC" }, { "field": "practice_mentions.bioretention", "excerpt": "rain gardens/bioretention", "page_or_section": "Section 11.2 / page 317" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "permeable pavement, green roofs, bioswales/stormwater parks", "page_or_section": "Section 11.2 / page 317" }, { "field": "practice_mentions.green_roof", "excerpt": "permeable pavement, green roofs, bioswales/stormwater parks", "page_or_section": "Section 11.2 / page 317" }, { "field": "practice_mentions.swale", "excerpt": "Inlets can be placed in roadside ditches, grass or lined swales", "page_or_section": "Section 4.4 / page 78" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "subsurface infiltration", "page_or_section": "Section 11.2 / page 317" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder — replace when Lafayette publishes a durable drainage design PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.shreveportla.gov/DocumentCenter/View/29000", "landing_page_url": "https://www.lafayettela.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "lafayette-la.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:51:00.723Z", "enrich_model": "composer-2.5:run-4fec4055-0812-4d17-a3c0-120c3a058b64", "enrich_notes": "Corpus is largely Shreveport Drainage Design Manual (Lafayette proxy): conveyance, hydrology, detention section TOC, and Section 11 GI narrative. No explicit WQv depth, drawdown, SHWT separation, or dimensional SCM design criteria in supplied excerpts; Section 9 body numeric criteria not included.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lakeland-fl", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lakeland-fl/", "data_url": "https://stormwateratlas.com/data/manuals/lakeland-fl.json", "document_metadata": { "jurisdiction_name": "City of Lakeland", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "SWFWMD ERP Applicant's Handbook Volume II (Design Requirements)", "version_or_edition": "Adopted 10-31-25 (AH Vol II with Appendices)", "adoption_or_effective_date": "2025-10-31", "last_revised_date": "2025-10-31", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "SWFWMD ERP AH Vol II stormwater quality and quantity criteria for systems in the District. Open-basin peak discharge typically analyzed with District 24-hour / 25-year rainfall; closed basins may require 24-hour / 100-year volume matching. Treatment volumes and recovery criteria per Parts IV–VI of Volume II (and Volume I performance standards).", "peak_flow_calculation_method": [ "SWFWMD 24-hour / 25-year rainfall maps (open basin)", "24-hour / 100-year volume criteria (closed / volume-sensitive basins)", "NRCS Type II Florida Modified distribution" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems", "Detention systems", "Wet detention", "Off-line treatment systems", "Other SWFWMD-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Lakeland is within SWFWMD and follows ERP AH Volume II", "page_or_section": "Coverage note" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "24-hour, 25-year rainfall maps and the Natural Resources Conservation Service type II Florida Modified 24-hour rainfall distribution", "page_or_section": "SWFWMD AH Vol II §3" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the center line of the perforated pipe", "page_or_section": "4.1.b.2, page 23" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the bottom of the exfiltration pipe", "page_or_section": "4.1.e.3, page 24" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Credit for the PPV is limited to a maximum depth of 8 feet", "page_or_section": "4.1.a.3, page 22" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The total detention volume shall again be available within 36 hours", "page_or_section": "4.1.b.4, page 23" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "sized to discharge ½ inch of detention runoff (mixing volume) from the contributing area in 24 hours", "page_or_section": "4.1.a.3, page 22" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SWFWMD ERP AH Vol II. City portal criteria PDF returned HTML/404 previously.", "fields_not_found": [] }, "source": { "document_url": "https://www.swfwmd.state.fl.us/sites/default/files/medias/documents/SWFWMD%20AHVII%20with%20Appendices-Adopted%20on%2010-31-25.pdf", "landing_page_url": "https://www.swfwmd.state.fl.us/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "lakeland-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 96, "ed_drain_time_hours": 36, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:51:52.202Z", "enrich_model": "composer-2.5:run-1fa8670a-a10b-4adb-90c2-d21acee739ef", "enrich_notes": "Treatment volume sizing references Volume I performance standards (not a fixed WQV depth in these excerpts). Wet detention: PPV max credit 8 ft; mixing drawdown ½ in. in 24 hr; overflow max 10 in. above control. Recovery: 36 hr (detention with effluent filtration), 72 hr (on-line/off-line retention and underground exfiltration; only 36 hr volume counts toward quantity). Exfiltration design rate divided by safety factor 2.0. Pretreatment swale: first ¼ in. runoff, max 4 in. overall depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lancaster-pa-swmf", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lancaster-pa-swmf/", "data_url": "https://stormwateratlas.com/data/manuals/lancaster-pa-swmf.json", "document_metadata": { "jurisdiction_name": "City of Lancaster", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Stormwater Management Fee (SWMF) Policies and Procedures Manual", "version_or_edition": "Amended February 2023 (originally February 27, 2014)", "adoption_or_effective_date": "2014-03-17", "last_revised_date": "2023-02", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "SWMF volume-control / GI credits are available for practices that eliminate stormwater runoff from the site for all storms up to and including a one-inch storm and encourage infiltration (where soils allow) or reuse of captured stormwater. Structural facilities must be consistent with the Pennsylvania Stormwater BMP Manual (PA DEP 363-0300-002). Design sizing for development projects is in the companion Green Infrastructure Design Manual (lancaster-pa) and City Code Chapter 260.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Pervious pavement with infiltration bed", "Rain garden / bioretention", "Dry well / seepage pit", "Subsurface infiltration bed", "Infiltration trench", "Infiltration basin", "Cistern / runoff capture and reuse", "Green roof", "Wet pond / retention basin", "Dry extended detention basin", "Constructed wetland", "Vegetated swale", "Tree trench", "Proprietary water quality filters and hydrodynamic devices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF LANCASTER, PENNSYLVANIA STORMWATER MANAGEMENT FEE (SWMF) POLICIES AND PROCEDURES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "POLICIES AND PROCEDURES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Prepared for City of Lancaster Department of Public Works February 27, 2014 ... Amended February 2023", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Ordinance No. 1-2014 adopted by Lancaster City Council on February 25, 2014 and with an effective date of March 17, 2014", "page_or_section": "Section 1.0 Introduction" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Credits may be available for Best Management Practices (BMP) implemented ... in a manner consistent with the design criteria set forth in the Pennsylvania Stormwater Best Management Practices Manual (PA DEP Document No. 363-0300-002), as amended", "page_or_section": "Section 6.3 Eligible Credit Allowance" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "SWMF credits are available to all properties that implement GI practices which eliminate stormwater runoff from the site for all storms up to and including a one-inch storm and encourages infiltration (where soils are appropriate for infiltration practices), or reuse of captured stormwater.", "page_or_section": "Section 6.5 Structural Credits Calculations" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Amended February 2023 --- page 2 --- Table of Contents Contents 1.0: Introduction .............................................................................................................................. 1 2.0: Definitions and Acronyms ....................................", "page_or_section": "pp. 1–2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "GI practices which eliminate stormwater runoff from the site for all storms up to and including a one-inch storm", "page_or_section": "6.5 Structural Credits Calculations, page 18" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The receiving vegetated area shall be a rectangular shape at least twice as long as it is wide.", "page_or_section": "6.6.2 Downspout Disconnection, page 20" }, { "field": "practice_mentions.bioretention", "excerpt": "Rain Garden (i.e., Bioretention) – an excavated shallow surface depression that consists of a soil bed planted with suitable non-invasive (preferably native) vegetation", "page_or_section": "Definitions, page 9" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roof – an extensive roof cover of vegetation that is grown on and completely covers an otherwise conventional flat or slightly sloped roof (<30° slope)", "page_or_section": "Definitions, page 9" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Pervious Pavement w/ Infiltration Bed – a Green Infrastructure (GI) technique that combines stormwater infiltration, storage, and structural pavement", "page_or_section": "Definitions, page 9" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Proprietary Water Quality Filters and Hydrodynamic Devices – city-approved prefabricated stormwater treatment structures", "page_or_section": "Definitions, page 9; Table 6-2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Fee/credit policy manual (not primary design criteria). Companion design manual is lancaster-pa (Green Infrastructure Design Manual, June 2024). Peak-flow and software fields not specified here.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.cityoflancasterpa.gov/wp-content/uploads/2020/10/SWMF-Policies-and-Procedures-2023.pdf", "landing_page_url": "https://www.cityoflancasterpa.gov/stormwater-information/", "retrieved_at": "2026-08-11T18:45:00.000Z", "original_filename": "SWMF-Policies-and-Procedures-2023.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:52:17.952Z", "enrich_model": "composer-2.5:run-c73d3d76-e796-44af-a75b-1c32d1feb6b5", "enrich_notes": "Fee and credit policy manual; structural facilities must follow PA DEP BMP Manual 363-0300-002. GI volume credits require managing runoff for storms up to and including 1 inch. Design sizing referenced to companion Green Infrastructure Design Manual (lancaster-pa) and City Code Chapter 260—not in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lancaster-pa", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lancaster-pa/", "data_url": "https://stormwateratlas.com/data/manuals/lancaster-pa.json", "document_metadata": { "jurisdiction_name": "City of Lancaster", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "City of Lancaster Green Infrastructure Design Manual", "version_or_edition": "Final June 2024 (Revision 2.0)", "adoption_or_effective_date": "2024-06", "last_revised_date": "2024-06", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "At least the first 1.25 inches of runoff from new impervious surfaces shall be permanently removed (reuse, evaporation, transpiration, and infiltration). Retention volume VRT is the larger of that 1.25-inch volume or the change in runoff volume from the 2-year/24-hour storm.", "peak_flow_calculation_method": [ "NRCS Curve Number Method", "Rational Method", "Modified Rational Method", "WinTR-55 / TR-55", "HEC-HMS" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention/Bioinfiltration", "Porous Pavement", "Green Roofs", "Subsurface Infiltration", "Cisterns", "Naturalized Basins", "Stormwater Wetlands" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Lancaster Green Infrastructure Design Manual", "page_or_section": "Cover / revision history" }, { "field": "document_metadata.document_title", "excerpt": "GREEN INFRASTRUCTURE DESIGN MANUAL Final June 2024", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revisions to support adoption of the City's updated 2022 Stormwater Management Ordinance — October 2023 (draft) June 2024 (final)", "page_or_section": "Revision history" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "At least the first one and a quarter inch (1.25\") of runoff from new impervious surfaces shall be permanently removed from the runoff flow, that is, it shall not be released into the surface Waters of the Commonwealth or Combined Sewer System. Removal options include reuse, evaporation, transpiration and infiltration.", "page_or_section": "Section 2.3.1 Volume Control" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For the 2, 10, 25, 50, and 100-year storm events, the post-development peak discharge rates will follow the applicable release rate map. (SWM Ordinance §260-304.B).", "page_or_section": "Section 2.3.2 Rate Control" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The NRCS Curve Number Method is the preferred method used to estimate site stormwater runoff from a given storm. ... project sites less than 25 acres may be sized for capacity using the Rational Method.", "page_or_section": "Chapter 4 Methodology" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "This includes bioretention, porous pavement, green roofs, cisterns for reuse, naturalized basins and stormwater wetlands.", "page_or_section": "Chapter 3 / Chapter 5 BMP guidance" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" MIN. STORMWATER SOIL", "page_or_section": "Appendix B, BB-2 Typical Stormwater Bumpout" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "12\" MAX. PONDING DEPTH", "page_or_section": "Appendix B, BB-2 Typical Stormwater Bumpout" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Wet basin systems shall be designed with a length-to-width ratio of at least 2:1", "page_or_section": "Section 5.7.1 Components and Design Standards" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Green Roof Area can be considered Disconnected IA with a minimum media depth of 3\" (extensive green roof)", "page_or_section": "Chapter 4, Step 3-E Calculate Green Roof Disconnection (page 55)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Extracted from City of Lancaster GI Design Manual Final June 2024 PDF. Companion fee/credit policy: lancaster-pa-swmf (SWMF Policies and Procedures Manual, amended Feb 2023).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.cityoflancasterpa.gov/wp-content/uploads/2021/01/2024-6-21_Lancaster-SW-Guidance-Manual_FINAL.pdf", "landing_page_url": "https://www.cityoflancasterpa.gov/stormwater-information/green-infrastructure/", "retrieved_at": "2026-08-11T18:15:00.000Z", "original_filename": "2024-6-21_Lancaster-SW-Guidance-Manual_FINAL.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:53:00.987Z", "enrich_model": "composer-2.5:run-43f73d99-dfe7-433f-9bc3-2373dc418d91", "enrich_notes": "Atlas cites 1.25 in retention/VRT policy but that value does not appear in the supplied corpus excerpts. Bioretention numeric standards come from Appendix B BB-2 typical bumpout detail (18 in min stormwater soil, 12 in max ponding). Porous pavement excerpts give product minimum infiltration/flow rates (20 in/hr porous concrete, 5 in/hr paver systems, 45 in/hr joint mortar) rather than a single site design infiltration rate. Post-construction infiltration testing triggers if average exceeds 10 in/hr (Appendix A). Wet basins require minimum 2:1 length-to-width ratio (Section 5.7.1). Green roof disconnection requires minimum 3 in extensive green roof media (Section 4.1 / Equation 4.1-4 context).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lansing-mi", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lansing-mi/", "data_url": "https://stormwateratlas.com/data/manuals/lansing-mi.json", "document_metadata": { "jurisdiction_name": "City of Lansing", "jurisdiction_level": "municipality", "state_code": "MI", "document_title": "Stormwater Management Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 50, 100 ], "water_quality_volume_method": "EGLE-designated Lansing-area water quality treatment volume from 0.9 inches of rainfall (producing storms). Treat by retaining the WQ volume, capturing it in an SCM then filtering/releasing, or filtering continuously. Channel protection applies up to the 2-year 24-hour storm (post ≤ pre volume and peak). Collection system: 10-year 24-hour (non-sag) / 50-year 24-hour (sag).", "peak_flow_calculation_method": [ "Water quality treatment volume (0.9 in)", "Channel protection (2-year 24-hour post ≤ pre)", "Collection system peak (10-/50-year)", "SDST User's Manual example methods" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater control measures (SCMs)", "Retention / infiltration", "Filtration SCMs", "Detention / flood control SCMs", "Bioretention / vegetated practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Lansing Stormwater Management Design Manual", "page_or_section": "Title / cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "producing storms, which for the Lansing area has been designated by EGLE to be 0.9 inches of rainfall", "page_or_section": "Water Quality Treatment Volume" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Channel Protection Up to and including the 2-year 24-hour; Collection System 10-year / 50-year 24-hour", "page_or_section": "Performance criteria table" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Storage facilities are to fully drain the surface water component within 48 hours following a storm event.", "page_or_section": "ENGINEERING STANDARDS – Stormwater Storage, page 18" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The entire cross section should be drained within 72 hours.", "page_or_section": "ENGINEERING STANDARDS – Stormwater Storage, page 18" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Depth from bottom of facility to groundwater table … 2 foot minimum", "page_or_section": "Table 4 Infiltration Facility Design Criteria, page 19" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Depth from bottom of facility to groundwater table … 2 foot minimum", "page_or_section": "Table 5 Detention Pond Design Criteria (Dry Pond; Constructed Wetland), page 20" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil Permeability/Infiltration Rate … 0.5 inches/hr. minimum", "page_or_section": "Table 4 Infiltration Facility Design Criteria, page 19" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Maximum Depth … Wet Pond … 1.5 feet wet depth without safety fencing", "page_or_section": "Table 5 Detention Pond Design Criteria, page 20" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Extracted from Lansing Stormwater Management Design Manual PDF text; truncated tables/layout noise; EGLE 0.9\" WQv is clear.", "fields_not_found": [ "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://content.civicplus.com/api/assets/mi-lansing/5275ad94-2c28-4941-9d23-67842b45023f?cache=1800", "landing_page_url": "https://www.lansingmi.gov/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "lansing-mi.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 18, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:53:44.551Z", "enrich_model": "composer-2.5:run-e4417ede-4468-4751-a1ad-f93670995608", "enrich_notes": "Detailed BMP sizing defers to Michigan LID Manual ch. 6–7; corpus gives Table 4 infiltration and Table 5 pond criteria plus site-wide storage drain times (48 h surface / 72 h full section). Water-quality treatment volume depth (e.g. 0.9 in) referenced via Table 1 but Table 1 text not in excerpts. Infiltration swale bottom width 2–8 ft and bottom slope 1–6% are ranges, not single design numbers.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "laredo-tx", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/laredo-tx/", "data_url": "https://stormwateratlas.com/data/manuals/laredo-tx.json", "document_metadata": { "jurisdiction_name": "City of Laredo", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Water Design Criteria Manual", "version_or_edition": "April 2019", "adoption_or_effective_date": "2019-04", "last_revised_date": "2019-04", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": "null Laredo — city stormwater guidance portal 403; San Antonio drainage criteria as South TX pattern", "peak_flow_calculation_method": [ "Rational Method (Q = CIA) for drainage areas less than 200 acres", "Modified Rational Method for detention ponds with drainage areas of 20 acres or less", "Unit hydrograph method (preferably SCS Dimensionless Unit Hydrograph in HEC-HMS) for drainage areas 200 acres or greater and for detention ponds greater than 20 acres", "Snyder Unit Hydrograph", "Clark Unit Hydrograph", "NOAA Atlas 14 Volume 11 rainfall intensities / depths for San Antonio and ETJ" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS (preferred for SCS Dimensionless Unit Hydrograph / unit hydrograph modeling)" ], "approved_bmp_categories": [ "Onsite detention facilities (Regional Storm Water Management Program option)", "Fee in-lieu-of (FILO) detention participation", "Low Impact Development (LID) planning referenced in manual TOC" ] }, "evidence": [], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "South Texas municipal placeholder using San Antonio criteria — replace with city manual when available. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.sanantonio.gov/Portals/0/Files/CIMS/Services/UDC-Amendment-Drainage-Manual.pdf", "landing_page_url": "https://www.sanantonio.gov/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "laredo-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T10:46:31.952Z", "enrich_model": "composer-2.5:run-53bb2acb-2759-4456-a672-5a55f4138599", "enrich_notes": "Corpus for slug laredo-tx is largely San Antonio Storm Water Design Criteria Manual (April 2019) TOC and intro chapters; preface targets San Antonio/Bexar County drainage, not Laredo-specific BMP sizing. Chapter 13 (Detention Basins, Retention Basins) and spillway table 13.3.2.8 are referenced but numeric SCM/water-quality parameters are not in the supplied excerpts. Checklist cites 5-, 25-, and 100-year storage requirements—not a WQv rainfall depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "las-cruces-nm", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/las-cruces-nm/", "data_url": "https://stormwateratlas.com/data/manuals/las-cruces-nm.json", "document_metadata": { "jurisdiction_name": "City of Las Cruces", "jurisdiction_level": "municipality", "state_code": "NM", "document_title": "Green Infrastructure and Low Impact Design Guide (Albuquerque/Bernalillo — NM municipal reference)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "No durable city design-manual PDF found. Using Albuquerque/Bernalillo GSI/LID Guide as New Mexico municipal green infrastructure reference for volume reduction / LID practices.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure / LID practices", "Infiltration / bioretention", "Harvest and use" ] }, "evidence": [ { "field": "design_parameters.max_drawdown_hours", "excerpt": "Requires permeable soils for infiltration in under 96 hours.", "page_or_section": "Glossary — Infiltration Trench, page 26" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Intended to release water into the soil within 96 hours.", "page_or_section": "Glossary — Passive Rainwater Harvesting, page 26" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of trench should be at least 3' above seasonal high water table", "page_or_section": "Type 2 Infiltration Trench DPM Detail 3.0, page 9" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" minimum depth of planting soil mix, for low plantings only, and 24\" minimum for trees", "page_or_section": "Stormwater Planter Box DPM Detail 8.1, page 16" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" minumum depth shown for planting soil mix for low plantings only, minimum depth for tree plantings should be increased To 24\"", "page_or_section": "Stormwater Curb Extension DPM Detail 5.1, page 11" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Regional NM GI placeholder — replace with city drainage criteria when found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://swefc.unm.edu/gardb/wp-content/uploads/2025/03/61-Green_Infrastructure_and_Low_Impact_Design_Guide_1-1.pdf", "landing_page_url": "https://www.bernco.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "las-cruces-nm.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:55:39.387Z", "enrich_model": "composer-2.5:run-88fe7f9b-c99e-4e0c-804b-0faa5c89493a", "enrich_notes": "Las Cruces proxy uses Albuquerque/Bernalillo GSI/LID Guide. Arid-context glossary prefers bioinfiltration over bioretention; 96-hour drawdown appears for passive harvesting and infiltration trenches. No municipal WQv depth or NJCAT/TAPE programs in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lawrence-ks", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lawrence-ks/", "data_url": "https://stormwateratlas.com/data/manuals/lawrence-ks.json", "document_metadata": { "jurisdiction_name": "City of Lawrence", "jurisdiction_level": "municipality", "state_code": "KS", "document_title": "Stormwater Management Criteria", "version_or_edition": "February 2025", "adoption_or_effective_date": "2025-02", "last_revised_date": "2025-02", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Post-construction BMPs per City's adopted Mid-America Regional Council (MARC) and APWA Manual of Best Management Practices for Stormwater Quality (Sept. 2003 and updates) / Value Rating method. Quantity: detention when required by drainage study; Lake Alvamar watershed example release caps 2-yr 2.4 cfs/acre, 10-yr 3.2 cfs/acre, 100-yr 4.5 cfs/acre. Enclosed minor systems sized for 10-year; major/overflow checked for 100-year.", "peak_flow_calculation_method": [ "Rational Method (≤300 acres / small detention)", "Hydrograph methods for larger basins / detention", "Allowable release rates (Section 9.3)", "MARC/APWA BMP Manual for post-construction quality" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "MARC/APWA structural and non-structural BMPs", "Detention facilities (dry/wet)", "Storm sewer / open channel conveyance", "Parking excess BMPs per MARC manual" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT CRITERIA FEBRUARY 2025", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "City's adopted BMP manual. [Mid-America Regional Council and APWA Manual of Best Management Practices for Stormwater Quality - Sept. 2003 and subsequent updates]", "page_or_section": "Post-construction BMP section" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "2 yr storm 2.4 cfs/acre 10 yr storm 3.2 cfs/acre 100 yr storm 4.5 cfs/acre", "page_or_section": "Section 9.3 / Lake Alvamar criteria" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry Detention Facility: Any detention facility designed to permit no permanent impoundment of water.", "page_or_section": "1.4 Definitions / page 12" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet Detention Facility: A detention facility that is designed to include permanent storage of water in addition to the temporary storage used to control discharge rates from the facility.", "page_or_section": "1.4 Definitions / page 12" }, { "field": "practice_mentions.swale", "excerpt": "All or a portion of the detention storage may also be provided in underground or surface detention areas, including, but not limited to, oversized storm sewers, vaults, tanks, swales, etc.", "page_or_section": "9.8.G Other Detention / page 37" }, { "field": "enrich_notes.parking_lot_detention_depth", "excerpt": "Depths of storage shall be limited to a maximum of seven inches with such areas located so that access to and from parking areas is not impaired.", "page_or_section": "9.8.F Parking Lot Detention / page 37" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://lawrenceks.gov/wp-content/uploads/2025/03/Stormwater-Management-Criteria-2025-1.pdf", "landing_page_url": "https://lawrenceks.gov/mso/technical-resources/", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "lawrence-ks.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:57:09.872Z", "enrich_model": "composer-2.5:run-dfb96856-02d7-4ec3-abbc-cccb35ed53f5", "enrich_notes": "Provided excerpts cover general criteria, hydrology, enclosed systems, improved channels, and Section 9 stormwater detention (quantity). Section 12.0 Post Construction BMPs is listed in the table of contents but its body is not included; atlas context indicates WQv and structural BMP sizing defer to MARC/APWA Manual of Best Management Practices for Stormwater Quality (Sept. 2003 and updates). Parking lot surface detention is capped at 7 inches (Sec. 9.8.F); rooftop detention is allowed with City Engineer approval but no media or drawdown numbers are given.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lincoln-ne", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lincoln-ne/", "data_url": "https://stormwateratlas.com/data/manuals/lincoln-ne.json", "document_metadata": { "jurisdiction_name": "City of Lincoln", "jurisdiction_level": "municipality", "state_code": "NE", "document_title": "Stormwater Post Construction Best Management Practices Guidance Manual", "version_or_edition": "2020 Edition", "adoption_or_effective_date": null, "last_revised_date": "2020", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Post-construction BMPs sized to meet Lincoln Drainage Criteria Manual Chapter 8 / Municipal Code Ch.28.03 post-construction water quality rainfall event (percentile-based depth). Guidance notes most surface pollutants are collected during the first one-half inch of runoff; BMPs (bioretention, native plantings, filters, etc.) selected via matrices for rate, volume, and water quality treatment. Not a substitute for street/stormwater design standards in the Drainage Criteria Manual.", "peak_flow_calculation_method": [ "Lincoln Drainage Criteria Manual hydrology / detention", "BMP selection for rate, volume, and water quality" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Native prairie / vegetation BMPs", "Filter strips / swales", "Permeable pavement / infiltration", "Extended detention / settling practices", "Other Chapter 8 Drainage Criteria Manual BMPs" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Stormwater Post Construction Best Management Practices Guidance Manual City of Lincoln, Nebraska 2020 Edition", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Most surface pollutants are collected during the first one-half", "page_or_section": "BMP guidance narrative" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City of Lincoln Drainage Criteria Manual provides additional information ... Chapter 8 - Stormwater Best Management Practices", "page_or_section": "Introduction" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Water should remain on site for less than 48 hours to prevent mosquito breeding.", "page_or_section": "3.1 Bioretention, page 22" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Another key element of the infiltration basin is having enough area to maintain a shallow pool that will infiltrate within 48 hours or less.", "page_or_section": "3.7 Infiltration Basin, page 52" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Allow 3 ft buffer between bed bottom and seasonal high groundwater table and 2 ft buffer for rock.", "page_or_section": "3.7 Infiltration Basin, page 54" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the swale should be at least three feet above groundwater in order to prevent the swale bottom from remaining too wet.", "page_or_section": "3.5 Grassed Swale, page 43" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Requires soils that allow at least two inches of infiltration per hour.", "page_or_section": "3.8 Infiltration Planter, page 58" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "An underdrain system may be required where soils beneath paving system do not allow adequate infiltration (more than two inches per hour).", "page_or_section": "3.11 Permeable Pavement, page 71" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "The maximum slope for a green roof is about 25 percent.", "page_or_section": "3.6 Green Roof, page 48" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "BMP toolbox manual; exact WQv percentile depth is in Drainage Criteria Manual Ch.8 / Code 28.03 (often chaptered). First-half-inch pollutant narrative is explicit.", "fields_not_found": [] }, "source": { "document_url": "https://www.lincoln.ne.gov/files/sharedassets/public/v/1/ltu/utilities/watershed-management/best-management-practices/bmp-guidelines.pdf", "landing_page_url": "https://www.lincoln.ne.gov/City/Departments/LTU/Utilities/Watershed-Management/Sustainable-Landscapes/Post-Construction-BMPs/Guidance-Manual", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "lincoln-ne.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 25, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:58:22.031Z", "enrich_model": "composer-2.5:run-1c255325-17b6-4cb1-a506-82a5a89708d3", "enrich_notes": "WQv rainfall depth is referenced to City Drainage Criteria Manual Chapter 8 / Municipal Code 28.03, not stated in this BMP toolbox. Rain garden (bioretention-like) gives ponding 4–6 in typical and max 6 in; grassed swale bottom width is 2–8 ft (range only). Infiltration planter standing water up to 12 h; rain garden ponding limit 3 days. Hydrodynamic separators are listed; no third-party MTD verification program named.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "long-beach-ca", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/long-beach-ca/", "data_url": "https://stormwateratlas.com/data/manuals/long-beach-ca.json", "document_metadata": { "jurisdiction_name": "City of Long Beach", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Low Impact Development (LID) Best Management Practices (BMP) Design Manual", "version_or_edition": "2nd edition", "adoption_or_effective_date": "2013-02-19", "last_revised_date": "2013-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "LID BMPs must infiltrate, evapotranspire, and/or capture and use stormwater. Priority for infiltration BMPs. Design to manage the 85th percentile 24-hour runoff event (maximized capture). Implements Long Beach Municipal Code Ch. 18.74 LID ordinance.", "peak_flow_calculation_method": [ "LID volume/flow management via infiltration, ET, capture/use, and flow-rate adjustments", "Treatment control BMPs when on-site retention infeasible" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration BMPs", "Bioretention / biofiltration", "Capture and use", "Evapotranspiration features", "Treatment control BMPs", "Source control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "created by the City of Long Beach Department of Development Services", "page_or_section": "Preface" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Long Beach", "page_or_section": "Preface" }, { "field": "document_metadata.state_code", "excerpt": "Long Beach Municipal Code", "page_or_section": "Preface" }, { "field": "document_metadata.document_title", "excerpt": "Low Impact Development (LID) Best Management Practices (BMP) Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "LID requirements that went into effect on February 19, 2013", "page_or_section": "Preface" }, { "field": "document_metadata.last_revised_date", "excerpt": "revisions that take effect in December 2013", "page_or_section": "Preface" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Chapter 18.74 of the Long Beach Municipal Code", "page_or_section": "Preface" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The 85th percentile 24-hour runoff event determined as the maximized capture", "page_or_section": "Performance criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "storage and retention, infiltration, filtering, and flowrate adjustments", "page_or_section": "LID principles" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "INFILTRATION BMPS", "page_or_section": "Section 4.4" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The volume of runoff produced from a 0.75‐inch storm event.", "page_or_section": "Section 3.1.3 / page 21" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Vdesign (cu ft) = 0.0625 (ft) x Catchment Area (sq ft)", "page_or_section": "Appendix B Calculating Size Requirements / page 81" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The hydraulic conductivity (Ksat) of the subsurface layers is sufficient to ensure the maximum drawdown time of 48 hours.", "page_or_section": "Section 4.4.3 / page 40" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration facilities must be sized to completely infiltrate the design capture volume within 48 hours.", "page_or_section": "Appendix B / page 81" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of five feet of separation to the seasonal (December through April) high ground water level and mounded groundwater level is required.", "page_or_section": "Section 4.2 Groundwater Considerations / page 30" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "biofiltration BMPs shall be constructed with a minimum planting soil depth of 2 feet (3 feet preferred)", "page_or_section": "Section 4.6.3 / page 50" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Media Depth feet 2 (min) 8 (max)", "page_or_section": "Infiltration BMP Design Criteria table / page 82-83" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding Depth inch 18 (maximum)c", "page_or_section": "Infiltration BMP Design Criteria table / page 82" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max Ponding/Flow Depth inch 18", "page_or_section": "Biofiltration BMP Design Criteria / page 87" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "A target long‐term Ksat,media of 5 in/hr is recommended for non‐proprietary amended soil media.", "page_or_section": "Appendix B Biofiltration Step 2 / page 89" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil Media Infiltration Rate in/hr 5 (max)", "page_or_section": "Biofiltration BMP Design Criteria / page 87" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Sediment forebay has a minimum length to width ratio of 2:1", "page_or_section": "Section 4.4.3 / page 40" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall be constructed with a bottom width between 2‐ and 10‐feet.", "page_or_section": "Section 4.6.3 / page 50" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Slope in Flow Direction % … Vegetated Swale … 2% (min) 33% (max)", "page_or_section": "Biofiltration BMP Design Criteria / page 87" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Long Beach LID BMP Design Manual 2nd ed.; primary post-construction WQ/LID criteria. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.waterboards.ca.gov/rwqcb4/water_issues/programs/stormwater/municipal/ms4_permits/long_beach/2014/LIDBMPManual-2ndEd(FINAL)120413.pdf", "landing_page_url": "https://www.longbeach.gov/", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "long-beach-ca.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": 48, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:59:01.822Z", "enrich_model": "composer-2.5:run-48400961-4339-4136-9be4-b217d34ab134", "enrich_notes": "WQV tied to 0.75 in storm and/or 85th-percentile 24-hr volume with 48–72 hr drawdown per WEF/ASCE; infiltration BMPs use 48 hr drawdown and FS 3 (FS 6 if boring only); biofiltration capture is 1.5× WQV with 48 hr surface / 96 hr underdrain drain; capture-and-use may use 72 hr (3 day) drawdown for 0.75 in sizing.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lubbock-tx", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lubbock-tx/", "data_url": "https://stormwateratlas.com/data/manuals/lubbock-tx.json", "document_metadata": { "jurisdiction_name": "City of Lubbock", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Drainage Criteria Manual", "version_or_edition": "November 2019", "adoption_or_effective_date": "2019-11-19", "last_revised_date": "2019-11", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Chapter 9 Stormwater Quality covers post-construction BMPs and structural controls. Primary drainage design emphasizes playa lakes, street/alley conveyance for the 100-year event, and detention/retention (Chapter 7, Modified Rational Method).", "peak_flow_calculation_method": [ "Rational Method (Chapter 3)", "Street hydraulic design / 100-year street capacity analysis", "Playa hydrologic routing and volumetric mitigation (Chapter 5)", "Detention/retention Modified Rational Method (Chapter 7)", "TxDOT IDF coefficients" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Post-construction structural BMPs", "Detention / retention basins", "Playas (overflow and non-overflow)", "Sediment and erosion control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The City of Lubbock, Texas", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Lubbock", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Drainage Criteria Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "is adopted and becomes effective on November 19, 2019. Freese and Nichols, Inc. coordinated the revisions to the 1997 criteria, along with Halff Associates Inc. and Hugo Reed and Associates, Inc. as part of the Stormwater Master Plan update. 1.1 DEFINITIONS The following defi", "page_or_section": "p. 6" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "adopted and becomes effective on November 19, 2019", "page_or_section": "Introduction" }, { "field": "document_metadata.last_revised_date", "excerpt": "is adopted and becomes effective on November 19, 2019. Freese and Nichols, Inc. coordinated the revisions to the 1997 criteria, along with Halff Associates Inc. and Hugo Reed and Associates, Inc. as part of the Stormwater Master Plan update. 1.1 DEFINITIONS The following defi", "page_or_section": "p. 6" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City of Lubbock Drainage Criteria Manual", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-Year Stormwater Capacity Analysis", "page_or_section": "Figure 4.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "9.0 STORMWATER QUALITY / Post-Construction Best Management Practices", "page_or_section": "Chapter 9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational Method / Playa Analysis / Detention and Retention", "page_or_section": "Chapters 3, 5, 7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Structural Controls / Detention/Retention Basin", "page_or_section": "Chapters 7–9" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention Areas — Shallow stormwater basins or landscaped areas which utilize engineered soils and vegetation to capture and treat stormwater runoff.", "page_or_section": "Table 9-1, page 9-2 (lubbock-tx-c0119)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention — May include Dry Detention Basins or Multi-Purpose Detention Areas. Dry Detention Basins are surface facilities intended to provide for the temporary storage of stormwater runoff", "page_or_section": "Table 9-1, page 9-2" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Infiltration Trenches — Excavated trenches filled with stone aggregate used to capture and allow infiltration of stormwater runoff into the surrounding soils", "page_or_section": "Table 9-1, page 9-2" }, { "field": "practice_mentions.sand_filter", "excerpt": "Sand Filters — Multi-chamber structures designed to treat stormwater runoff through filtration, using a sand bed as its primary filter media.", "page_or_section": "Table 9-1, page 9-2" }, { "field": "practice_mentions.swale", "excerpt": "Enhanced Swales — Vegetated open channels that are explicitly designed and constructed to capture and treat stormwater runoff within dry or wet cells formed by check dams or other means.", "page_or_section": "Table 9-1, page 9-2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Lubbock DCM Nov 2019; playa-centric. Confirm Chapter 9 numeric WQ sizing if needed. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.mylubbock.us/DocumentCenter/View/1563/Drainage-Criteria-Manual-PDF", "landing_page_url": "https://www.mylubbock.us/280/Development-Engineering", "retrieved_at": "2026-08-10T08:30:22.061Z", "original_filename": "lubbock-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_trench", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:01:11.731Z", "enrich_model": "composer-2.5:run-3edf844e-259a-4796-a304-579e4e10df06", "enrich_notes": "Chapter 9 Table 9-1 names post-construction structural controls and cites iSWMTM (April 2010, revised September 2014) as source; provided excerpts contain BMP descriptions only, no Lubbock-specific numeric WQ or SCM sizing. Detention includes dry detention and multi-purpose detention; retention basins reference Chapter 6 initial conditions (not in corpus). Playa-centric flood criteria (100-year street depth 12 in., channel min bottom 10 ft) are not mapped to requested SCM parameter keys.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "madison-wi", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/madison-wi/", "data_url": "https://stormwateratlas.com/data/manuals/madison-wi.json", "document_metadata": { "jurisdiction_name": "City of Madison", "jurisdiction_level": "municipality", "state_code": "WI", "document_title": "Madison General Ordinances Chapter 37 — Public Stormwater System including Erosion Control (ORD-25-00017 amendments)", "version_or_edition": "ORD-25-00017 (effective April 1, 2025)", "adoption_or_effective_date": "2025-04-01", "last_revised_date": "2025-03-17", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 100, 500 ], "water_quality_volume_method": "Chapter 37 stormwater management plan requirements include peak detention, infiltration, and TSS control (with enumerated exemptions). Promote infiltration and groundwater recharge. TSS load reduction to maximum extent practicable. Green infrastructure definitions updated.", "peak_flow_calculation_method": [ "Public stormwater system additions generally convey upstream runoff for the 10-year storm event", "Culvert crossings in greenways: 100-year without road overtopping", "Enclosed depressions: convey 100-year (and 25/100-year increases where specified)", "500-year conveyance/overflow route requirements" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure", "Green roofs", "Infiltration basins / underground infiltration fields", "Detention", "TSS control practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Madison General Ordinances", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Madison", "page_or_section": "Ordinance" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 37 of the Madison General Ordinances", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "ORD-25-00017", "page_or_section": "Ordinance" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "These changes will go into effect on April 1, 2025.", "page_or_section": "Drafter analysis / §31" }, { "field": "document_metadata.last_revised_date", "excerpt": "Date: March 17, 2025", "page_or_section": "Ordinance file path" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-year / 100-year / 500-year storm event", "page_or_section": "Design standards" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "peak detention, infiltration and Total Suspended Solids (TSS)", "page_or_section": "Drafter analysis" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "convey the runoff that would drain from upstream lands during the 10-year storm event", "page_or_section": "Design standards" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Green Infrastructure / infiltration basins", "page_or_section": "Definitions / standards" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "using green infrastructure that captures at least the first ½ inch of rainfall over the total site impervious area", "page_or_section": "Sec. 37.09(3)(c)2.k / Page 15" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "using green infrastructure that captures at least the first 1/2 inch of rainfall over the total site impervious area", "page_or_section": "Sec. 37.09(3)(c)3.c / Page 16" }, { "field": "practice_mentions.green_roof", "excerpt": "green roofs, and rain barrels.", "page_or_section": "Sec. 37.04 Definitions / Page 4" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "An extensive green roof with media depth of a minimum of 4\" shall have a runoff CN for this type of feature of 76.", "page_or_section": "Sec. 37.09(3)(c)2.l.ii / Page 15" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "An intensive green roof with a media depth of 12\" shall have a CN of 68.", "page_or_section": "Sec. 37.09(3)(c)2.l.i / Page 15" }, { "field": "practice_mentions.bioretention", "excerpt": "rain gardens, bioretention systems, infiltration basins, underground infiltration fields", "page_or_section": "Sec. 37.04 Green Infrastructure / Page 4" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Pervious/permeable pavement constructed in accordance with WDNR Technical Standard # 1008", "page_or_section": "Sec. 37.04 Impervious Surface note / Page 5" }, { "field": "practice_mentions.swale", "excerpt": "bioswales, permeable pavement, green roofs", "page_or_section": "Sec. 37.04 / Page 4" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "infiltration basins, underground infiltration fields", "page_or_section": "Sec. 37.04 / Page 4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Ordinance amendment PDF rather than standalone design manual; design criteria live in Ch. 37 text. DSC webpage also cites 1–200yr rate control for large new impervious. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://mcclibraryfunctions.azurewebsites.us/api/ordinanceDownload/50000/1346594/pdf", "landing_page_url": "https://www.cityofmadison.com/engineering/stormwater/stormwater-ordinance", "retrieved_at": "2026-08-10T08:18:32.603Z", "original_filename": "madison-wi.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:03:25.384Z", "enrich_model": "composer-2.5:run-5a024e3c-1f9f-45da-ab3d-aa0550633235", "enrich_notes": "Ordinance amendment (MGO Ch. 37); detailed BMP sizing references WDNR construction standards and Dane County Stormwater Manual. Green infrastructure must capture the first 0.5 in over total site impervious (new development and redevelopment). Green roof CN guidance: extensive minimum 4 in media (CN 76), intensive 12 in or more (CN 68). Infiltration: post-development volume at least 90% of pre-development (average annual); optional secondary recharge if >2% site area needed. Rate control uses TR-55 with listed 24-hr design rain depths (1-yr 2.49 in through 500-yr 8.94 in)—not WQv depth. Permeable pavement per WDNR Technical Standard #1008.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "manchester-nh", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/manchester-nh/", "data_url": "https://stormwateratlas.com/data/manuals/manchester-nh.json", "document_metadata": { "jurisdiction_name": "City of Manchester", "jurisdiction_level": "municipality", "state_code": "NH", "document_title": "New Hampshire Model Stormwater Standards / NH Stormwater Manual (city regs)", "version_or_edition": "Draft: May, 2025", "adoption_or_effective_date": null, "last_revised_date": "2025-05", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 50, 100 ], "water_quality_volume_method": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall, Rv = 0.05 + 0.9(I), A = total site area draining to the structure (NH Model Stormwater Standards / NH Stormwater Manual). Manchester Sewer & Stormwater regulations implement NHDES post-construction standards consistent with this manual.", "peak_flow_calculation_method": [ "TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "raingardens", "bioretention systems", "tree box filters", "subsurface gravel wetlands", "filtration practices", "infiltration practices", "swales", "detention areas" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Manchester Stormwater Regulations implement NHDES / NH Stormwater Manual standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall", "page_or_section": "NH Model Stormwater Standards" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = (P)(Rv)(A) P = 1 inch of rainfall", "page_or_section": "Table 1. Stormwater Infrastructure Design Criteria, pages 10-11" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "onsite retention of the first 1-inch of rainfall based on hydrologic soil group (HSG)", "page_or_section": "Element C.2.a, page 4" }, { "field": "practice_mentions.bioretention", "excerpt": "enhanced stormwater SCMs (such as raingardens, bioretention systems, tree box filters, and similar stormwater management landscaping techniques)", "page_or_section": "Element C.1.b, page 3" }, { "field": "practice_mentions.swale", "excerpt": "GIS files containing the coordinates of all stormwater infrastructure elements (e.g. catch basins, swales, detention/bioretention areas, piping)", "page_or_section": "Element D.1.d, page 5" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "subsurface gravel wetlands for water quality treatment is preferred", "page_or_section": "Element C.2.b, page 4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NH Model Stormwater Standards (2025 update). City also posts local Stormwater Regulations PDF.", "fields_not_found": [] }, "source": { "document_url": "https://extension.unh.edu/sites/default/files/media/2025-06/stormwater-management-standards.pdf", "landing_page_url": "https://www.manchesternh.gov/Departments/Sewer-and-Stormwater/Stormwater/Stormwater-Regulations", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "manchester-nh.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:04:20.670Z", "enrich_model": "composer-2.5:run-d0f7bc11-24e4-4c86-9cc2-4fa9ff6a94d3", "enrich_notes": "Manchester adopts NH Model Stormwater Standards (May 2025 draft). WQV uses P=1 inch per Table 1; WPS requires first 1-inch onsite retention by HSG (page 4). SCM sizing references UNH Stormwater Center tool and NH Stormwater Manual for BMP-specific design—not reproduced in these excerpts. GRV recharge depths by HSG (A 0.40, B 0.25, C 0.10, D 0.00 in) are recharge volumes, not WQV depth.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mcallen-tx", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/mcallen-tx/", "data_url": "https://stormwateratlas.com/data/manuals/mcallen-tx.json", "document_metadata": { "jurisdiction_name": "City of McAllen", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Water Design Criteria Manual", "version_or_edition": "April 2019", "adoption_or_effective_date": "2019-04", "last_revised_date": "2019-04", "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": "null McAllen — no durable city PDF; San Antonio South TX pattern", "peak_flow_calculation_method": [ "Rational Method (Q = CIA) for drainage areas less than 200 acres", "Modified Rational Method for detention ponds with drainage areas of 20 acres or less", "Unit hydrograph method (preferably SCS Dimensionless Unit Hydrograph in HEC-HMS) for drainage areas 200 acres or greater and for detention ponds greater than 20 acres", "Snyder Unit Hydrograph", "Clark Unit Hydrograph", "NOAA Atlas 14 Volume 11 rainfall intensities / depths for San Antonio and ETJ" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS (preferred for SCS Dimensionless Unit Hydrograph / unit hydrograph modeling)" ], "approved_bmp_categories": [ "Onsite detention facilities (Regional Storm Water Management Program option)", "Fee in-lieu-of (FILO) detention participation", "Low Impact Development (LID) planning referenced in manual TOC" ] }, "evidence": [], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "South Texas municipal placeholder using San Antonio criteria — replace with city manual when available. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.sanantonio.gov/Portals/0/Files/CIMS/Services/UDC-Amendment-Drainage-Manual.pdf", "landing_page_url": "https://www.sanantonio.gov/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "mcallen-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T09:05:50.304Z", "enrich_model": "composer-2.5:run-a24e526e-4fe6-42af-9a54-b8781a768773", "enrich_notes": "Provided corpus for slug mcallen-tx is largely table-of-contents, San Antonio Storm Water Design Criteria Manual (April 2019) front matter, and hydrology intro; Chapter 13 lists detention and retention basins but excerpt text includes no BMP/LID design numeric criteria. Atlas notes McAllen placeholder using San Antonio South TX pattern with no durable city PDF.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mckinney-tx", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/mckinney-tx/", "data_url": "https://stormwateratlas.com/data/manuals/mckinney-tx.json", "document_metadata": { "jurisdiction_name": "City of McKinney", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Engineering Design Manual", "version_or_edition": "Engineering Design Manual (Rev. — DocumentCenter 16490)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 100 ], "water_quality_volume_method": "Section 4 Stormwater Design Requirements cover detention basins and fully developed 100-year criteria. Section 8 Environmental Design Requirements include Post Construction Stormwater Quality Plan permanent controls and reference iSWM Technical Manual structural control screening.", "peak_flow_calculation_method": [ "Fully developed 100-year design storm / water surface elevation", "5-year and 100-year open-channel flows", "Modified Rational Method detention pond design", "iSWM Technical Manuals referenced for BMPs" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention / retention facilities", "iSWM structural controls / BMPs", "Post-construction stormwater quality permanent controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of McKinney Engineering Department", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of McKinney", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Engineering Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Engineering Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Engineering Design Manual / iSWM Technical Manuals", "page_or_section": "References" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "fully developed 5-year and 100-year flows", "page_or_section": "Section 4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Post Construction Stormwater Quality Plan - Permanent Controls / iSWM Technical Manual", "page_or_section": "Section 8.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Modified Rational Method Detention Pond Design", "page_or_section": "Section 4.10 / figures" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Refer to the Rights-of-Way Management Ordinance (Section 90) and Rights-of-Way Construction and Permitting Procedures Manual available online at mckinneytexas.org. Contact the Public Works Department regarding ROW permits at row@mckinneytexas.org or (972)547-1033. ER", "page_or_section": "p. 279" }, { "field": "practice_mentions.bioretention", "excerpt": "1. Bioretention Area- maintenance as listed in iSWM revision 2014", "page_or_section": "Appendix B PCSWQP Checklist 2, page 270" }, { "field": "practice_mentions.swale", "excerpt": "2. Enhanced Swale- maintenance as listed iSWM Revised 2014", "page_or_section": "Appendix B PCSWQP Checklist 2, page 270" }, { "field": "practice_mentions.swale", "excerpt": "Drainage System – Includes streets, alleys, storm drains, drainage channels, culverts, bridges, overflow swales, and any other facility", "page_or_section": "Appendix A A-4, page 254" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Large EDM; adoption date unclear on title page; confirm which Rev is effective vs Proposed Rev 6. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.mckinneytexas.org/DocumentCenter/View/16490/McKinney-Engineering-Design-Manual---Proposed-Rev-6-20241119", "landing_page_url": "https://www.mckinneytexas.org/1507/Engineering-Resources---Forms-Notes", "retrieved_at": "2026-08-10T08:45:22.876Z", "original_filename": "mckinney-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "swale" ], "enriched_at": "2026-08-13T09:06:12.051Z", "enrich_model": "composer-2.5:run-827292a6-489c-4da6-8329-2316d948d3e1", "enrich_notes": "Provided excerpts are Appendix A definitions, Appendix B checklists, and Appendix C general notes. PCSWQP checklist names Bioretention Area and Enhanced Swale with maintenance per iSWM Revised 2014; no numeric BMP sizing, WQv depth, drawdown, or infiltration criteria appear in this corpus. Atlas cites Section 4 detention and Section 8 PCSWQP/iSWM screening—not included in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "melbourne-fl", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/melbourne-fl/", "data_url": "https://stormwateratlas.com/data/manuals/melbourne-fl.json", "document_metadata": { "jurisdiction_name": "City of Melbourne", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Jacksonville Land Development Procedures Manual Volume 2 (SJRWMD-region municipal pattern)", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "SJRWMD ERP AH Vol II PDF not publicly fetchable (403). Using Jacksonville LDPM Vol 2 wet detention / SMF pattern as east-central Florida municipal reference: wet detention and stormwater management facilities per Table 3.7-1; MSMP 2070 rainfall depths for multi-return-period 24-hour storms. Prefer SJRWMD AH Vol II when a durable PDF is available.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage contexts", "Design rainfall depths from MSMP 2070" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Melbourne (SJRWMD) — coverage via Jacksonville LDPM Vol 2 pattern", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treatment Volume 1-inch runoff: TV = (10 ac x 1 inch) / 12 = 0.83 acre-feet", "page_or_section": "Section 4.3 Design Example / page 118 (LDPM Vol 2)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 Grassed Conveyance Swales / page 105" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3 Recovery Requirements / page 110" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 Shallow Bioretention / page 121" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: To receive pollutant-load-reduction credits, the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3 / page 105" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 Shallow Bioretention / page 121" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.1 Physical Constraints / page 123" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3 Design Criteria / page 105" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3 Sizing Requirements / page 108" }, { "field": "practice_mentions.swale", "excerpt": "Longitudinal slope between 0.5 percent and 3 percent.", "page_or_section": "Section 4.3 Design Criteria / page 105" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "If the pervious pavement system infiltration rates measured using the installed testing device are less than 1.5 inches per hour, maintenance must be performed", "page_or_section": "Section 4.5 Maintenance Requirements / page 136" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Canonical SJRWMD special_district record: fl-sjrwmd-erp-ah2. Placeholder pending durable SJRWMD AH Vol II or city design-manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.sjrwmd.com/documents/permitting/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "melbourne-fl.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:08:02.089Z", "enrich_model": "composer-2.5:run-c87c8733-c7c9-4e53-89aa-b121495d7169", "enrich_notes": "Corpus is Jacksonville LDPM Vol 2 (Jan 2026) as east-central FL municipal proxy for Melbourne; SJRWMD 3-year/1-hour storm and net-improvement framing appear in swale/wet-detention examples. Swale longitudinal slope is explicitly 0.5–3% (no single design value). Bioretention SHWL also stated as 0.5 ft below surface ponding area (6 in). Pervious pavement maintenance threshold 1.5 in/hr surface infiltration; Figure 4.5-4 references SHWL within 24 in of reservoir bottom for capture modeling. Basin infiltration design uses safety factor of 2 on double-ring infiltrometer (Section 3.7). Green roof listed as LID strategy only—no numeric roof criteria in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "memphis-tn", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/memphis-tn/", "data_url": "https://stormwateratlas.com/data/manuals/memphis-tn.json", "document_metadata": { "jurisdiction_name": "City of Memphis and Shelby County", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Storm Water Management Manual Volume 1: Policies and Procedures", "version_or_edition": "Volume 1", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Water quality BMPs are encouraged but not required under Volume 1 policy; stormwater management (detention) is mandatory. Detailed hydrologic methods and BMP design are in Volumes 2–3.", "peak_flow_calculation_method": [ "Detention required for new development and significant redevelopment", "10-year storm defines active drainage path capacity context", "100-year floodplain / flood management definitions apply" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention", "Water quality BMPs (encouraged)", "Erosion and sediment control measures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Memphis and Shelby County Storm Water Management Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Memphis and Shelby County", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Volume 1 Policies and Procedures", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Storm Water Management Manual Volume 1", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "water with expected flows for the 10-year 24-hour storm event. The active path should be kept in pipes, ditches and streets. 2. Flood, flooded or flooding: A temporary condition of partial or complete inundation of normally dry land from the overflow of a watercourse. 3. Fl", "page_or_section": "p. 40" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "water quality BMPs are encouraged but not required", "page_or_section": "Policy" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "this manual. 2.4 Storm Water Quantity Detention Increased urbanization within Memphis and Shelby County has caused radical changes to the topography, ground cover, and minor storm water management systems within each drainage basin. These changes have adverse effects on the env", "page_or_section": "p. 28" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "detention / water quality BMPs", "page_or_section": "Policy" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Detention storage volume necessary to meet the requirements of the two preceeding subsections shall be drained within 72 hours.", "page_or_section": "6.6.4 Drawdown; Page 6-14" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio of at least 4:1", "page_or_section": "6.7.2 Dry and Wet Detention Design Criteria; Page 6-18" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Maximum permanent pool depth of no more than 12 feet unless recirculated with an aerator or fountain", "page_or_section": "6.7.2 Dry and Wet Detention Design Criteria; Page 6-18" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Bleed down or \"live\" storage volume of the first 0.5 to 1.0 inches of runoff", "page_or_section": "6.7.2 Dry and Wet Detention Design Criteria; Page 6-18" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "residence time of 12 to 24 hours for dry ponds and 24 to 60 hours for wet ponds", "page_or_section": "6.7.2 Dry and Wet Detention Design Criteria; Page 6-18" }, { "field": "practice_mentions.swale", "excerpt": "grass swales may be utilized; however, they must be approved by the city or county engineer", "page_or_section": "6.1.3.1 Street Drainage Improvements; Page 6-5" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "In-ground pre-manufactured water quality units will be evaluated on a case-by-case basis", "page_or_section": "7.1.2.5 PCRC Plan Review Information; Page 7-4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Volume 1 is policy-only. Volumes 2–3 contain methods and BMP design criteria; extract those next for fuller WQ/peak methods. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.shelbycountytn.gov/DocumentCenter/View/34048/Volume-1-Policy-Manual", "landing_page_url": "https://www.shelbycountytn.gov/", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "memphis-tn.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 144, "ed_drain_time_hours": null, "length_to_width_ratio": 4, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:08:16.738Z", "enrich_model": "composer-2.5:run-727e3ee1-ba52-43ed-b80c-a4c60511dc36", "enrich_notes": "Volume 1 policy only; WQ BMPs encouraged not required. WQ dry/wet detention cites bleed-down of first 0.5–1.0 in runoff with residence 12–24 h (dry) and 24–60 h (wet)—ranges not mapped to single canonical fields. Detention quantity drawdown is 72 h (Section 6.6.4). Permanent pool max 12 ft (144 in). Length:width at least 4:1 for WQ dry/wet detention. BMP design detail deferred to Volumes 2–3.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mesa-az", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/mesa-az/", "data_url": "https://stormwateratlas.com/data/manuals/mesa-az.json", "document_metadata": { "jurisdiction_name": "City of Mesa", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Engineering & Design Standards", "version_or_edition": "2022", "adoption_or_effective_date": null, "last_revised_date": "2022", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Chapter 8 Storm Water Drainage & Retention: on-site stormwater management and retention basin requirements. LID landscape guidance in Section 1112. Mesa LID Toolkit referenced as guideline.", "peak_flow_calculation_method": [ "On-site storm water management per Section 806", "Street drainage and off-site storm water management per Section 807", "Developed-condition runoff C coefficients by storm frequency (Table 8.1)", "Public and private retention basins (Sections 808–809)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention basins", "Storm drains", "Low Impact Development (LID) landscape features" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Mesa Engineering Department", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Mesa", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "City of Mesa", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Engineering & Design Standards", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Engineering & Design Standards", "page_or_section": "Purpose" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Section 806 - On-Site Storm Water Management", "page_or_section": "Chapter 8" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Table 8.1 - Developed Condition Runoff (C) Coefficients by Storm Frequency", "page_or_section": "Chapter 8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Basins / Low Impact Development (LID) Landscape", "page_or_section": "Sections 808 / 1112" }, { "field": "practice_mentions.bioretention", "excerpt": "Suggested “tools” highlighted in the toolkit include: Green Streets, Vegetated Swales, Bioretention, Permeable Paving, Constructed Wetlands, Infiltration & Underdrains, Green Roofs, Rainwater Harvesting.", "page_or_section": "Section 1112, page 211" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated Swales", "page_or_section": "Section 1112.2, page 211" }, { "field": "enrich_notes (drywell infiltration, not mapped to in/hr field)", "excerpt": "Such drywells shall have a minimum infiltration rate after de-rating of 0.1 cfs", "page_or_section": "806.21.2.6, page 152" }, { "field": "enrich_notes (drawdown time unspecified)", "excerpt": "If the infiltrometer tests and associated calculations do not demonstrate that direct percolation can drain the storage system within the required time, other means of disposal shall be installed", "page_or_section": "806.21.2.5, page 152" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Mesa EDS 2022 Ch 8; confirm retention depth/volume numeric criteria from Section 806 tables. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.mesaaz.gov/files/assets/public/v/1/business-development/engineering/designstandards/2022engdesignstandards.pdf", "landing_page_url": "https://www.mesaaz.gov/business-development/engineering", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "mesa-az.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:08:43.878Z", "enrich_model": "composer-2.5:run-d503a5fb-1245-46b2-b4d3-bef2869f462f", "enrich_notes": "Corpus includes Ch. 8 §806.21.2 direct percolation and drywell supplement (0.1 cfs de-rated minimum for dual-chamber drywells; ADEQ 100-ft setback from groundwater wells) but not Section 806 retention depth/volume tables cited in Atlas. LID numeric criteria deferred to external Mesa LID Toolkit per §1112.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mesquite-tx", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/mesquite-tx/", "data_url": "https://stormwateratlas.com/data/manuals/mesquite-tx.json", "document_metadata": { "jurisdiction_name": "City of Mesquite", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Engineering Design Manual — Section 3 Drainage Design Requirements", "version_or_edition": "Engineering Design Manual Sections 1–9", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "Table 3-1: enclosed storm drains/inlets, roadside ditches, streets, culverts, channels, and detention/retention sized for 100-year (staged outlet for basins). Pedestrian bridges 25-year. Hydrology: Rational ≤200 ac; unit hydrograph / NCTCOG iSWM Hydrology Technical Manual for larger areas. Detention may be required per §3.9 / downstream assessment.", "peak_flow_calculation_method": [ "Rational Method (≤200 acres)", "NCTCOG iSWM Hydrology Technical Manual / unit hydrograph methods", "Detention and retention facility design (§3.9)", "Downstream assessments (§3.10)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Enclosed storm drain systems", "Open channels", "Detention / retention facilities", "Best Management Practices (maintenance plans required)", "Erosion and sediment controls (§3.11)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Engineering Design Manual of the City of Mesquite, Texas", "page_or_section": "§1.1" }, { "field": "document_metadata.document_title", "excerpt": "SECTION 3 DRAINAGE DESIGN REQUIREMENTS", "page_or_section": "§3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 3-1 ... Enclosed Storm Drain Systems and Inlets 100-year ... Detention and Retention Basins 100-year", "page_or_section": "Table 3-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "current edition of the NCTCOG Integrated Stormwater Management (iSWM™) Hydrology Technical Manual", "page_or_section": "§3.2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city engineering design manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "All earthen drainage swales draining areas less than one cumulative acre shall have a 2% minimum slope. ... All paved drainage swales shall have a 1% minimum slope.", "page_or_section": "Section 3.1.14, Drainage Design Requirements 3-3 (mesquite-tx-c0065)" }, { "field": "practice_mentions.swale", "excerpt": "Drop inlets shall only be located to collect water on non-paved areas where it is not practical to use a headwall, such as swales.", "page_or_section": "Section 3.4, Drainage Design Requirements 3-18 (mesquite-tx-c0078)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention Basin – A dry basin or depression constructed to temporarily store stormwater runoff and discharge the water over time at a reduced rate than would have otherwise occurred.", "page_or_section": "Section 9 Definitions, 9-2 (mesquite-tx-c0171)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention/Retention Facilities and Levees – An easement must encompass the entire facility plus 15 feet on all sides measured from the top of bank.", "page_or_section": "Section 1.8.8.E, General Design Requirements 1-8 (mesquite-tx-c0008)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Full EDM Sections 1–9 PDF; drainage criteria concentrated in §3. Edition date not clear on extract.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.cityofmesquite.com/DocumentCenter/View/13132", "landing_page_url": "https://www.cityofmesquite.com/2065/Engineering-Design-Manual", "retrieved_at": "2026-08-10T09:54:53.503Z", "original_filename": "mesquite-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T09:09:12.015Z", "enrich_model": "composer-2.5:run-746b3e8f-8410-46d1-9444-9868430b5fb0", "enrich_notes": "Provided excerpts are mostly Section 1, roadway (Section 2), partial Section 3 (lot grading, inlets, open channels, erosion BMPs §3.11), utilities, and definitions—not Table 3-1 design storms or detailed SCM sizing. Swale grading: earthen drainage swales under 1 ac require 2% minimum longitudinal slope; paved drainage swales 1%; side/back yards 1%. No WQv depth, infiltration rates, drawdown times, or bioretention/permeable/green-roof/wetland/manufactured-treatment design numbers in corpus. Detention/retention referenced for easements and as approved facility type; Detention Basin defined as dry temporary storage with delayed release.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "miami-fl", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/miami-fl/", "data_url": "https://stormwateratlas.com/data/manuals/miami-fl.json", "document_metadata": { "jurisdiction_name": "City of Miami / Miami-Dade (SFWMD criteria)", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II For Use Within the Geographic Limits of the South Florida Water Management District", "version_or_edition": "AH Vol. II (6/28/24)", "adoption_or_effective_date": "2024-06-28", "last_revised_date": "2024-06-28", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 25, 100 ], "water_quality_volume_method": "Water quality treatment volumes and pollutant load-reduction requirements are set forth in ERP Applicant's Handbook Volume I; Volume II adds SFWMD-specific retention/detention criteria (e.g., commercial/industrial projects provide a minimum of 20% of the AH Vol. I load reduction in a retention BMP; exfiltration trenches sized for AH Vol. I water quality requirements exfiltrated over one hour prior to overflow; treatment volume in retention/exfiltration systems is not discharged to surface waters).", "peak_flow_calculation_method": [ "Pre- and post-development runoff hydrographs with detention routing (stage-storage-discharge)", "SCS Peak Rate Factor (K') method", "NRCS National Engineering Handbook Section 4, Part 630, Chapter 10 (peak factors)", "Rational method (for water quality retention/detention)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems (depressional areas, shallow landscaped areas, vegetated swales)", "Dry retention/detention", "Wet detention", "Exfiltration trench (underground)", "Above Ground Impoundment (AGI)", "Grassed waterways / spreader swales" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "FOR USE WITHIN THE GEOGRAPHIC LIMITS OF THE SOUTH FLORIDA WATER MANAGEMENT DISTRICT", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_name", "excerpt": "Within Miami-Dade County, an ERP is not required for the construction, alteration, or operation of a SWM system in uplands provided that the system meets all the conditions below", "page_or_section": "Section 1.2 District-Specific Thresholds" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Within Miami-Dade County, an ERP is not required for the construction, alteration, or operation of a SWM system in uplands", "page_or_section": "Section 1.2" }, { "field": "document_metadata.state_code", "excerpt": "South Florida Water Management District Clerk's Office, 3301 Gun Club Road, West Palm Beach, FL 33406", "page_or_section": "Section 4.1.1 / references" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II FOR USE WITHIN THE GEOGRAPHIC LIMITS OF THE SOUTH FLORIDA WATER MANAGEMENT DISTRICT", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "AH VOL. II (6/28/24)", "page_or_section": "Header / Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE JUNE 28, 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "EFFECTIVE JUNE 28, 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Volume provides specific, detailed stormwater quality and quantity design and performance criteria for SWM systems regulated by the District through the ERP program authorized under Part IV of Chapter 373, F.S.", "page_or_section": "Section 1.0 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Unless otherwise specified by previous Agency permits, criteria, or Appendix A to this Volume, a 25-year, 3-day storm event shall be used in computing off-site discharge rates.", "page_or_section": "Section 3.2 Design Storm" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Building floors shall be at or above the 100-year flood elevations... Both tidal flooding and the 100-year, 3-day storm event shall be considered in determining elevations.", "page_or_section": "Section 3.3 Flood Protection of Building Floors" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Road crown: Frequency: 5-year... Parking lots: Frequency: 5-year", "page_or_section": "Section 3.4 Flood Protection of Roads and Parking Lots" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Commercial or industrial zoned projects shall provide a minimum of 20% of the load reduction required by AH Vol. I in a retention BMP or a separate containment system designed to prevent discharge.", "page_or_section": "Section 4.1.1 Land Use and Coverage Criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Systems shall be designed for the water quality requirements set forth in AH Vol. I, exfiltrated over one hour for retention purposes, prior to overflow, and based on test data for the site.", "page_or_section": "Section 4.3 Underground Exfiltration Trench Systems" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Unlike detention basins, the treatment volume for retention systems is not discharged to surface waters.", "page_or_section": "Section 5.2.1 Retention System Description" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "An acceptable historic peak discharge analysis typically consists of generating pre-development and post-development runoff hydrographs, routing the post-development hydrograph through a detention basin, and sizing an overflow structure to control post-development discharges at or below pre-development rates.", "page_or_section": "Section 3.2.1 Methodologies" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Historic peak discharge calculations must make proper use of the SCS Peak Rate Factor or K' Factor.", "page_or_section": "Section 3.2.1 Methodologies" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The usual methods of computation are as follows: (a) Rainfall minus losses and storage. (b) U.S. Department of Agriculture, Natural Resources Conservation Service, \"National Engineering Handbook, Section 4, Part 630, Chapter 10 – 2004.\" ... (c) Rational method, for water quality retention/detention purposes.", "page_or_section": "Section 5.6.6 Runoff" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Examples of retention systems include: (a) Man-made or natural depressional areas... (b) Shallow landscaped areas designed to store stormwater; and (c) Vegetated swales with swale blocks or raised inlets.", "page_or_section": "Section 5.2.1 Retention System" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wet detention systems... Dry retention/detention areas... Exfiltration trench systems", "page_or_section": "Sections 5.2.3, 5.3, 5.5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "\"Above Ground Impoundment (AGI)\" – a type of dam... Appendix B AGIs... Appendix C Exfiltration System Trench Design", "page_or_section": "Section 2.1.1; Appendices" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "In an exfiltration trench system, stormwater shall pass through a perforated pipe and infiltrate through the trench walls and bottom into the shallow groundwater aquifer", "page_or_section": "5.5.1 Description, page 31" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.2 Retention System, page 28" }, { "field": "practice_mentions.wet_pond", "excerpt": "\"Wet detention systems\" – Permanently wet ponds which are designed to slowly release collected stormwater runoff through an outlet structure.", "page_or_section": "2.1.17, page 8" }, { "field": "practice_mentions.extended_detention", "excerpt": "\"Retention/detention area (dry)\" – Water storage area with bottom elevation at least 1.0-feet above the control elevation of the area.", "page_or_section": "2.1.13, page 8" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Man-made or natural depressional areas where the basin bottom is graded flat and vegetation is established to promote infiltration", "page_or_section": "5.2 Retention System, page 28" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Municipal map coverage via SFWMD ERP AH Vol II. Canonical special_district record: fl-sfwmd-erp-ah2. Previously mislabeled as county; reclassified to municipality proxy. Regional SFWMD ERP Applicant's Handbook Vol II (not a Miami city-only ordinance). Jurisdiction coded as county per task guidance to reflect Miami-Dade regional coverage; SFWMD is a water management district. Numeric WQ treatment depths live primarily in AH Vol. I (referenced throughout Vol. II).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/swerp_applicants_handbook_vol_ii.pdf", "landing_page_url": "https://www.sfwmd.gov/", "retrieved_at": "2026-08-08T10:41:40.344Z", "original_filename": "miami-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:10:18.471Z", "enrich_model": "composer-2.5:run-2c65a75b-34f8-41da-9ae2-4c04f610bb0d", "enrich_notes": "SFWMD ERP Applicant's Handbook Volume II (6/28/24); water-quality treatment volumes and rainfall depths are referenced to Volume I, not stated as wqv_depth_inches in these excerpts. Residential Section 3.8(a) requires discharge/percolation of at least 0.375 inches per day and lowering of SWM water surfaces within 12 days (not mapped to max_drawdown_hours without inferring). Parking lots with exfiltration trenches use 5-year, 1-hour storm duration for flood protection (Section 3.4), not exfiltration drawdown time. Exfiltration trenches: 12-inch min pipe, 3-foot min trench width (Section 5.5.2); treatment volume must percolate within a specified time but no hour value in provided text. Dry vs wet retention/detention defined by bottom elevation relative to control (+1.0 ft dry per Section 2.1.13–2.1.14).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "minneapolis-mn", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/minneapolis-mn/", "data_url": "https://stormwateratlas.com/data/manuals/minneapolis-mn.json", "document_metadata": { "jurisdiction_name": "City of Minneapolis", "jurisdiction_level": "municipality", "state_code": "MN", "document_title": "Stormwater and Sanitary Sewer Guide", "version_or_edition": "October 2017, Revision #2: February 2025", "adoption_or_effective_date": "2017-10", "last_revised_date": "2025-02", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Rate control: no increase in peak discharge over existing for 2-, 10-, and 100-year 24-hour events (NRCS MN MSE 3 distribution). Water quality: 70% TSS removal from a 1.25-inch storm event, plus receiving-water-specific TP reductions (Table 4-1). Volume control: capture and retain 1.1 inches of runoff from new and fully reconstructed impervious (new/redevelopment); linear projects retain the larger of 0.55 inches from new/reconstructed impervious or 1.1 inches from net impervious increase; drawdown ≤48 hours.", "peak_flow_calculation_method": [ "NRCS/SCS curve number runoff methodology", "XP-SWMM runoff methodology", "NRCS MN MSE 3 storm distribution" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "XP-SWMM", "P8", "WinSLAMM" ], "approved_bmp_categories": [ "Pond systems/detention basins", "Infiltration cells (rain gardens)", "Infiltration trenches", "Filtration systems", "Vegetated channels", "Grit chambers", "Oil/water separators", "Green infrastructure" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Minneapolis Stormwater and Sanitary Sewer Guide", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Developed by Minneapolis Public Works Surface Water and Sewers Division", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "a duly licensed professional engineer under the laws of the state of Minnesota", "page_or_section": "Certification / Plan worksheets" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater and Sanitary Sewer Guide", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "October 2017 Revision #1: October 2021 Revision #2: February 2025", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Prepared by City of Minneapolis October 2017", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The City of Minneapolis considers the Minnesota Stormwater Manual, prepared by the MPCA, to be the City's approved design manual", "page_or_section": "Section 4.3.1.8, Page 34" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Rate control: No increase in the peak discharge over existing conditions for the 2-year, 10-year, and 100-year 24-hour storm event", "page_or_section": "Section 4.3.1.1, Page 20" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 4-3 City of Minneapolis design storm events—rainfall frequency depth Return Period Depth 2 years 2.8 inches 10 years 4.2 inches 100 years 7.5 inches", "page_or_section": "Table 4-3, Page 31" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water quality: Seventy percent (70%) removal of total suspended solids (TSS) from a 1.25-inch storm event. Sites discharging to a lake, pond, or wetland listed in Table 4-1 must ALSO reduce total phosphorus (TP) load as specified in the table", "page_or_section": "Section 4.3.1.2, Page 21" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Capture and retain 1.1 inches of runoff from the new and fully reconstructed impervious surfaces within the disturbed area for sites without restrictions", "page_or_section": "Section 4.3.1.3, Page 21" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Capture and retain larger of 0.55 inches of runoff from the new and fully reconstructed impervious surfaces; or 1.1 inches of runoff from the net increase in impervious surfaces", "page_or_section": "Section 4.3.1.3 B, Page 21" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The draw down time for the required volume control amount shall be 48-hours or less", "page_or_section": "Section 4.3.1.6, Page 27" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The storm distribution for the above-identified storm events shall be the NRCS MN MSE 3", "page_or_section": "Section 4.3.1.1, Page 20" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The methods preferred by the City include: NRCS/SCS curve number runoff methodology; XP-SWMM runoff methodology", "page_or_section": "Section 4.3.1.6, Page 26" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The hydrologic and hydraulic models accepted by the City of Minneapolis include: HydroCAD; XP-SWMM", "page_or_section": "Section 4.3.1.6, Page 26" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The water quality models accepted by the City of Minneapolis include: P8 (version 2.4 or newer); WinSLAMM (version 9.4.0 or newer)", "page_or_section": "Section 4.3.1.6, Page 26–27" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "A partial list of structural BMPs and devices includes pond systems/detention basins, infiltration cells (“rain gardens”), infiltration trenches, filtration systems, vegetated channels, grit chambers, and oil/water separators. BMPs that use the properties of vegetation or soil... are often referred to as “green infrastructure.”", "page_or_section": "Glossary, Stormwater best management practices" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water quality: Seventy percent (70%) removal of total suspended solids (TSS) from a 1.25-inch storm event.", "page_or_section": "4.3.1.3 Volume control, page 33" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "With less than three (3) feet of separation distance from the bottom of the infiltration system to the elevation of the seasonally saturated soils or the top of bedrock.", "page_or_section": "4.3.1.3 C Restrictions, page 34" }, { "field": "practice_mentions.bioretention", "excerpt": "infiltration cells (\"rain gardens\")... bio-retention areas", "page_or_section": "Glossary / Section 8.2.1, pages 11, 94" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "infiltration trenches", "page_or_section": "Glossary; Section 8.2.1, pages 11, 94" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous pavement (pervious concrete, porous asphalt, or porous pavers)", "page_or_section": "Section 8.2.1, page 94" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales... dry or wet swales", "page_or_section": "Glossary; Section 8.2.1, pages 11, 94" }, { "field": "practice_mentions.sand_filter", "excerpt": "Sand filters", "page_or_section": "Section 8.2.1, page 94" }, { "field": "practice_mentions.wet_pond", "excerpt": "pond systems/detention basins... Water quality ponds and wetlands", "page_or_section": "Glossary; Section 8.2.1, pages 11, 94" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention Basins... pond systems/detention basins", "page_or_section": "Appendix inspection examples; glossary, pages 11, 97" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Proprietary Device... oil/water separators... hydrodynamic separators", "page_or_section": "Glossary; Appendix B form; pre-treatment, pages 11, 101" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Municipal guide adopts MPCA Minnesota Stormwater Manual as the approved BMP design manual while stating city-specific rate, volume, and water-quality standards. Design storm depths in Table 4-3 are NOAA Atlas 14 values for HydroCAD/XP-SWMM. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www2.minneapolismn.gov/media/content-assets/www2-documents/government/Stormwater-and-Sanitary-Sewer-Guide.pdf", "landing_page_url": "https://www2.minneapolismn.gov/", "retrieved_at": "2026-08-08T10:35:20.744Z", "original_filename": "minneapolis-mn.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:12:26.786Z", "enrich_model": "composer-2.5:run-28e57762-3bcd-44b3-9ea1-c2ac77c66db4", "enrich_notes": "City ordinance standards in excerpts: 70% TSS from a 1.25-inch storm; volume retention 1.1 inches (new/redev) or larger of 0.55/1.1 inches (linear). Infiltration restricted where native rate exceeds 8.3 in/hr unless amended below 8.3 in/hr; minimum 3 ft separation to seasonally saturated soils/bedrock. BMP sizing/design details refer to MPCA Minnesota Stormwater Manual; Table 4-8 design infiltration rates not included in corpus. Rain garden O&M triggers action if standing water remains 72 hours after a storm (maintenance, not a stated design drawdown standard in excerpts).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "missoula-mt", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/missoula-mt/", "data_url": "https://stormwateratlas.com/data/manuals/missoula-mt.json", "document_metadata": { "jurisdiction_name": "City of Missoula", "jurisdiction_level": "municipality", "state_code": "MT", "document_title": "Montana Circular DEQ-8 — Subdivision Storm Water Drainage Standards", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024", "last_revised_date": "2024", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Initial Storm Water Facility must infiltrate, evapotranspire, and/or capture for reuse post-development runoff from the first 0.5 inches of rainfall on impervious areas (V = 0.5 × Aimp / 12).", "peak_flow_calculation_method": [ "Rational Method", "TR-55 / SCS Curve Number Method", "Storage-Indication Routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Initial Storm Water Facility", "Retention / Detention / Infiltration", "Bioretention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Missoula MS4 follows Montana DEQ-8 standards", "page_or_section": "Coverage note" }, { "field": "max_drawdown_hours", "excerpt": "Retention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "5.1 GENERAL, page 29" }, { "field": "max_drawdown_hours", "excerpt": "Detention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "6.1 GENERAL, page 31" }, { "field": "max_drawdown_hours", "excerpt": "Infiltration facilities must: ... D. Be sized to drain within 48 hours;", "page_or_section": "7.2 DESIGNS, page 34" }, { "field": "shwt_separation_inches", "excerpt": "For detention facilities that have a minimum one-foot separation from the bottom of the facility to the seasonally high groundwater or bedrock layer", "page_or_section": "6.2 DESIGN, page 31" }, { "field": "shwt_separation_inches", "excerpt": "Be constructed two feet above a limiting layer;", "page_or_section": "7.2 DESIGNS (infiltration), page 34" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "The measured infiltration must be divided by a safety factor of 2.0 to arrive at the design infiltration rate.", "page_or_section": "Appendix A, page 39-40" }, { "field": "practice_mentions.bioretention", "excerpt": "The BMPs may include infiltration basins, bioretention, biofiltration swales, extended detention basins, wet detention basins, and proprietary treatment devices.", "page_or_section": "Section 3 (standard plans BMPs), page 16" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Permeable pavement systems and dispersion BMPs are not allowed as the initial storm water facility.", "page_or_section": "Section 3, page 16" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Montana DEQ-8 (Helena pattern).", "fields_not_found": [] }, "source": { "document_url": "https://deq.mt.gov/files/Water/Forms/DEQ_8_2024_FINAL_2024_09_20.pdf", "landing_page_url": "https://deq.mt.gov/water", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "missoula-mt.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:13:14.517Z", "enrich_model": "composer-2.5:run-6850f362-3e07-4cea-b7d1-b5d020bb3243", "enrich_notes": "Montana DEQ-8 (Sanitation Act subdivisions): Initial Storm Water Facility volume is referenced via Chapter 3/Section 3.4 but the 0.5-inch WQv depth is not in these excerpts. Standard-plan BMPs may follow Montana Post-Construction Storm Water BMP Design Manual (Sept 2017) for 80% TSS; permeable pavement and dispersion BMPs are not allowed as the initial facility. Infiltration requires 24 in (2 ft) above a limiting layer at the infiltrative surface—broader than the 12 in SHWT/bedrock separation for detention; retention requires pond bottom 12 in above any limiting layer. Infiltration facilities must drain within 48 hours; retention and detention should not hold runoff more than 72 hours. Design infiltration rate is measured rate ÷ 2.0 safety factor per Appendix A; Table 3 rates are not included in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mobile-al", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/mobile-al/", "data_url": "https://stormwateratlas.com/data/manuals/mobile-al.json", "document_metadata": { "jurisdiction_name": "City of Mobile", "jurisdiction_level": "municipality", "state_code": "AL", "document_title": "Storm Water Manual Volume 1: Low Impact Development Design", "version_or_edition": "October 2023", "adoption_or_effective_date": "2023-10-01", "last_revised_date": "2023-10-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Optional LID water-quality practices (LID-WQPs) guidance for Mobile land development — nonstructural and structural LID practices to manage runoff volume and water quality (infiltration, vegetation, soils). Complements ADEM/Blue Book construction BMPs; Volume 2 BMP Design forthcoming.", "peak_flow_calculation_method": [ "LID site planning and design process", "Nonstructural and structural LID-WQPs" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Nonstructural LID water-quality practices", "Structural LID water-quality practices", "Bioretention / vegetation-soil based practices", "Infiltration-oriented LID" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Mobile", "page_or_section": "Cover / Map for Mobile" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Mobile", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Volume 1: Low Impact Development Design", "page_or_section": "TOC" }, { "field": "document_metadata.version_or_edition", "excerpt": "Literature Review. EPA-841-B-00-005, October 2000. The remainder of this page is intentionally left blank.", "page_or_section": "p. 28" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Literature Review. EPA-841-B-00-005, October 2000. The remainder of this page is intentionally left blank.", "page_or_section": "p. 28" }, { "field": "document_metadata.last_revised_date", "excerpt": "Literature Review. EPA-841-B-00-005, October 2000. The remainder of this page is intentionally left blank.", "page_or_section": "p. 28" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City of Mobile’s Storm Water Manual Volume 1 LID Design", "page_or_section": "About" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "What Are Water Quality Practices?; Advantages and Benefits of Stormwater LID-WQPs", "page_or_section": "Ch. 1–2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Land Development Planning and Design Process", "page_or_section": "Ch. 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "and design professionals. Chapter 4. Nonstructural LID‐WQPs (Guidance) − Chapter 4 explains the main categories of nonstructural LID‐WQPs and presents those that can be applied on land developments in the City. Chapter 5. Reserved Chapter 6. Structural LID‐WQP Design (Regulato", "page_or_section": "p. 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water quality storm is, in the City of Mobile, Alabama, 1.2 inches over a 24‐hour period preceded by a 72‐hour antecedent dry period.", "page_or_section": "Appendix A, Page A-3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = rainfall for the water quality storm (P = 1.2 inches)", "page_or_section": "6.5 Bioretention, Page 6.5-13" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the design must ensure that the WQV is still discharged from the bioretention area within 48 hours", "page_or_section": "6.5 Bioretention, Page 6.5-7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Should completely drain within 48 hours after a rainfall event", "page_or_section": "6.9 Infiltration Basin, Page 6.9-1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Permeable pavement systems should be designed to completely drain within 48 hours", "page_or_section": "6.10 Permeable Pavement, Page 6.10-1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The soil shall have an infiltration rate between 0.5 in/hr and 11 in/hr to support full drawdown within 48 hours after a storm event", "page_or_section": "6.8 Dry Bioswale, Page 6.8-7" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The total thickness of the reservoir layer ... shall not be less than nine (9) inches.", "page_or_section": "6.10 Permeable Pavement, Page 6.10-10" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Slope must not exceed 4% (1% to 2% is recommended).", "page_or_section": "6.7 Wet Bioswale, Page 6.7-10" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention areas are LID‐WQPs that capture and infiltrate (or temporarily store) the water quality volume (WQV)", "page_or_section": "6.5 Bioretention, Page 6.5-2" }, { "field": "practice_mentions.swale", "excerpt": "Maximum ponding in the wet bioswale is 18 inches.", "page_or_section": "6.7 Wet Bioswale, Page 6.7-10" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Engineered wetlands cannot be used for extended detention", "page_or_section": "6.11 Engineered Wetland, Page 6.11-3" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "LID‐MTDs ... Varies by MTD", "page_or_section": "Table 6.4, Page 6-5" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "LID Volume 1 is optional guidance; full BMP design volume not yet published. Medium confidence for MS4 design criteria coverage. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://mapformobile.org/wp/wp-content/uploads/2023/10/City-of-Mobile-LID-Design-Manual.pdf", "landing_page_url": "https://mapformobile.org/swm/", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "mobile-al.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:15:15.856Z", "enrich_model": "composer-2.5:run-e134c999-ffc7-4b62-875d-fa2f022ed112", "enrich_notes": "City defines water quality storm as 1.2 in over 24 h (72 h antecedent dry). WQV sizing uses 1.2Rv with Rv = 0.05 + 0.009(I). Native uncompacted soil without underdrain requires infiltration between 0.5 and 11 in/hr. SHWT separation varies by practice in text: 6 ft bottom-to-SHWT for bioretention, urban bioretention, and infiltration basin; 2 ft for dry bioswale and permeable pavement; wet bioswale feasibility table lists no minimum. Engineered wetlands cannot be used for extended detention; pocket/shallow wetland pool elevation tied within 6 in of SHWT. Permeable pavement reservoir minimum 9 in; underdrain outlets sized for 36–48 h reservoir drawdown. Wet bioswale max ponding 18 in (practice-specific, not mapped to bioretention_ponding field).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "montgomery-al", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/montgomery-al/", "data_url": "https://stormwateratlas.com/data/manuals/montgomery-al.json", "document_metadata": { "jurisdiction_name": "City of Montgomery", "jurisdiction_level": "municipality", "state_code": "AL", "document_title": "Low Impact Development Handbook for the State of Alabama (capital adopts ADEM LID guidance)", "version_or_edition": "ADEM LID Handbook", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Bioretention and other SCMs sized for the water quality / first-flush volume per ADEM LID Handbook design guidance. Practices include bioretention cells, constructed stormwater wetlands, swales, and related LID SCMs.", "peak_flow_calculation_method": [ "ADEM LID Handbook hydrology appendix", "SCM-specific design procedures" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention (BRC)", "Constructed stormwater wetlands (CSW)", "Swales", "Other LID SCMs per handbook" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Montgomery capital coverage via ADEM LID Handbook", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "municipality — City of Montgomery", "page_or_section": "Coverage note" }, { "field": "document_metadata.document_title", "excerpt": "Low Impact Development Handbook", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Conservation Committee. 2009. Alabama Handbook for Erosion Control, Sediment Control, and Stormwater Management on Construction Sites and Urban Areas. Montgomery, AL. Brown, R.A., W.F. Hunt, and S.G. Kennedy. 2009. Designing Bioretention with an Internal Water Storage (IWS) Lay", "page_or_section": "p. 9" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Environmental Services Branch for guidance at 334- 271-7700 or 1-800-533-2336. Trash Removal As needed In high traffiff c areas, frequent trash removal will befi necessary. Mulch removal from outlets As needed Mulch may collect in the outlet or overflrr ow during heavyfl ra", "page_or_section": "p. 9" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "bioretention is normally designed for the water quality or first flush", "page_or_section": "Bioretention chapter" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Appendix A: Stormwater Hydrology", "page_or_section": "TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention; Constructed Stormwater Wetlands", "page_or_section": "TOC" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Bioretention is normally designed for the water quality or \"first flush\" event, typically the first 1\"-1.5\" of rainfall", "page_or_section": "Chapter 4.1 Bioretention, page 7" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A BRC is designed to hold approximately the first inch of runoff (first flush) from the entire drainage area.", "page_or_section": "Chapter 4.1 Bioretention Design Guidance, page 36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A properly designed BRC will drawdown in <96 hours.", "page_or_section": "Chapter 4.1 Bioretention, page 8" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "BRCs should completely drain within 48 - 96 hours for the design rainfall volume captured.", "page_or_section": "Chapter 4.1 Bioretention, page 38" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table is at least 2' from the bottom of the cell", "page_or_section": "Chapter 4.1 Bioretention, page 32" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonally high water table should be a minimum of 2' below the permeable pavement base", "page_or_section": "Chapter 4.3 Permeable Pavement, page 80" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Media depths above the underdrain layer must be at least 3' to use IWS", "page_or_section": "Chapter 4.1 Bioretention, page 35" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention Media 36 or pollutant dependent", "page_or_section": "Table 4.1.5, page 40" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding depths should be no more than 12\" for safety reasons.", "page_or_section": "Chapter 4.1 Bioretention Design Guidance, page 36" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The subbase layer ... typically ranges from 2 – 4' deep, but can be a minimum of 9\".", "page_or_section": "Chapter 4.3 Permeable Pavement (PC Components), page 82" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "still retains stormwater within the wetland for a minimum of 48 hours", "page_or_section": "Chapter 4.2 Constructed Stormwater Wetlands, page 57" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The longitudinal slope should not exceed 5% where possible.", "page_or_section": "Chapter 4.4 Swales, page 94" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "18 - 36\" Max allowable height (h)", "page_or_section": "Chapter 4.2 CSW Cross Section, page 57" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable Birmingham city design-manual PDF; coverage via ADEM LID Handbook. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://adem.alabama.gov/programs/water/waterforms/LIDHandbook.pdf", "landing_page_url": "https://adem.alabama.gov/programs/water/nps/lid.cnt", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "montgomery-al.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 96, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 36, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 9, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": 48, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:15:59.342Z", "enrich_model": "composer-2.5:run-7ec5d4ee-f70e-4173-9574-afeb5f231e40", "enrich_notes": "Montgomery coverage follows ADEM LID Handbook. WQ treatment references first-flush rainfall (~1–1.5 in) and BRC sizing for ~first inch of runoff. BRC drawdown criteria span 48 h (surface) to 96 h (full cell). CSW temporary-pool drawdown target is 2–5 days (not mapped to ed_drain_time_hours). PP subbase/reservoir minimum depth 9 in; PA subbase often 18–36 in.", "enrich_schema_version": 2, "fields_not_found": [ "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "montpelier-vt", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/montpelier-vt/", "data_url": "https://stormwateratlas.com/data/manuals/montpelier-vt.json", "document_metadata": { "jurisdiction_name": "City of Montpelier", "jurisdiction_level": "municipality", "state_code": "VT", "document_title": "Vermont Stormwater Management Manual Volume I (capital MS4)", "version_or_edition": "DRAFT March 1, 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-03-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 10, 100 ], "water_quality_volume_method": "WQv = (P)(Rv)(A) / 12, where P = 1.0 inch, Rv = 0.05 + 0.009(I), I = percent impervious, A = site area in acres.", "peak_flow_calculation_method": [ "NRCS Runoff methods", "Watershed Lag Method", "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-55", "TR-20", "HECRAS" ], "approved_bmp_categories": [ "Pre-Treatment Practices", "Non-Structural Practices", "Structural Stormwater Treatment Practices", "Alternative Stormwater Treatment Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Montpelier capital MS4 follows Vermont Stormwater Management Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv = (P)(Rv)(A) / 12, where P = 1.0 inch", "page_or_section": "VSMM Vol I" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.0 inch across Vermont", "page_or_section": "Section 2.2.4 WQTS, page 16" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "equivalent to the first inch of rainfall", "page_or_section": "Section 2.2.4 WQTS, page 16" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time of 48 hours", "page_or_section": "Section 4.3.2 Dry Swales Design Summary, page 111" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time for Tv of 48 hours", "page_or_section": "Section 4.3.3 Infiltration Design Summary, page 124" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Vertical separation by at least three feet from the seasonally high groundwater table (SHGWT)", "page_or_section": "Section 4.3.3 Infiltration Design Summary, page 124" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum 3 foot separation to SHGWT from the bottom of the practice", "page_or_section": "Section 4.3.1 Bioretention Feasibility, page 101" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Filter Bed Depth 24-48 inches", "page_or_section": "Section 4.3.1 Bioretention Design Summary, page 97" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max. Ponding Depth 12 inches", "page_or_section": "Section 4.3.1 Bioretention Design Summary, page 97" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate of 0.2 in/hr or greater if exfiltrating", "page_or_section": "Section 4.3.1 Bioretention Design Summary, page 97" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "depth equal to or greater than four feet, but not more than eight feet", "page_or_section": "Section 4.3.6 Wet Pond Treatment, page 167" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours", "page_or_section": "Section 4.3.5 Treatment Wetland Design Summary, page 147" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "12 hours of extended detention is required and if a stormwater discharge is to a warm water fish habitat, 24 hours of extended detention is required", "page_or_section": "Section 2.2.5.2 Extended Detention Method, page 19" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall have a bottom width between two and eight feet", "page_or_section": "Section 4.3.2 Dry Swale Treatment, page 117" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Open channels constructed without check dams shall have a maximum longitudinal slope of 2%", "page_or_section": "Section 4.3.2 Dry Swale Feasibility, page 114" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Vermont Stormwater Management Manual draft/state standards.", "fields_not_found": [] }, "source": { "document_url": "http://legislature.vermont.gov/Documents/2016/WorkGroups/House%20Fish%20and%20Wildlife/Stormwater%20Manual%20Revisions/W~Kevin%20Burke~Draft%20Stormwater%20Manual%20Revisions%20DEC~3-22-2016.pdf", "landing_page_url": "https://dec.vermont.gov/watershed/stormwater", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "montpelier-vt.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.2, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:16:34.420Z", "enrich_model": "composer-2.5:run-25fd7c26-4253-4114-8b13-4fbe49237fa9", "enrich_notes": "WQv uses P=1.0 inch statewide; minimum 0.2 watershed inches on low-impervious sites. SHGWT separation varies by practice and CDA (1 ft/12 in, 2 ft/24 in, or 3 ft/36 in). Channel Protection extended detention release is 12 h (cold-water fisheries) or 24 h (warm-water). Length:width minima include wet pond 3:1, shallow wetland 2:1, gravel wetland 1:1. Bioretention filter drain time recommended max 48 h (2 days).", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "murfreesboro-tn", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/murfreesboro-tn/", "data_url": "https://stormwateratlas.com/data/manuals/murfreesboro-tn.json", "document_metadata": { "jurisdiction_name": "City of Murfreesboro", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Stormwater Planning & Low Impact Design Guide", "version_or_edition": "April 2008", "adoption_or_effective_date": "2008-04-01", "last_revised_date": "2008-04-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "WQv = 1.2 * Rv * A / 12 (acre-feet). Treat runoff from rainfalls up to 1.2 inches (85th percentile / Middle Tennessee). Streambank Protection Volume (SPv): controlled release of the 3.1-inch storm over 24 hours. Flood control: convey full build-out 100-year on-site without habitable structural flooding; downstream options per assessment.", "peak_flow_calculation_method": [ "Water Quality Protection Volume (WQv)", "Streambank Protection Volume (SPv) — 3.1-inch / 24-hr release", "Downstream hydrologic analysis for flood control" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Site design / LID practices (conserve natural features, reduce imperviousness)", "Structural stormwater controls (WQv / SPv / flood)", "Detention facilities with multi-step outlet controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Murfreesboro Plan Review Responsibilities", "page_or_section": "§1.1.4" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER PLANNING & LOW IMPACT DESIGN GUIDE", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv = 1.2 * Rv * A / 12 ... 1.2 inches of rainfall has been identified as the average depth corresponding to the 85th percentile storm for the Middle Tennessee region", "page_or_section": "§1.2.2.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the full build-out 100year storm event is to be conveyed on-site such that no resulting habitable structural flooding occurs", "page_or_section": "Table 1.2-1 Step 3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Provide on-site controlled release of the 3.1” storm event over a period of 24 hours (Streambank Protection Volume, SPV)", "page_or_section": "Table 1.2-1 Step 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city LID / planning guide", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "1.2 inches of rainfall has been identified as the average depth corresponding to the 85th percentile storm for the Middle Tennessee region.", "page_or_section": "1.2.2.1 Water Quality Protection Volume, page 18" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv = 1.2 * Rv * A / 12", "page_or_section": "1.2.2.1, page 18" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The water quality treatment requirement can be met by providing a 24-hour drawdown of a portion of WQv in a stormwater pond or wetland system", "page_or_section": "1.2.2.1, page 18" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "providing a 24-hour drawdown of a portion of WQv in a stormwater pond or wetland system (as described in Chapter 5). Referred to as water quality ED (extended detention)", "page_or_section": "1.2.2.1, page 18" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "The bottom width shall be a maximum of 6 feet.", "page_or_section": "1.2.2.2 Volume Reduction Method #3: Enhanced Swales, page 22" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The channel slope shall be 3 percent or less", "page_or_section": "1.2.2.2 Enhanced Swales, page 22" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Primary planning/LID guide (Apr 2008). Structural Controls Manual is published as separate CivicPlus DocumentCenter sections. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.murfreesborotn.gov/DocumentCenter/View/420/Stormwater-Planning-and-Low-Impact-Design-Guide", "landing_page_url": "https://www.murfreesborotn.gov/498/Stormwater-Quality-Design", "retrieved_at": "2026-08-10T09:39:14.757Z", "original_filename": "murfreesboro-tn.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 72, "swale_longitudinal_slope_percent": 3, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:18:46.241Z", "enrich_model": "composer-2.5:run-d80ce919-3f36-448c-8a50-591e55160106", "enrich_notes": "WQv rainfall depth 1.2 in (85th percentile, Middle Tennessee); formula WQv = 1.2 * Rv * A / 12. Water quality extended detention: 24-hour drawdown of portion of WQv in pond or wetland (Chapter 5). Enhanced swale volume-reduction criteria: bottom width maximum 6 ft, channel slope 3% or less, WQ storm velocity ≤1.0 ft/s, minimum residence time 5 min. Atlas: SPv = controlled release of 3.1-inch storm over 24 hours (not in provided chapter excerpts). Structural BMP detail referenced to Chapter 5 / separate Structural Controls Manual.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nashua-nh", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nashua-nh/", "data_url": "https://stormwateratlas.com/data/manuals/nashua-nh.json", "document_metadata": { "jurisdiction_name": "City of Nashua", "jurisdiction_level": "municipality", "state_code": "NH", "document_title": "New Hampshire Model Stormwater Standards / NH Stormwater Manual", "version_or_edition": "Draft: May, 2025", "adoption_or_effective_date": null, "last_revised_date": "2025-05", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 50, 100 ], "water_quality_volume_method": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall, Rv = 0.05 + 0.9(I), A = total site area draining to the structure.", "peak_flow_calculation_method": [ "TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "raingardens", "bioretention systems", "tree box filters", "subsurface gravel wetlands", "filtration practices", "infiltration practices", "swales", "detention areas" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "USDA/NRCS hydrologic soil group, as follows: Hydrologic Group Rd (inches) A 0.40 B 0.25 C 0.10 D 0.00 Channel Protection Volume (CPV) If the 2-year, 24-hour post-development storm volume does not increase due to development then: control the 2-year, 24-hour post-development p", "page_or_section": "pp. 10–11" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall", "page_or_section": "NH Model Stormwater Standards" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = (P)(Rv)(A) P = 1 inch of rainfall", "page_or_section": "Table 1, page 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "onsite retention of the first 1-inch of rainfall based on hydrologic soil group (HSG)", "page_or_section": "Element C.2.a, page 4" }, { "field": "practice_mentions.bioretention", "excerpt": "raingardens, bioretention systems, tree box filters", "page_or_section": "Element C.1.b, page 3" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "subsurface gravel wetlands", "page_or_section": "Element C.2.b, page 4" }, { "field": "practice_mentions.swale", "excerpt": "catch basins, swales, detention/bioretention areas", "page_or_section": "Element D.1.d, page 5" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NH Model Stormwater Standards (Manchester pattern).", "fields_not_found": [] }, "source": { "document_url": "https://extension.unh.edu/sites/default/files/media/2025-06/stormwater-management-standards.pdf", "landing_page_url": "https://extension.unh.edu/stormwater-center/nh-stormwater-manual", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "nashua-nh.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:19:08.359Z", "enrich_model": "composer-2.5:run-fec4f250-c6d2-4fed-9df1-31046b1245c2", "enrich_notes": "WQV uses P = 1 inch explicitly in Table 1; WPS cites onsite retention of the first 1-inch of rainfall by HSG. BMP sizing and pollutant removal (90% TSS, 60% TN/TP) defer to NH Stormwater Manual and UNH Stormwater Center; excerpts contain no SCM dimensional or drawdown criteria.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "new-haven-ct", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/new-haven-ct/", "data_url": "https://stormwateratlas.com/data/manuals/new-haven-ct.json", "document_metadata": { "jurisdiction_name": "City of New Haven", "jurisdiction_level": "municipality", "state_code": "CT", "document_title": "Connecticut Stormwater Quality Manual (city follows CT DEEP 2024 Manual)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-03-30", "last_revised_date": "2024-03-26", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV = (P)(R)(A)/12 where P = 1.3 inches (90th percentile rainfall event), R = volumetric runoff coefficient = 0.05 + 0.009(I).", "peak_flow_calculation_method": [ "NRCS Curve Number method", "Graphical Peak Discharge Method", "TR-20", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "WinTR-55", "HydroCAD", "TR-20" ], "approved_bmp_categories": [ "Pretreatment BMPs", "Infiltration BMPs", "Filtering BMPs", "Stormwater Pond BMPs", "Stormwater Wetland BMPs", "Water Quality Conveyance BMPs", "Stormwater Reuse BMPs", "Proprietary BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of New Haven follows CT Stormwater Quality Manual 2024", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — CT DEEP 2024 Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "𝑊𝑊𝑊𝑊𝑊𝑊 = (𝑃𝑃)(𝑅𝑅)(𝐴𝐴) 12 where: WQV = water quality volume (cubic feet) P = 1.3 inches (90th percentile rainfall event) R = volumetric runoff coefficient = 0.05+0.009( I) I = post- development impervious area (percent) after application of non-structural LID site p", "page_or_section": "p. 53" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.3 inches (90th percentile rainfall event)", "page_or_section": "Chapter 4, page 53" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention system should completely drain in 48 hours or less after the end of the design storm", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration system ... should be located at least 3 feet above the SHGT and bedrock", "page_or_section": "Chapter 10, page 194" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered bioretention soil media should have a depth of 24 to 48 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for water quality storm: 12 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "0.5 inches per hour (1.0 feet per day) for the bioretention soil media, whichever value is lower", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention basin should completely drain within 48 hours after the end of a storm.", "page_or_section": "Chapter 13 – Dry Extended Detention Basin, page 467" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width o Minimum: 2 feet", "page_or_section": "Chapter 13 – Wet Water Quality Swale, page 421" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green Roof Ground Slope Not Applicable (max 20% roof slope)", "page_or_section": "Chapter 8, Table 8-3, page 140" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via CT Stormwater Quality Manual 2024 (same pattern as other CT cities without local manuals).", "fields_not_found": [] }, "source": { "document_url": "https://portal.ct.gov/-/media/deep/water/water_quality_management/guidance/swm_mar_2024.pdf", "landing_page_url": "https://portal.ct.gov/DEEP/Water-Regulating-and-Discharges/Stormwater/Stormwater-Manual", "retrieved_at": "2026-08-10T09:45:18.924Z", "original_filename": "new-haven-ct.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 20, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:22:02.077Z", "enrich_model": "composer-2.5:run-0e815115-0391-4d18-a608-aa9720f5ccf6", "enrich_notes": "WQV uses P=1.3 in (90th percentile), not the prior 1-in storm. Infiltration suitability cites native soil rates ≥0.3 in/hr; unlined filtering systems require bottom ≥1 ft (12 in) above SHGT; infiltration bottom separation may be reduced to 2 ft (24 in) in limited cases. Bioretention with trees requires ≥30 in media depth. Wet swale max bottom width 8 ft (96 in). Water quality swales and permeable pavement noted for site slopes ~5% or less (selection context, not swale longitudinal design slope).", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "newark-nj", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/newark-nj/", "data_url": "https://stormwateratlas.com/data/manuals/newark-nj.json", "document_metadata": { "jurisdiction_name": "City of Newark", "jurisdiction_level": "municipality", "state_code": "NJ", "document_title": "New Jersey Stormwater BMP Manual / N.J.A.C. 7:8 (city MS4 follows NJDEP standards)", "version_or_edition": "Chapter 5: July 2023; Chapter 9.7: January 2026", "adoption_or_effective_date": "2023-07", "last_revised_date": "2026-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5). NRCS methodology computes WQDS runoff volume, peak rate, and hydrograph; BMPs such as small-scale bioretention must store/treat the entire WQDS volume.", "peak_flow_calculation_method": [ "USDA NRCS methodology (NRCS Runoff Equation and Dimensionless Unit Hydrograph)", "NRCS Curve Number (CN) method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Small-scale green infrastructure BMPs", "Small-scale bioretention systems", "Small-scale infiltration basins", "Green roofs", "Pervious paving systems", "Grass swales", "Cisterns", "Green Infrastructure MTDs / MTDs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Newark MS4 follows NJDEP Stormwater BMP Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — NJDEP BMP Manual / N.J.A.C. 7:8", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQDS: 1.25 inches of rain falling nonuniformly over 2 hours", "page_or_section": "N.J.A.C. 7:8-5.5 / Ch.5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The capacity of the underdrain must be sufficient to allow the system to drain within 72 hours", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7: Small-Scale Bioretention Systems (Page 74 / c0092)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the small-scale bioretention system with underdrain is installed in an area subject to pedestrian traffic, the drain time should be reduced to 24 hours", "page_or_section": "Chapter 9.7 Small-Scale Bioretention Systems (c0092)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The 72 hour maximum has not been exceeded, meaning the procedure may be continued", "page_or_section": "Chapter 5, Page 60 (c0054)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the minimum depth of 18 inches may not be sufficient", "page_or_section": "Chapter 9.7, Stormwater Tree Pit (c0097, Page 22)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "In sloped-bottom systems, the maximum longitudinal slope is 10%", "page_or_section": "Chapter 9.7, Bioretention Swale (c0097, Page 22)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table (SHWT) must be at least 1 foot below the bottom of the gravel layer", "page_or_section": "Chapter 9.7 (c0092, Page 74)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "which is greater than the 2 ft mimimum separation requirement", "page_or_section": "Chapter 9.7 Example 3, Step 4 (c0105, Page 34)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "For the WQDS, the maximum depth of runoff is 18 inches at the down-gradient end of a sloped-bottom system", "page_or_section": "Chapter 9.7, Bioretention Swale (c0097)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The depth of runoff above the surface of the soil bed is 12 in", "page_or_section": "Chapter 9.7 Example 1 (c0099, Page 23)" }, { "field": "design_parameters.practice_mentions.bioretention", "excerpt": "Small-scale bioretention systems are stormwater management", "page_or_section": "Chapter 9.7 (c0082, Page 64)" }, { "field": "design_parameters.practice_mentions.infiltration_basin", "excerpt": "proposed small-scale infiltration basin", "page_or_section": "Chapter 5 (c0050/c0054)" }, { "field": "design_parameters.practice_mentions.manufactured_treatment", "excerpt": "Note that an MTD is used for pretreatment so that exfiltration may be used", "page_or_section": "Chapter 9.7 (c0096, Page 19)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable Newark city design-manual PDF; municipality record via NJDEP BMP Manual (removed prior newark→NJDEP alias that caused state_only).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dep.nj.gov/wp-content/uploads/stormwater/bmp/njswbmp-chapter-9.7-small-scale-bioretention-systems-january-2026.pdf", "landing_page_url": "https://dep.nj.gov/stormwater/stormwater-management/bmp-manual/", "retrieved_at": "2026-08-10T09:45:18.903Z", "original_filename": "newark-nj.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 10, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "swale" ], "enriched_at": "2026-08-13T09:23:20.983Z", "enrich_model": "composer-2.5:run-fe96be95-fc85-4a40-989c-4faa4b791000", "enrich_notes": "WQDS rainfall depth (1.25 in per N.J.A.C. 7:8-5.5) is not stated in these excerpts. SHWT separation is explicitly 1 ft below gravel (underdrain bioretention) and 2 ft minimum between basin/soil bed bottom and SHWT (infiltration example)—not collapsed to one value. Ponding/runoff depth above soil bed is capped at 12 in (planter/underdrain example) and 18 in max at down-gradient for sloped-bottom bioretention swale under WQDS. Design exfiltration commonly uses half of tested saturated hydraulic conductivity (site-specific). Pedestrian areas: underdrain bioretention drain time reduced to 24 hr vs 72 hr general maximum.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "norfolk-va", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/norfolk-va/", "data_url": "https://stormwateratlas.com/data/manuals/norfolk-va.json", "document_metadata": { "jurisdiction_name": "City of Norfolk", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Norfolk Stormwater Design and Construction Manual", "version_or_edition": "Rev 3, July 1, 2024", "adoption_or_effective_date": "2024-07-01", "last_revised_date": "2024-07-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Virginia Runoff Reduction Method (VRRM) per Part II B / 9VAC25-875-590: new development total phosphorus load shall not exceed 0.41 pounds per acre per year. Redevelopment reducing P load at least 10% below predevelopment if disturbing greater than 2,500 square feet and less than one acre, or at least 20% if disturbing one acre or more. BMPs from the Virginia Stormwater BMP Clearinghouse; plan elevations include the water quality (1-inch) storm event plus 1-, 2-, and 10-year 24-hour storms (NOAA Atlas 14).", "peak_flow_calculation_method": [ "Rational Method (≤20 acres)", "Modified Rational Method (peak discharge only; ≤20 acres)", "SCS Graphical Peak Discharge Method (peak discharge only; >20 acres)", "SCS Tabular Method / runoff hydrograph (>20 acres)", "NRCS synthetic 24-hour rainfall distribution with TR-55 and TR-20", "U.S. Army Corps of Engineers hydrologic and hydraulic methods" ], "required_hydrologic_hydraulic_software": [ "Virginia Runoff Reduction Method (VRRM) Compliance Spreadsheet / worksheets" ], "approved_bmp_categories": [ "Manufactured Treatment Devices (Virginia DEQ BMP Clearinghouse MTDs)", "Underground storage/detention", "Extended Detention Pond", "Wet Pond", "Grass Channel", "Rooftop (Impervious Surface) Disconnection", "Sheet Flow to Vegetated Filter Strip/Conserved Open Space", "Vegetated Roof", "Rainwater Harvesting", "Dry Swales", "Wet Swales", "Constructed Wetlands", "Filtering Practices (non-cartridge)", "Soil Compost Amendment", "Permeable Pavement", "Infiltration Practices", "Bioretention (including Urban Bioretention)", "Virginia Stormwater BMP Clearinghouse BMPs (Coastal Plain design considerations required where listed)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Compliance with this document is required to ensure the general health, safety, and welfare of the citizens of the City of Norfolk (City)", "page_or_section": "Section 1.1 Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CITY OF NORFOLK, VA STORMWATER DESIGN AND CONSTRUCTION MANUAL", "page_or_section": "Header / Title" }, { "field": "document_metadata.state_code", "excerpt": "CITY OF NORFOLK, VA", "page_or_section": "Header" }, { "field": "document_metadata.document_title", "excerpt": "NORFOLK STORMWATER DESIGN AND CONSTRUCTION MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Rev 3, July 1, 2024", "page_or_section": "Page i / headers" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "The effective date of this design and construction manual is July 1, 2024.", "page_or_section": "Section 1.1 Purpose" }, { "field": "document_metadata.last_revised_date", "excerpt": "Rev 3, July 1, 2024", "page_or_section": "Page i" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "In addition to the requirements specified in the Virginia Stormwater Management Handbook and the Virginia Stormwater BMP Clearinghouse, the following requirements must be complied with when designing stormwater management systems for new development and redevelopment projects in the City of Norfolk", "page_or_section": "Section 5.3 City of Norfolk Design Criteria" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The prescribed design storms are the one-year, two-year, and 10-year 24-hour storms using the site-specific rainfall precipitation frequency data recommended by the U.S. National Oceanic and Atmospheric Administration (NOAA) Atlas 14.", "page_or_section": "Section 5.2.4 Design Storms and Hydraulic Methods" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 5.3: Design Storms... On-Site Storm Drain System... Minor Storm Drain System... Major Trunk Line... Regional Storm Water Facility... Pump Station... 10-year", "page_or_section": "Table 5.3, Page 5-37" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "A regional storm water facility shall allow a 100-year design storm to pass without flooding surrounding structures.", "page_or_section": "Table 5.3 definitions, Page 5-37" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The total phosphorus load of new development projects shall not exceed 0.41 pounds per acre per year, as calculated pursuant to 9VAC25-875-590. Please verify alignment with the latest approved Virginia Runoff Reduction Method (VRRM) criteria from DEQ.", "page_or_section": "Section 5.2.1 New Development" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For regulated land-disturbing activities defined as redevelopment that disturb greater than 2,500 square feet and less than one acre, the total phosphorus load shall be reduced at least 10% below the predevelopment total phosphorus load. For regulated land-disturbing activities defined as redevelopment that disturb greater than or equal to one acre, the total phosphorus load shall be reduced at least 20% below the predevelopment total phosphorus load.", "page_or_section": "Section 5.2.2 Redevelopment" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "the following elevations for each BMP shall be provided: (i) water quality (1-inch) storm event; (ii) 1-, 2-, and 10-year 24-hour storm events (NOAA Atlas 14)", "page_or_section": "Section 2.4.1 Stormwater Management Plan Contents" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Table 5.1: Runoff Calculation Methods... Rational Method... Modified Rational Method (peak discharge only) ≤ 20 Acres... SCS Graphical Peak Discharge Method... SCS Tabular Method (runoff hydrograph) > 20 Acres", "page_or_section": "Table 5.1, Page 5-37" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The U.S. Department of Agriculture's Natural Resources Conservation Service (NRCS) synthetic 24-hour rainfall distribution and models, including, but not limited to TR-55 and TR-20; hydrologic and hydraulic methods developed by the U.S. Army Corps of Engineers; or other standard hydrologic and hydraulic methods, shall be used to conduct hydraulic analysis for projects subject to Part II B of the Regulations.", "page_or_section": "Section 5.2.4" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "1D - Virginia Runoff Reduction Method (VRRM) Worksheets All VRRM calculations shall be performed using the 2011 Virginia bmp Clearinghouse Standards. The most current version of the worksheets may be found at Guidance & VRRM | Virginia DEQ", "page_or_section": "Plan checklist / VRRM worksheets" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Best Management Practices that are preferred on City property: 1. Manufactured Treatment Devices... 2. Underground storage/detention 3. Extended Detention Pond 4. Wet Pond 5. Grass Channel 6. Rooftop (Impervious Surface) Disconnection 7. Sheet Flow to Vegetated Filter Strip/Conserved Open Space 8. Vegetated Roof 9. Rainwater Harvesting 10. Dry Swales 11. Wet Swales 12. Constructed Wetlands 13. Filtering Practices", "page_or_section": "Section 5.1, Pages 5-31–5-32" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Best Management Practices that will be accepted on a case-by-case basis on City property: 1. Soil Compost Amendment 2. Permeable Pavement 3. Infiltration Practices 4. Bioretention (including Urban Bioretention)", "page_or_section": "Section 5.1, Page 5-32" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The BMPs listed on the Virginia Stormwater BMP Clearinghouse on the DEQ website are approved for use as necessary to effectively reduce the phosphorus load and runoff volume in accordance with the Virginia Runoff Reduction Method. Where a BMP listed on the Virginia BMP Clearinghouse contains Coastal Plain design considerations, these considerations shall be employed", "page_or_section": "Section 5.2.5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the following elevations for each BMP shall be provided: (i) water quality (1-inch) storm event; (ii) 1-, 2-, and 10-year 24-hour storm events (NOAA Atlas 14)", "page_or_section": "Section 2.4.1 / PAGE 2-23" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Manufactured Treatment Devices ... Please refer to the DEQ BMP Clearinghouse website for the most up to date list of approved MTD's.", "page_or_section": "Section 5.1 / PAGE 5-30" }, { "field": "practice_mentions.extended_detention", "excerpt": "3. Extended Detention Pond ... 15. Dry Extended Detention Ponds – No modification", "page_or_section": "Section 5.1; Appendix 4A" }, { "field": "practice_mentions.wet_pond", "excerpt": "4. Wet Pond ... 14. Wet Ponds – Table 14.2", "page_or_section": "Section 5.1; Appendix 4A" }, { "field": "practice_mentions.swale", "excerpt": "10. Dry Swales ... 11. Wet Swales ... A shallow swale may be necessary", "page_or_section": "Section 5.1; Section 2.3.1.2" }, { "field": "practice_mentions.green_roof", "excerpt": "8. Vegetated Roof ... 5. Vegetated Roofs – No modification", "page_or_section": "Section 5.1; Appendix 4A" }, { "field": "practice_mentions.bioretention", "excerpt": "4. Bioretention (including Urban Bioretention) ... all bioretention and infiltration practices proposed in the City of Norfolk must incorporate an appropriately sized underdrain.", "page_or_section": "Section 5.1; Appendix 4A" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "7. Permeable Pavement – All practices proposed in the City of Norfolk shall incorporate an appropriately sized underdrain", "page_or_section": "Appendix 4A" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "3. Infiltration Practices ... Infiltration practices are generally discouraged in the City of Norfolk due to the presence of a high ground water table", "page_or_section": "Section 5.1" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "12. Constructed Wetlands ... 13. Constructed Wetlands – No modification", "page_or_section": "Section 5.1; Appendix 4A" }, { "field": "practice_mentions.sand_filter", "excerpt": "Enhance sand filter media with a layer of organic matter.", "page_or_section": "Appendix (Structural BMP / bacteria guidance)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Municipal VESMP design/construction manual (effective July 1, 2024, Rev 3) implementing Virginia Part II B with Norfolk-specific drainage criteria. Design storms include Part II B 1/2/10-year 24-hour events, 10-year storm-drain design (Table 5.3), and 100-year regional facility pass. VRRM spreadsheet/worksheets are the only clearly mandated software; other H&H methods allowed by Table 5.1 / NRCS/USACE language. Infiltration generally discouraged due to high groundwater.", "fields_not_found": [] }, "source": { "document_url": "https://norfolk.gov/DocumentCenter/View/88177/Norfolk-Design-and-Construction-Manual_7-01-2024", "landing_page_url": "https://www.norfolk.gov/1499/Site-Plan-Review", "retrieved_at": "2026-08-08T10:27:34.427Z", "original_filename": "norfolk-va.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:26:29.363Z", "enrich_model": "composer-2.5:run-a51f560a-79e4-4819-b1fd-23b8a55104be", "enrich_notes": "Norfolk Rev 3 (July 1, 2024) implements Part II B / VRRM (0.41 lb P/ac/yr new dev); BMP detail is largely via Virginia Stormwater BMP Clearinghouse Handbook. City requires underdrains for permeable pavement, bioretention, infiltration, dry swales, and filtering practices; Level 2 subsoil testing for bioretention and dry swales; site-specific encased falling-head infiltration testing. Infiltration generally discouraged due to high groundwater. MTDs must be on DEQ Clearinghouse list at plan approval—not TAPE/NJCAT by name in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "north-little-rock-ar", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/north-little-rock-ar/", "data_url": "https://stormwateratlas.com/data/manuals/north-little-rock-ar.json", "document_metadata": { "jurisdiction_name": "City of North Little Rock", "jurisdiction_level": "municipality", "state_code": "AR", "document_title": "Stormwater Best Management Practices", "version_or_edition": "2025", "adoption_or_effective_date": "2025", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Construction-focused manual; no post-construction water quality volume formula. Temporary sediment traps/basins sized for settling and storage zones of at least 70 CY/acre and 53 CY/acre of contributing drainage area, respectively, based on ½ inch of runoff volume over a 24-hour period. Site BMPs must be inspected every seven calendar days and within 24 hours of a rainfall event of 0.5 inches or greater.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Mulch and Straw Cover", "Rolled Erosion Control Practices (RECP)", "Wetting / Dust Control", "Outlet Protection", "Inlet Protection", "Silt Fence", "Compost Socks", "Sediment Basins / Sediment Traps", "Construction Entrance/Exit", "Runoff Control – Ditches and Check Dams", "Concrete Washouts", "Spill Prevention", "Stockpile Management" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of North Little Rock ... A practical guide to protecting North Little Rock’s water ways", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "as mandated by the City’s Municipal Separate Storm Sewer System (MS4) permit", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Arkansas Department of Environmental Quality’s General Permit for Small MS4s", "page_or_section": "Section 1.2" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER BEST MANAGEMENT PRACTICES", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "City of North Little Rock2025", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "City of North Little Rock2025", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual is issued under the authority of the City of North Little Rock’s Stormwater Ordinance (Chapter 14 of municipal code) and supports the City’s responsibilities as a regulated Municipal Separate Storm Sewer System (MS4)", "page_or_section": "Section 1.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Size traps to accommodate both a settling and storage zone with minimum volumes of 70 CY/acre and 53 CY/acre of contributing drainage area, respectively, based on ½” of runoff volume over a 24-hour period.", "page_or_section": "Section 3.3.5 Sediment Basins" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Sites must be inspected every seven calendar days and within 24 hours of a rainfall event of .5 inches or greater.", "page_or_section": "Section 3.5 Inspection and Maintenance Guidelines" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "3.2 Erosion Control Practices ... 3.3 Sediment Control Practices ... 3.4 Good Housekeeping Measures ... Mulch & Straw Cover ... RECP ... Outlet Protection ... Inlet Protection ... Silt Fence ... Compost Socks ... Sediment Basins ... Construction Entrance ... Concrete Washouts", "page_or_section": "Table of Contents; Sections 3.2–3.4" }, { "field": "practice_mentions.swale", "excerpt": "Earth dikes, swales and lined ditches can be constructed at the top/bottom of slopes, to direct run-on and runoff around stockpiles", "page_or_section": "3.4.1 Runoff Control - Ditches and Dams, page 16" }, { "field": "enrich_notes.sediment_trap_sizing", "excerpt": "Size traps to accommodate both a settling and storage zone with minimum volumes of 70 CY/acre and 53 CY/acre of contributing drainage area, respectively, based on ½\" of runoff volume over a 24-hour period", "page_or_section": "3.3.5 Sediment Basins, page 14" }, { "field": "enrich_notes.inspection_rainfall", "excerpt": "Sites must be inspected every seven calendar days and within 24 hours of a rainfall event of .5 inches or greater", "page_or_section": "3.5 Inspection and Maintenance Guidelines, page 20" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Construction-phase BMP manual for North Little Rock MS4 (Chapter 14). Explicitly states this edition focuses primarily on construction-phase controls; post-construction design storms, peak-flow methods, and hydrologic software are not specified. Sediment trap sizing uses ½-inch runoff over 24 hours; 0.5-inch rainfall is an inspection trigger, not a return-period design storm.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://nlr.ar.gov/download/629/plans-and-specs/18083/nlr-stormwater-best-management-practices-v20251017.pdf", "landing_page_url": "https://nlr.ar.gov/", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "north-little-rock-ar.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T09:27:05.913Z", "enrich_model": "composer-2.5:run-d04332f8-7919-455a-9a5e-00d5228544f6", "enrich_notes": "Construction-phase BMP manual (Chapter 14 MS4); post-construction design storms and hydrologic sizing for SCMs are not specified. Sediment traps/basins use settling zone 70 CY/acre and storage zone 53 CY/acre based on ½ inch runoff over 24 hours (construction sizing, not a stated WQv). Site inspection every 7 calendar days and within 24 hours after rainfall ≥0.5 inches. Permit threshold 4,000 sf disturbance; commercial ≥5 acres.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "oakland-ca", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/oakland-ca/", "data_url": "https://stormwateratlas.com/data/manuals/oakland-ca.json", "document_metadata": { "jurisdiction_name": "City of Oakland", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Storm Drainage Design Standards", "version_or_edition": "2014", "adoption_or_effective_date": null, "last_revised_date": "2014", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "C.3 stormwater quality measures referenced; primary document is drainage/hydraulics standards. Peak reduction into City system limited (up to 25%).", "peak_flow_calculation_method": [ "Modified Rational Method for watersheds <320 acres", "Synthetic unit hydrograph for watersheds ≥320 acres", "Detention designed for 100-year; up to 25% peak reduction into City system" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention", "C.3 stormwater quality measures (referenced)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Oakland Storm Drainage Design Standards", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Oakland", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Storm Drainage Design Standards", "page_or_section": "Title" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "C.3 stormwater quality measures", "page_or_section": "References" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Modified Rational / Synthetic UH; 25% peak reduction", "page_or_section": "Hydrology / detention" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "................................ 5 3.6. Detention Facilities..................................................................................................... 5 4. TAILWATER ELEVATIONS IN FLOOD ZONES & DESIGN DISCHARGE FREQUENCIES ..............................................", "page_or_section": "p. 3" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The facility shall be designed such that the water surface returns to its original elevation within 48 hours, after the cessation of a 100-year, 24-hour rainstorm over the contributory watershed.", "page_or_section": "3.5 Retention Facilities, page 8" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention pond shall be designed such that the water surface returns to its base or starting elevation within 24 hours after the cessation of a 24-hour, 100-year storm.", "page_or_section": "3.6 Detention Facilities, page 9" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Be certain that the detention basin returns to the starting elevation within 24 hours of the end of the 100-year storm event.", "page_or_section": "3.6 Detention Facilities, page 10" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Minimum bottom width for open channels with established vegetated bottoms and sides shall be no less than four (4) feet.", "page_or_section": "3.2 Conveyance Facilities Minimum Requirements, page 7" }, { "field": "practice_mentions.bioretention", "excerpt": "builders and developers are encouraged to employ concepts of bio-retention, swales, pervious pavers, rain barrels, cisterns, tree wells", "page_or_section": "3.6.1 Design Procedure, page 9" }, { "field": "practice_mentions.swale", "excerpt": "Commonly utilized storm water quality control measures shown in the Alameda Countywide Clean Water Program (C.3 Requirements) such as pervious ground cover, grassy swales, tree wells, rain gardens, infiltration, retention", "page_or_section": "3.1 General Standards, page 6" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Oakland 2014 drainage standards; C.3 WQ largely by reference to MRP/regional guidance. Pipeline excerpt repair removed 5 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date", "document_metadata.relationship_to_state_manual", "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://cao-94612.s3.us-west-2.amazonaws.com/documents/City-of-Oakland-Design-Standards.pdf", "landing_page_url": "https://www.oaklandca.gov/Community/Community-Development/Sustainability-Environment/Creeks-Watershed-and-Stormwater/Storm-Drainage-Design-Standards", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "oakland-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 48, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:30:39.632Z", "enrich_model": "composer-2.5:run-b93f0716-6deb-4584-9b6d-de6115cd741b", "enrich_notes": "Oakland 2014 Storm Drainage Design Standards emphasize peak flow reduction up to 25% and detention; stormwater quality (WQv) sizing is by reference to Alameda Countywide Clean Water Program C.3 Technical Guidance, not numeric WQ depth in this manual. Retention basins (no surface outflow) must dewater to original elevation within 48 hours after a 100-year, 24-hour storm; detention ponds must return to base elevation within 24 hours after a 100-year, 24-hour storm. Parking-lot detention ponding depth cap is 4 inches (not mapped to bioretention ponding). Minimum vegetated open-channel bottom width is 4 ft (48 in); engineered swale velocities for C.3 are in external C.3 Guidance.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "olympia-wa", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/olympia-wa/", "data_url": "https://stormwateratlas.com/data/manuals/olympia-wa.json", "document_metadata": { "jurisdiction_name": "City of Olympia", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Management Manual for Western Washington (Ecology 2024; city MS4)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "Adopts Ecology Stormwater Management Manual for Western Washington (SWMMWW) Minimum Requirements including runoff treatment and flow control. Local drainage manuals/ordinances typically supplement SWMMWW for city conditions; continuous simulation (WWHM/HSPF) sizes flow control.", "peak_flow_calculation_method": [ "Continuous Simulation Models", "WWHM / HSPF", "Single Event Hydrograph Method", "SBUH / SCS / NRCS methods (as allowed)" ], "required_hydrologic_hydraulic_software": [ "WWHM", "HSPF" ], "approved_bmp_categories": [ "Flow Control BMPs", "Runoff Treatment BMPs", "LID BMPs", "Source Control BMPs", "Infiltration / bioretention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Olympia MS4 follows Ecology SWMMWW", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — Ecology SWMMWW 2024", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Document that the maximum ponded depth from the infiltration BMP can infiltrate through the infiltration BMP surface within 48 hours.", "page_or_section": "Volume V - Chapter 5 - Page 823 (SSC-4 Drawdown Time)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "In most cases, UIC wells are designed to completely drain ponded runoff within 48 to 72 hours after flow to the UIC well has stopped.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The \"Default\" and \"Custom\" BSM depth must be 18 inches to provide Runoff Treatment and good growing conditions for selected plants.", "page_or_section": "Volume V - Chapter 5 - Page 921 (Soil Depth)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The minimum vertical separation is 5 feet between the base of a UIC well and the highest elevation between the seasonal high groundwater table, bedrock, hardpan, or other low-permeability layer.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of BMP T7.10: Infiltration Ponds or BMP T7.20: Infiltration Trenches shall be ≥ 5 feet above the seasonal high-water mark, bedrock (or hardpan) or other low permeability layer. A separation down to 3 feet may be considered", "page_or_section": "Volume V - Chapter 5 - Page 823 (SSC-5)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "If the high water table extends to within five (5) feet of the bottom of an infiltration BMP, the site is seldom suitable.", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Where the minimum vertical separation of 1 foot to the seasonal high water table, bedrock, or other impervious layer would not be achieved below bioretention that would serve a drainage area that is less than:", "page_or_section": "Volume V - Chapter 5 - Page 896" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "greater than 3 feet below the bottom of BMP T7.30: Bioretention, or greater than 1 foot below the bottom of the lowest gravel base course of BMP T5.15: Permeable Pavement", "page_or_section": "Volume III - Chapter 3 - Page 514" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "They are not generally appropriate for sites that have a design infiltration rate less than 0.3 inches per hour.", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Design (long-term) infiltration rates up to 3 in/hr can also be considered", "page_or_section": "Volume V - Chapter 5 - Page 822 (SSC-4)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Use an initial saturated hydraulic conductivity (Ksat) for the Bioretention Soil Mix (BSM) of 12 in/hr.", "page_or_section": "Volume V - Chapter 5 - Page 910" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Deep ponds (greater than 8 feet) may stratify during summer", "page_or_section": "Volume III - Chapter 1 - Page 478 (Maximum Depth)" }, { "field": "practice_mentions.swale", "excerpt": "biofiltration swales are usually situated on sites with slopes of less than 6%", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Minimum slope = 1% to 2% to allow for surface overflow in extreme rainfall", "page_or_section": "Volume V - Chapter 5 - Page 838 (Slope Considerations)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "The permeable pavement design includes a 6\" layer of sand that meets the size gradation (by weight) given in Table V-7.1: Sand Medium Specification.", "page_or_section": "Volume V - Chapter 5 - Page 838" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "biological treatment method, such as a biofiltration swale or constructed wetland.", "page_or_section": "Volume I - Chapter 4 - Page 171" }, { "field": "practice_mentions.bioretention", "excerpt": "runoff from these types of landscaped areas should be directed to bioretention, biofiltration, or constructed wetland BMPs prior to discharge to UIC wells.", "page_or_section": "Volume I - Chapter 4 - Page 171" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Ecology SWMMWW (Vancouver/Bellevue western WA pattern). Prefer city drainage manual if a durable public PDF is later found.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.cityofcamas.us/sites/default/files/fileattachments/community_development/page/9505/2024swmmww_6-14-24.pdf", "landing_page_url": "https://www.olympiawa.gov/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "olympia-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:33:13.010Z", "enrich_model": "composer-2.5:run-3b19c566-99c2-43b8-b39f-93267a53792a", "enrich_notes": "Excerpts are Ecology SWMMWW (2024), adopted for Olympia MS4 context. Seasonal high groundwater separation varies by BMP and drainage area (e.g. 1 ft rain garden/small bioretention/permeable base, 3 ft larger bioretention, 5 ft infiltration ponds/trenches and UIC presumptive, 3 ft UIC/alternate infiltration with analysis). Infiltration drawdown check is 48 h; UIC wells cite 48–72 h pond drain. BSM default/custom treatment media depth is 18 in; BSM end-of-life design Ksat uses 12 in/hr (not a single native-soil design rate in these excerpts). Permeable pavement treatment sand layers are 6 in (basic) and 12 in (basic + metals); minimum surface slope 1–2%.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "omaha-ne", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/omaha-ne/", "data_url": "https://stormwateratlas.com/data/manuals/omaha-ne.json", "document_metadata": { "jurisdiction_name": "City of Omaha", "jurisdiction_level": "municipality", "state_code": "NE", "document_title": "Post-Construction Stormwater Management Planning (PCSMP) / ORSDM Ch.8 BMPs", "version_or_edition": "March 2009 (PCSMP guidance); ORSDM April 2006+", "adoption_or_effective_date": "2008-07-01", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Omaha Municipal Code Ch.32/53 PCSMP: low-impact development BMPs providing water quality control of the first one-half inch (0.5\") of runoff from the site (required for plats on/after July 1, 2008; maximize 0.5\" control where reasonably practical for older plats / ≥1-acre disturbance). ORSDM Chapter 8 provides BMP design criteria, pretreatment, and feasibility. Full ORSDM is chaptered and often 403-blocked on city servers.", "peak_flow_calculation_method": [ "ORSDM hydrology / detention criteria (Chapters 2+)", "PCSMP BMP sizing calculations" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Low impact development BMPs", "ORSDM Chapter 8 stormwater quality BMPs", "Bioretention / permeable pavement / other ORSDM practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Omaha - POST-CONSTRUCTION STORMWATER MANAGEMENT PLAN (PCSMP)", "page_or_section": "Header" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "provide water quality control of the first one-half inch of runoff from the site", "page_or_section": "Table 1 / §1.2 Applicability" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 8 of the Omaha Regional Stormwater Design Manual provides information about BMPs", "page_or_section": "§1.0 / resources" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "PCSMP that includes low impact development BMPs that provide water quality control of the first one‐half inch of runoff from the site", "page_or_section": "Table 1, page 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Calculating the volume of selected BMPs is simply based on the first one‐half inch (0.5\") of stormwater runoff.", "page_or_section": "Section 2.4 BMP Calculations, page 11" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In all cases where control of the first 0.5 inch of runoff cannot be achieved, the management plan should provide BMPs that maximize control", "page_or_section": "Section 2.0, page 7" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Extracted from PCWP PCSMP planning guide citing ORSDM Ch.8. Prefer full ORSDM chapters when durable public PDFs are available.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://papiopartnership.org/wp-content/uploads/2017/11/post_construction_stormwater_planning.pdf", "landing_page_url": "https://www.omahastormwater.org/resources/forms-downloads/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "omaha-ne.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:33:37.147Z", "enrich_model": "composer-2.5:run-72c5ef4a-6042-4e63-bd2d-aa1c0bb66a9a", "enrich_notes": "PCSMP (March 2009) is a submittal/planning guide; BMP sizing uses WQCV from drainage area × 0.5 in runoff (1815 cf/ac, 42 cf/1000 sf, 4.2 cf/100 sf). Detailed design criteria, pretreatment, and feasibility are referenced to ORSDM Chapter 8, not reproduced in these excerpts. Proprietary BMPs require pre-approval by City of Omaha Public Works; no TAPE/NJCAT-style program named. Combined-sewer areas (generally east of 72nd St.) require no net peak increase vs. Oct 2002 pre-development for 2-, 10-, and 100-year events in addition to WQCV.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "orlando-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/orlando-fl/", "data_url": "https://stormwateratlas.com/data/manuals/orlando-fl.json", "document_metadata": { "jurisdiction_name": "City of Orlando", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Engineering Standards Manual", "version_or_edition": "2026", "adoption_or_effective_date": null, "last_revised_date": "2026", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Chapter 7 Stormwater Management: pollution abatement & flow attenuation (7.04.01). City accepts SSRWMD/SFWMD ERP Applicant Handbook criteria and FDOT erosion manuals except as specifically addressed. Retention/detention facilities required components.", "peak_flow_calculation_method": [ "Hydraulic design criteria for roadway drainage, storm sewers, culverts, open channels (Section 7.05)", "Pollution abatement and flow attenuation facilities", "Primary/secondary/tertiary/roadway conveyance facilities" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention facilities", "Detention facilities", "Pollution abatement facilities", "Storm sewers and conveyance" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Orlando", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Orlando corporate limits", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "SFWMD Permit Information Manual", "page_or_section": "Accepted criteria" }, { "field": "document_metadata.document_title", "excerpt": "Engineering Standards Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "SSRWMD Permit Information Manual, and SFWMD Permit Information Manual", "page_or_section": "Accepted criteria" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "shall not increase the existing 100-year flood elevation", "page_or_section": "Chapter 7 / related standards" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Pollution Abatement & Flow Attenuation", "page_or_section": "Section 7.04.01" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Hydraulic Design Criteria", "page_or_section": "Section 7.05" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention/Detention Facilities", "page_or_section": "Chapter 7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "return pond to designed ponding elevation within 72 hours of rain events", "page_or_section": "Section 7.06 maintenance, page 99 (orlando-fl-c0140)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "pond to drawdown to designed elevation within 72 hours or prolonged wetness is evident", "page_or_section": "Section 7.06 Underdrain Maintenance, page 99" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum of two feet (2') between the bottom of the base to a standing surface water condition or seasonal high groundwater table", "page_or_section": "Section 7.05.01 A, page 89 (orlando-fl-c0130)" }, { "field": "practice_mentions.swale", "excerpt": "A grass swale is defined as a trench which: a. Has a top width-to-depth ratio of the cross-section equal to or greater than 12:1", "page_or_section": "Section 7.05.05 Open Channel Design, page 96" }, { "field": "practice_mentions.wet_pond", "excerpt": "Dry detention is not allowed. Wet detention shall be constructed in accordance with the requirements of SJRWMD", "page_or_section": "Section 7.04.01, page 85 (orlando-fl-c0126)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Orlando ESM 2026 Ch 7; detailed numeric WQ volumes may defer to SFWMD/SJRWMD handbooks. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.orlando.gov/files/sharedassets/public/v/3/documents/engineering/platting/2026_engineeringstandardsmanual.pdf", "landing_page_url": "https://www.orlando.gov/Our-Government/Records-and-Documents/Engineering-Documents", "retrieved_at": "2026-08-10T08:05:33.346Z", "original_filename": "orlando-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:35:29.548Z", "enrich_model": "composer-2.5:run-f6b99159-f939-44ba-b437-1455f6b3b506", "enrich_notes": "Chapter 7.04.01 defers pollution abatement and wet detention design to SJRWMD/SFWMD ERP criteria; Orlando prohibits dry detention and will not waive SJRWMD littoral zone in exchange for extra permanent pool volume. Numeric WQv depths and BMP sizing are not stated in these ESM excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "overland-park-ks", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/overland-park-ks/", "data_url": "https://stormwateratlas.com/data/manuals/overland-park-ks.json", "document_metadata": { "jurisdiction_name": "City of Overland Park", "jurisdiction_level": "municipality", "state_code": "KS", "document_title": "Design and Construction Standards — Volume 1 Design Criteria", "version_or_edition": "2023 (adopted November 1, 2023)", "adoption_or_effective_date": "2023-11-01", "last_revised_date": "2023-11-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Adopts KC-APWA Section 5600 Storm Drainage Systems and Facilities by reference with Overland Park amendments (detention 5608, conveyance, treatment facilities). Stormwater detention per OPMC 15.10 and Section 5608 as amended; stormwater treatment facility standards adopted by Public Works. MARC/APWA BMP Manual typically used regionally for water quality (confirm via city ES policies).", "peak_flow_calculation_method": [ "KC-APWA Section 5600 as amended by Overland Park", "Detention basin sizing / release rates (Section 5608 amendments)", "Stormwater management studies per ES Policy 3-01", "Stream corridor / conveyance rules (OPMC 15.10 / 18.365)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater conveyance facilities", "Detention / underground storage", "Stormwater treatment facilities", "Engineered / bio swales" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Overland Park / Planning and Development Services / Public Works", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Overland Park", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "DESIGN AND CONSTRUCTION STANDARDS", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "and Private Alleys 2 1. Standards Adopted by Reference 2 2. Street Classification 2 3. Right of Way Design Standards: Table I 3 4. Table 1A - Required Street Widths - Local Residential Streets 4 4. Geometric and Pavement Design Standards: Table II 5 5. Planned Residential Z", "page_or_section": "p. 2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Adoption of KC-APWA Section 5600 by Reference", "page_or_section": "Stormwater Conveyance Facilities" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater Treatment Facilities / Detention Basin Size", "page_or_section": "Section C / 5608.4.D" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Section 5600 - Storm Drainage Systems and Facilities ... adopted by reference", "page_or_section": "B.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Detention / Stormwater Treatment Facilities", "page_or_section": "5608 / Section C" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv = P x Rv where P = 1.37 inches and Rv = 0.05 + 0.09(I)", "page_or_section": "Page 67 / Appendix B.2.12 example (c0074)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Natural conveyance swales shall have an average minimum longitudinal slope of 2% measured from the beginning of the swale to the discharge point", "page_or_section": "Section II.B.2.c.v, Page 10 (c0030)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "City amendments to KC-APWA 5600; full numeric criteria in referenced APWA/MARC manuals. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://content.civicplus.com/api/assets/ks-overlandpark/2e50125c-ea9f-462d-8053-f153e5f23e1c?cache=1800", "landing_page_url": "https://www.opkansas.org/", "retrieved_at": "2026-08-10T08:48:28.515Z", "original_filename": "overland-park-ks.pdf" }, "design_parameters": { "wqv_depth_inches": 1.37, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:36:12.908Z", "enrich_model": "composer-2.5:run-d6b161ce-7c87-41a3-84e0-85f4bc90a7c7", "enrich_notes": "Volume I adopts KC-APWA Section 5600 (conveyance/detention) and the October 2012 MARC/APWA BMP Manual for stormwater treatment by reference; most numeric BMP criteria are not restated in city amendments. City text adds setbacks (e.g., 20 ft from WQv pool to residential structures for infiltration facilities), rain-garden drainage area limit of 1 acre, natural conveyance swale sizing (10% storm, 2% min slope, 6 ft/s max velocity), and detention release-rate policy. Appendix dog-kennel example cites BMP Manual WQv with P = 1.37 in and infiltration trench retention time 48–72 h in example equations only.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "palm-bay-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/palm-bay-fl/", "data_url": "https://stormwateratlas.com/data/manuals/palm-bay-fl.json", "document_metadata": { "jurisdiction_name": "City of Palm Bay", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Jacksonville Land Development Procedures Manual Volume 2 (SJRWMD-region municipal pattern)", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "SJRWMD ERP AH Vol II PDF not publicly fetchable (403). Using Jacksonville LDPM Vol 2 wet detention / SMF pattern as east-central Florida municipal reference: wet detention and stormwater management facilities per Table 3.7-1; MSMP 2070 rainfall depths for multi-return-period 24-hour storms. Prefer SJRWMD AH Vol II when a durable PDF is available.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage contexts", "Design rainfall depths from MSMP 2070" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Palm Bay (SJRWMD) — coverage via Jacksonville LDPM Vol 2 pattern", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 Grassed Conveyance Swales, Recovery" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 Shallow Bioretention, Recovery" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3, Recovery Requirements" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: To receive pollutant-load-reduction credits, the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3, Implementation Considerations" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 Shallow Bioretention, Implementation Considerations" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.2, Physical Constraints" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3, Design Criteria" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3, Sizing Requirements" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Canonical SJRWMD special_district record: fl-sjrwmd-erp-ah2. Placeholder pending durable SJRWMD AH Vol II or city design-manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.sjrwmd.com/documents/permitting/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "palm-bay-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:39:20.626Z", "enrich_model": "composer-2.5:run-2096d1bd-7e49-4b7f-bcee-fedc566d86eb", "enrich_notes": "Corpus is Jacksonville LDPM Vol 2 (SJRWMD municipal pattern) used as Palm Bay proxy. Swale WQ sizing references SJRWMD 3-year/1-hour storm percolation; wet detention example uses ERP Handbook residence-time equations and treatment volumes (1 in vs 2.5 in over impervious) in a worked example, not a single mandated WQv depth. Infiltration design uses field rate divided by 2 (swale) or safety factor 2 (detention basin borings)—site-specific, not one jurisdiction-wide design rate.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "palm-coast-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/palm-coast-fl/", "data_url": "https://stormwateratlas.com/data/manuals/palm-coast-fl.json", "document_metadata": { "jurisdiction_name": "City of Palm Coast", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Jacksonville Land Development Procedures Manual Volume 2 (SJRWMD-region municipal pattern)", "version_or_edition": "Effective January 2026", "adoption_or_effective_date": "2026-01-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "SJRWMD ERP AH Vol II PDF not publicly fetchable (403). Using Jacksonville LDPM Vol 2 wet detention / SMF pattern as east-central Florida municipal reference: wet detention and stormwater management facilities per Table 3.7-1; MSMP 2070 rainfall depths for multi-return-period 24-hour storms. Prefer SJRWMD AH Vol II when a durable PDF is available.", "peak_flow_calculation_method": [ "Rational Method and SCS methods as applicable", "Stormwater management facility storage contexts", "Design rainfall depths from MSMP 2070" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention", "Stormwater management facilities (SMFs)", "Other LDPM Vol 2 BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Palm Coast (SJRWMD) — coverage via Jacksonville LDPM Vol 2 pattern", "page_or_section": "Coverage note" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Standing water must be recovered within 72 hours.", "page_or_section": "Section 4.3 Grassed Conveyance Swales (Recovery)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All standing water must be recovered through surface discharge or percolation in less than 72 hours under SHWL conditions", "page_or_section": "Section 4.3 Recovery Requirements" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface ponding area must be recovered within 72 hours.", "page_or_section": "Section 4.4 Shallow Bioretention (Recovery)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: SHWL should be a minimum of 6 inches below the bottom of the planting media or nutrient- sorption layer.", "page_or_section": "Section 4.4 Shallow Bioretention" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "SHWL – Must be at least 0.5 foot below the bottom of the surface ponding area.", "page_or_section": "Section 4.4.2 Physical Constraints" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Shallow Water Table: To receive pollutant-load-reduction credits, the SHWL should be at least 6 inches below the bottom of the grassed conveyance swale.", "page_or_section": "Section 4.3 Grassed Conveyance Swales" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Recommended bottom width of 2 to 8 feet.", "page_or_section": "Section 4.3 Design Criteria" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "the swale should have an approximately trapezoidal shape with a bottom width of at least 2 feet to allow mowing.", "page_or_section": "Section 4.3 Sizing Requirements" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Canonical SJRWMD special_district record: fl-sjrwmd-erp-ah2. Placeholder pending durable SJRWMD AH Vol II or city design-manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://www.jacksonville.gov/getContentAsset/f2c6099d-cdf0-40da-b6a9-43e4c734282e/135b97c9-84fa-4e82-b956-0fbccec4aa1f/LDPM-Vol2-EFF-2026-01-30-CLEAN-ADA-508.pdf?language=en", "landing_page_url": "https://www.sjrwmd.com/documents/permitting/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "palm-coast-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 6, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:40:04.188Z", "enrich_model": "composer-2.5:run-9f603590-638b-4829-a2de-5488fc86cf49", "enrich_notes": "Corpus is Jacksonville LDPM Vol. 2 (green infrastructure and detention sections) used as Palm Coast / SJRWMD municipal proxy. Swale and shallow bioretention both require 72-hour recovery of standing/ponding water. Swale minimum bottom width 2 ft; longitudinal slope allowed 0.5–3% (no single design value). Bioretention and swale WQ credits cite SHWL at least 6 in below swale bottom or planting/sorption media bottom; bioretention also states SHWL at least 0.5 ft below surface ponding area bottom. Wet detention sizing example uses SJRWMD residence-time equations and 1-in / 2.5-in treatment-volume illustration, not a codified WQv depth. Basin infiltration design uses safety factor of 2 on double-ring infiltrometer tests (Section 3.7).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pasadena-tx", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pasadena-tx/", "data_url": "https://stormwateratlas.com/data/manuals/pasadena-tx.json", "document_metadata": { "jurisdiction_name": "City of Pasadena", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Harris County Low Impact Development & Green Infrastructure Design Criteria for Storm Water Management", "version_or_edition": "Adopted April 2011", "adoption_or_effective_date": "2011-04-01", "last_revised_date": "2011-04-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Projects exceeding one acre require a Storm Water Quality (SWQ) Permit and SWQMP; treat the first 1 inch of runoff. LID IMPs may satisfy quality and detention credits per Harris County criteria. Conventional gravity detention minimum rate 0.55 ac-ft per acre.", "peak_flow_calculation_method": [ "Detention and hydrograph matching per HCPID-AED / HCFCD requirements", "Minimum detention 0.55 ac-ft/acre for gravity systems" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention systems", "Vegetated swale / bioswale", "Permeable pavement", "Rainwater harvesting", "Green roof", "Filter strips / tree box filters" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "by November 1, 2011, as a part of the Harris County Public Infrastructure Department Architecture & Engineering Division (HCPID-AED) and Harris County Flood Control District (HCFCD) Storm Water Management Programs. This requirement is specifically located in the Bacteria Reduct", "page_or_section": "pp. 3–4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat the first 1 inch of runoff", "page_or_section": "Harris County LID/GI Design Criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = depth of runoff to treat (1\" under these guidelines)", "page_or_section": "3.5.2 Sizing a Bioretention System, page 15" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treatment of the first 1\" of runoff", "page_or_section": "Table 6 / 3.5.1 Requirements, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Ponding duration not to exceed 24 hours", "page_or_section": "Table 6 Surface Ponding, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The Bioretention system should be designed so that surface ponding does not exceed 24 hours", "page_or_section": "1.5 Bioretention Systems, page 30" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "must be designed to incorporate an underdrain/subsurface detention or retention system with the capacity to drain the surface of the system within 24 hours", "page_or_section": "1.6.1 Underdrain, page 34" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "meet Harris County minimum 30\"/hour Infiltration rate requirements", "page_or_section": "Appendix B, page 42" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "must provide a minimum safety factor of 2", "page_or_section": "3.5.3 Engineered Soil Media, page 15" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Harris County LID/GI SWQ criteria (Houston metro pattern). Prefer city-specific drainage criteria PDF if found.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://oce.harriscountytx.gov/Portals/43/Documents/Publications/SWQ_LID_design_criteria.pdf", "landing_page_url": "https://www.pasadenatx.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "pasadena-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 30, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:40:22.302Z", "enrich_model": "composer-2.5:run-280f7a09-1e71-452d-9d90-bd42252bb97f", "enrich_notes": "Harris County LID criteria: Vwq uses P=1 in; engineered soil design uses safety factor of 2 on infiltration rate. LID detention goal drain within 72 hours (general detention bullet). Bioretention surface ponding 2 ft (2-yr) and 4 ft (100-yr) in Table 6; general narrative 12–24 in ponding. Media depth typically 1.5–2.0 ft (sizing) and 18–24 in (vegetation); lifts max 12 in. Permeable pavement surface drain within 24 h; underdrain/storage may use impermeable liner. Extensive green roof growth media stated as 4–8 in (range). Appendix B infiltrometer pass/fail uses media-depth-specific drawdown minutes, not site hours.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "paterson-nj", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/paterson-nj/", "data_url": "https://stormwateratlas.com/data/manuals/paterson-nj.json", "document_metadata": { "jurisdiction_name": "City of Paterson", "jurisdiction_level": "municipality", "state_code": "NJ", "document_title": "New Jersey Stormwater BMP Manual / N.J.A.C. 7:8 (city MS4 follows NJDEP standards)", "version_or_edition": "Chapter 5: July 2023; Chapter 9.7: January 2026", "adoption_or_effective_date": "2023-07", "last_revised_date": "2026-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5). NRCS methodology computes WQDS runoff volume, peak rate, and hydrograph; BMPs such as small-scale bioretention must store/treat the entire WQDS volume.", "peak_flow_calculation_method": [ "USDA NRCS methodology (NRCS Runoff Equation and Dimensionless Unit Hydrograph)", "NRCS Curve Number (CN) method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Small-scale green infrastructure BMPs", "Small-scale bioretention systems", "Small-scale infiltration basins", "Green roofs", "Pervious paving systems", "Grass swales", "Cisterns", "Green Infrastructure MTDs / MTDs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Paterson MS4 follows NJDEP Stormwater BMP Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — NJDEP BMP Manual / N.J.A.C. 7:8", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQDS: 1.25 inches of rain falling nonuniformly over 2 hours", "page_or_section": "N.J.A.C. 7:8-5.5 / Ch.5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The capacity of the underdrain must be sufficient to allow the system to drain within 72 hours", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 74 (paterson-nj-c0092)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the small-scale bioretention system with underdrain is installed in an area subject to pedestrian traffic, the drain time should be reduced to 24 hours", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 74 (paterson-nj-c0092)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table (SHWT) must be at least 1 foot below the bottom of the gravel layer", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 74 (paterson-nj-c0092)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the elevation difference between the basin bottom and the SHWT is 5 ft, which is greater than the 2 ft mimimum separation requirement", "page_or_section": "Chapter 9.7 Example 3, page 87 (paterson-nj-c0105)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Since the soil bed must support the growth of the tree, the minimum depth of 18 inches may not be sufficient", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 79 (paterson-nj-c0097)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The water depth above the soil bed should not exceed the maximum design depth of 12 inches", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 81 (paterson-nj-c0099)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "For the WQDS, the maximum depth of runoff is 18 inches at the down-gradient end of a sloped-bottom system", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 79 (paterson-nj-c0097)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "In sloped-bottom systems, the maximum longitudinal slope is 10%", "page_or_section": "Green Infrastructure BMPs, Chapter 9.7, page 79 (paterson-nj-c0097)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The 72 hour maximum has not been exceeded, meaning the procedure may be continued", "page_or_section": "Chapter 5, page 44 (paterson-nj-c0054)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NJDEP Stormwater BMP Manual / N.J.A.C. 7:8.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dep.nj.gov/wp-content/uploads/stormwater/bmp/njswbmp-chapter-9.7-small-scale-bioretention-systems-january-2026.pdf", "landing_page_url": "https://dep.nj.gov/stormwater/stormwater-management/bmp-manual/", "retrieved_at": "2026-08-10T09:45:18.908Z", "original_filename": "paterson-nj.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 10, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "swale" ], "enriched_at": "2026-08-13T09:41:05.985Z", "enrich_model": "composer-2.5:run-994da52c-591e-42d2-bd02-b49db54a133f", "enrich_notes": "Atlas WQDS 1.25 in is not stated in excerpts. SHWT: 1 ft below gravel layer (underdrain bioretention); Example 3 cites 2 ft minimum separation for infiltration rain garden. Bioretention swale WQDS max runoff depth 18 in at down-gradient end (distinct from 12 in max ponding above soil bed in planter example). Pedestrian areas: 24 hr drain time for underdrain bioretention vs 72 hr general maximum. Infiltration period cap 72 hr referenced in Chapter 5 mounding examples.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pearland-tx", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pearland-tx/", "data_url": "https://stormwateratlas.com/data/manuals/pearland-tx.json", "document_metadata": { "jurisdiction_name": "City of Pearland", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Harris County Low Impact Development & Green Infrastructure Design Criteria for Storm Water Management", "version_or_edition": "Adopted April 2011", "adoption_or_effective_date": "2011-04-01", "last_revised_date": "2011-04-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Projects exceeding one acre require a Storm Water Quality (SWQ) Permit and SWQMP; treat the first 1 inch of runoff. LID IMPs may satisfy quality and detention credits per Harris County criteria. Conventional gravity detention minimum rate 0.55 ac-ft per acre.", "peak_flow_calculation_method": [ "Detention and hydrograph matching per HCPID-AED / HCFCD requirements", "Minimum detention 0.55 ac-ft/acre for gravity systems" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention systems", "Vegetated swale / bioswale", "Permeable pavement", "Rainwater harvesting", "Green roof", "Filter strips / tree box filters" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "by November 1, 2011, as a part of the Harris County Public Infrastructure Department Architecture & Engineering Division (HCPID-AED) and Harris County Flood Control District (HCFCD) Storm Water Management Programs. This requirement is specifically located in the Bacteria Reduct", "page_or_section": "pp. 3–4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat the first 1 inch of runoff", "page_or_section": "Harris County LID/GI Design Criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = depth of runoff to treat (1\" under these guidelines)", "page_or_section": "3.5.2 Sizing a Bioretention System, page 15" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treatment of the first 1\" of runoff", "page_or_section": "Table 6 / 3.5.1 Requirements, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "For LID projects, the goal is to drain within 72 hours, unless pre-existing conditions are shown to take longer.", "page_or_section": "Part II § Detention, page 7" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The Engineered Soil Media depth should be determined based on the mature root depth of the selected vegetation, (typically between 18 and 24 inches).", "page_or_section": "1.5.2 Engineered Soil Media, page 31" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum surface ponding depth of 2ft for the 2yr event and 4ft for the 100yr event.", "page_or_section": "Table 6 Surface Ponding, page 14" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "surface ponding does not exceed 24 hours", "page_or_section": "1.5.1 Design Considerations, page 30" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "meet Harris County minimum 30\"/hour Infiltration rate requirements, of bioretention media", "page_or_section": "Appendix B, page 42" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention & Engineered Soil", "page_or_section": "Table 1 Acceptable LID IMPs, page 7" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated Swale", "page_or_section": "Table 1 Acceptable LID IMPs, page 7" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Permeable Pavement", "page_or_section": "Table 1 / 1.6 Permeable Pavement Systems, pages 7, 33" }, { "field": "practice_mentions.green_roof", "excerpt": "1.9 Green Roof", "page_or_section": "page 35" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Harris County LID/GI SWQ criteria (Houston metro pattern). Prefer city-specific drainage criteria PDF if found.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://oce.harriscountytx.gov/Portals/43/Documents/Publications/SWQ_LID_design_criteria.pdf", "landing_page_url": "https://www.pearlandtx.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "pearland-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 30, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:41:40.056Z", "enrich_model": "composer-2.5:run-66e8a281-6d48-4ff7-a397-705deae69aec", "enrich_notes": "Harris County Pearland LID criteria: WQv uses P=1 inch; bioretention sizing uses Df typically 1.5–2.0 ft and ponding H in feet; infiltration design requires safety factor of 2 on media rate; Appendix B as-built test requires minimum 30 in/hr media infiltration; surface ponding must not exceed 24 hours (bioretention/permeable pavement); LID detention goal drain within 72 hours; 2-yr event max bioretention surface ponding 2 ft (100-yr 4 ft).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pensacola-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pensacola-fl/", "data_url": "https://stormwateratlas.com/data/manuals/pensacola-fl.json", "document_metadata": { "jurisdiction_name": "City of Pensacola (NWFWMD criteria)", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "NWFWMD Environmental Resource Permit Applicant’s Handbook Volume II (design standards)", "version_or_edition": "June 28, 2024", "adoption_or_effective_date": "2024-06-28", "last_revised_date": "2024-06-28", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "NWFWMD ERP AH Vol II stormwater quality criteria (Parts II/IV/V) including retention system treatment volume and additional quality standards. Quantity/flood criteria include 10-year floodplain storage and 100-year floodway conveyance limits.", "peak_flow_calculation_method": [ "Stormwater quantity rate and volume controls (Part III)", "Retention / detention routing", "Floodplain / floodway conveyance checks" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems", "Detention systems", "On-line and off-line stormwater systems", "Stormwater quantity / flood control facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Pensacola / NWFWMD geographic boundaries", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT’S HANDBOOK VOLUME II", "page_or_section": "Title" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The retention system must provide the capacity for the appropriate treatment volume of stormwater specified in Section 5.2 of this Volume within 72 hours following a storm event assuming average antecedent moisture conditions.", "page_or_section": "5.0.3 Recovery Time, page 36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The system shall be designed to recover the required treatment volume of stormwater runoff within 72 hours following a storm event assuming average antecedent moisture conditions.", "page_or_section": "5.1.3 Recovery Time, page 40" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The exfiltration trench system shall be designed so that the invert elevation of the trench is at least two feet above the seasonal high ground water table elevation", "page_or_section": "5.1.8 Ground Water Table, page 42" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The average length to width ratio of the pond must be at least 2:1.", "page_or_section": "5.2.8 Pond Configuration, page 50" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The outfall structure shall be designed to drawdown one-half the required treatment volume between 48 and 60 hours.", "page_or_section": "5.2.3 Recovery Time, page 43" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipal map coverage via NWFWMD ERP AH Vol II. Canonical special_district record: fl-nwfwmd-erp-ah2. Regional NWFWMD AH Vol II for Pensacola MS4 — confirm city-specific amendments.", "fields_not_found": [] }, "source": { "document_url": "https://nwfwater.com/wp-content/uploads/2024/07/AHII-nwfwmd-FINAL-2024.pdf", "landing_page_url": "https://nwfwater.com/", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "pensacola-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:42:11.095Z", "enrich_model": "composer-2.5:run-fb5235f1-6f40-4015-ac3c-0de2d518d671", "enrich_notes": "Treatment volume sizing references NWFWMD ERP AH Volume I Sections 8.3 and 9 (efficiency-based), not a fixed WQv depth in inches. Wet detention drawdown for half the treatment volume is specified as 48–60 hours (single hour value not given). Exfiltration safety factor may require half the design infiltration rate or 36-hour drawdown when factor of two is applied. Appendix B-2 filter criteria include 2 ft separation above gravel pack and 6 in. average gravel-pack thickness (not mapped to canonical numeric fields). Swale sizing references 3-year, 1-hour storm infiltration, not bottom width or longitudinal slope percent.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "peoria-il", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/peoria-il/", "data_url": "https://stormwateratlas.com/data/manuals/peoria-il.json", "document_metadata": { "jurisdiction_name": "City of Peoria", "jurisdiction_level": "municipality", "state_code": "IL", "document_title": "Unified Stormwater Ordinance / Manual of Practice Chapter 17", "version_or_edition": "September 2012", "adoption_or_effective_date": null, "last_revised_date": "2012-09", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 10, 100 ], "water_quality_volume_method": "Water Quality Volume = volume necessary to collect 100% of runoff from a specified event; detain ≥24 hours from 1-year HWL (detention) or 2-year HWL (certain BMPs) until complete drainage. Release-rate design for Class 2 grading/drainage: 1-year (≤0.08 cfs/acre with 24-hr detention), 10-year 0.08 cfs/acre, 100-year 0.30 cfs/acre (Illinois River direct discharges exempt from 10-/100-year limits but still need 24-hr 1-year WQ detention).", "peak_flow_calculation_method": [ "Release rates (cfs/acre) for 1-/10-/100-year", "Rational Formula (minor systems ≤10–100 acres)", "Hydrograph / reservoir routing for detention", "IDOT Drainage Manual methods (as modified)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet bottom detention basins", "Wetland basins", "Dry basins", "Infiltration trenches", "Swales / native landscaping", "Porous pavement", "Other BMPs meeting WQv detention" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "City of Peoria Manual of Practice Chapter 17 September 2012", "page_or_section": "Headers" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume means the volume necessary to collect 100 percent of the runoff generated from a specified event. This volume shall be detained for a period not less than 24 hours", "page_or_section": "Definitions §120" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "10-year 0.08 100-year 0.30 ... 1-year release rate ... not be greater than 0.08 cfs/acre", "page_or_section": "Section Three, Article II.B Release Rates" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Stormwater shall not be allowed to stand more than seventy-two (72) hours over eighty (80) percent of the dry basin's bottom area for the maximum design event.", "page_or_section": "Section Three, Article III. – Detention System Design Criteria, Infiltration Practices (page 56)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of infiltration basins or trenches shall be a minimum of three (3) feet above the seasonally high groundwater and bedrock level if practicable.", "page_or_section": "Section Three, Article III. – Detention System Design Criteria, Infiltration Practices (page 56)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume means the volume necessary to collect 100 percent of the runoff generated from a specified event.", "page_or_section": "Section One, Article I. Definitions, item 120 (page 17)" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention areas are landscaping features adapted to provide on-site treatment of storm water runoff.", "page_or_section": "Section Three, Article I. D. Infiltrating Runoff On-Site (page 46)" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Storm water wetlands (a.k.a. constructed wetlands) are structural practices similar to wet detention ponds that incorporate wetland plants into the design.", "page_or_section": "Section Three, Article I. C. (page 45)" }, { "field": "practice_mentions.swale", "excerpt": "These BMPs shall be designed to follow criteria in the Illinois Urban Manual.", "page_or_section": "Section Three, Article II. H. Vegetated Filter Strips and Swales (page 50)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://www.peoriagov.org/DocumentCenter/View/2575", "landing_page_url": "https://www.peoriagov.org/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "peoria-il.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:42:39.157Z", "enrich_model": "composer-2.5:run-e09d51f2-00ff-4e62-af7d-b5be11a1e20b", "enrich_notes": "Water Quality Volume is defined as 100% of runoff from a specified event with minimum 24-hour detention from 1-year HWL (detention) or 2-year HWL (certain BMPs) until complete drainage; no WQ rainfall depth in inches is stated in the excerpts. Swales and filter strips defer to Illinois Urban Manual. Infiltration BMPs reference Illinois Urban Manual; max standing 72 hours on 80% of dry basin bottom; 3 ft SHWT separation for infiltration basin/trench bottoms.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "phoenix-az", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/phoenix-az/", "data_url": "https://stormwateratlas.com/data/manuals/phoenix-az.json", "document_metadata": { "jurisdiction_name": "City of Phoenix", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "City of Phoenix Stormwater Policies and Standards Manual", "version_or_edition": "2nd Edition, April 2011", "adoption_or_effective_date": "2011-04", "last_revised_date": "2011-04", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Retain the 100-year, 2-hour storm on site; when retention is waived, meet First Flush by retaining or treating the first 0.5 inch of direct runoff (VFF = C × P × A / 12 with C = 1.00 and P = 0.5 inch).", "peak_flow_calculation_method": [ "Rational Method", "HEC-1", "NRCS Type II distribution", "Maricopa County Drainage Design Manual procedures" ], "required_hydrologic_hydraulic_software": [ "Phoenix-DDMSW (Drainage Design Management System for Windows)" ], "approved_bmp_categories": [ "On-Lot Retention Basins", "Detention Facilities", "Sediment Basins", "Dry Wells", "Open Channels", "Storm Drains", "Erosion Control Measures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Phoenix", "page_or_section": "Cover / Section 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Phoenix", "page_or_section": "Cover / Section 1" }, { "field": "document_metadata.state_code", "excerpt": "Arizona municipalities within the urbanized area were brought into the municipal stormwater permitting program through Phase II of the Federal stormwater program", "page_or_section": "Section 3.4, Page 3-15" }, { "field": "document_metadata.document_title", "excerpt": "City of Phoenix Stormwater Policies and Standards Manual", "page_or_section": "Table of Contents" }, { "field": "document_metadata.version_or_edition", "excerpt": "2nd Edition April 2011", "page_or_section": "Revisions, Page i" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "2nd Edition April 2011", "page_or_section": "Revisions, Page i" }, { "field": "document_metadata.last_revised_date", "excerpt": "Updated 4/2011", "page_or_section": "Revisions, Page i" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "These policies, together with the Phoenix City Codes, the Phoenix Drainage Standards (Chapter 6), and the Maricopa County Drainage Design Manuals, define the criteria and procedures to be used for storm water management and drainage design in the City of Phoenix.", "page_or_section": "Section 3.1, Page 3-13" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Street Storm Drains 2-year... Storm Water Storage Facilities 100-year, 2-hour rainfall... Post-development peak discharges shall not exceed pre-development peak discharges for the 2-, 10-, and 100-year storm events.", "page_or_section": "Table 6.2.1 and Section 6.8.3, Pages 6-55 to 6-89" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All new developments shall make provisions to retain the storm water runoff from a 100-year, 2-hour duration storm... This minimum standard is \"First Flush\", and consists of retaining or treating the first 0.5 inch of direct runoff from a storm event.", "page_or_section": "Sections 6.8.1 and 6.8.3, Pages 6-88 to 6-89" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Peak discharges and runoff volumes shall be calculated in accordance with the procedures in the Drainage Design Manuals... Runoff calculations for the sizing of storm drain catch basin inlets and connector pipes shall be based on the Rational formula.", "page_or_section": "Sections 3.3.1, 6.3.2, and 8.3, Pages 3-15, 6-59, 8-121" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The website contains the following documents relating to this manual: ... the City of Phoenix stormwater design software – Drainage Design Management System for Windows (Phoenix – DDMSW)", "page_or_section": "Section 7 and Section 8.1, Pages 7-119 to 8-121" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "All new developments shall make provisions to retain the storm water runoff from a 100-year, 2-hour duration storm... Sedimentation basins as required per Section 6.10 shall be located at the upstream (inlet) end of stormwater storage facilities.", "page_or_section": "Sections 6.8 and 6.10, Pages 6-88 to 6-90" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "retaining or treating the first 0.5 inch of direct runoff from a storm event", "page_or_section": "6.8.3 First Flush, page 89" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = first 0.5 inch of direct runoff", "page_or_section": "6.8.3 First Flush, page 89" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the stored runoff shall be emptied completely from the facility within 36 hours after the runoff event has ended", "page_or_section": "6.8.10 Basin Drain Time, page 92" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "shall drain the 100-year (design) storm water storage volume within 36 hours, but not less than 24 hours", "page_or_section": "6.8.10 Basin Drain Time, page 92" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "minimum bottom widths shall be four feet for ditches adjacent and parallel to streets or access roads", "page_or_section": "6.6.19 Ditches and Swales, page 87" }, { "field": "practice_mentions.swale", "excerpt": "Roadside ditches and swales that are intended to convey 100-year flows less than 100 cfs shall be no deeper than two feet", "page_or_section": "6.6.19 Ditches and Swales, page 87" }, { "field": "practice_mentions.extended_detention", "excerpt": "In the special case when a detention facility is allowed, the requirement to retain the 100-year, 2-hour runoff volume may be waived", "page_or_section": "6.8.3 First Flush, page 89" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Required retention basin volume shall be obtained by using the following equation", "page_or_section": "6.8.4 Retention Volume, page 90" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Phoenix manual clearly defines 100-year 2-hour retention, First Flush 0.5-inch policy, Rational/HEC-1 hydrology, and Phoenix-DDMSW as the city drainage software.", "fields_not_found": [] }, "source": { "document_url": "https://www.phoenix.gov/content/dam/phoenix/streetssite/documents/swpolicy.pdf", "landing_page_url": "https://www.phoenix.gov/streets/stormwater", "retrieved_at": "2026-08-08T01:05:00.000Z", "original_filename": "phoenix-az.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 36, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 48, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T09:44:37.571Z", "enrich_model": "composer-2.5:run-1c6406d7-28e9-4231-b6ba-1dba05febb5c", "enrich_notes": "Phoenix primary retention is 100-year 2-hour storm volume (V=C×P×A/12); First Flush uses C=1.0 and P=0.5 inch when retention is waived. Storage basins must drain fully within 36 hours (bleed-off primary outlet sized for 24–36 hr). Roadside ditches/swales for <100 cfs 100-year flows max 2 ft deep; min bottom width 4 ft parallel to streets. Parking lot ponding max 6 in.; street ponding max 0.5 ft where allowed.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pierre-sd", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pierre-sd/", "data_url": "https://stormwateratlas.com/data/manuals/pierre-sd.json", "document_metadata": { "jurisdiction_name": "City of Pierre", "jurisdiction_level": "municipality", "state_code": "SD", "document_title": "SDDOT Erosion and Sediment Control and Stormwater Management Course Manual (partial)", "version_or_edition": "Revised October 2024", "adoption_or_effective_date": null, "last_revised_date": "2024-10", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Erosion Control BMPs", "Sediment Control BMPs", "Slope / channel velocity controls", "Stabilized construction entrance" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Pierre — partial coverage via SDDOT ESC/stormwater course manual (city design PDF 403)", "page_or_section": "Coverage note" }, { "field": "practice_mentions.swale", "excerpt": "they improve the efficiency of other sediment controls, such as vegetated swales, filter strips, or infiltration devices", "page_or_section": "page 16, Slope Flow Control/Stormwater Runoff Management" }, { "field": "practice_mentions.swale", "excerpt": "Check Dams – are small dams constructed in an open channel, swale, or ditch.", "page_or_section": "page 17, Channel Velocity Control" }, { "field": "practice_mentions.swale", "excerpt": "structural stormwater management practices such as stormwater ponds, open vegetated swales, natural depressions to allow infiltration of runoff onsite", "page_or_section": "page 95, 5.3 SWPPP Contents – Post-Construction Stormwater Management" }, { "field": "practice_mentions.wet_pond", "excerpt": "A diversion ditch is constructed to divert the stormwater runoff away from a slope or active construction area and into a stabilized outlet or a sediment trap or pond.", "page_or_section": "page 16" }, { "field": "practice_mentions.wet_pond", "excerpt": "structural stormwater management practices such as stormwater ponds, open vegetated swales", "page_or_section": "page 95, Post-Construction Stormwater Management" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "vegetated swales, filter strips, or infiltration devices, which depend on sheet flow to operate properly", "page_or_section": "page 16, Level Spreader" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "natural depressions to allow infiltration of runoff onsite", "page_or_section": "page 95, Post-Construction Stormwater Management" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "ESC-focused state course manual — not a full municipal post-construction design manual.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://dot.sd.gov/media/kywakwy4/escontrolsw.pdf", "landing_page_url": "https://danr.sd.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "pierre-sd.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:46:34.505Z", "enrich_model": "composer-2.5:run-e4658f2d-c0cb-422c-95df-e34e9efc12b9", "enrich_notes": "SDDOT/DANR construction ESC and SWPPP course material tied to the South Dakota construction general permit. Excerpts cover erosion/sediment BMPs, SWPPP, inspection, dewatering (53 mg/L TSS limit), and post-construction narrative (ponds, vegetated swales, onsite infiltration) without numeric SCM sizing, WQv depth, drawdown, or media dimensions.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pittsburgh-pa", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pittsburgh-pa/", "data_url": "https://stormwateratlas.com/data/manuals/pittsburgh-pa.json", "document_metadata": { "jurisdiction_name": "City of Pittsburgh", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Stormwater Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Volume Control (Section 2.2.a): stormwater facilities shall capture at least the first two (2) inches of runoff; volume control tied to managing runoff from the 95th percentile storm (§1303.03). Includes water quality treatment, volume control offsets/incentives. Rate Control (Section 2.2.b) uses NOAA Atlas 14 climate-change design rain events.", "peak_flow_calculation_method": [ "Rate control modeling requirements (Section 2.2.b)", "NOAA Atlas 14 and climate change design rain events", "Rate control points of interest" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green roofs / rain gardens", "Volume control BMPs", "Rate control facilities", "Stormwater BMP design standards (Section 4)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Pittsburgh", "page_or_section": "Section 1.1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Pittsburgh", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Pennsylvania / Title Thirteen", "page_or_section": "Introduction" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER DESIGN MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Title Thirteen Stormwater Management", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater facilities shall capture at least the first two (2) inches of runoff", "page_or_section": "Section 2.2.a Volume Control" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "NOAA Atlas 14 and Climate Change Design Rain Events", "page_or_section": "Section 2.2.b.i" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "green roofs and rain gardens", "page_or_section": "Section 2.2.a" }, { "field": "wqv_depth_inches", "excerpt": "stormwater facilities shall capture at least the first two (2) inches of runoff", "page_or_section": "Atlas context — Volume Control (Section 2.2.a)" }, { "field": "shwt_separation_inches", "excerpt": "must show at least 2 ft. of separation (measured from the bottom of the basin, or underdrain, if present) from the seasonal high groundwater level table", "page_or_section": "page 62 — Groundwater" }, { "field": "shwt_separation_inches", "excerpt": "The bottom underdrain invert elevation of the infiltrating BMPs must not be within two (2) feet of bedrock or the seasonal high groundwater.", "page_or_section": "page 89 — Section 4.2.a.ii" }, { "field": "length_to_width_ratio", "excerpt": "Basins must have a length-to-width ratio of at least 2:1 to the extent possible.", "page_or_section": "page 125 — Ponds and Wet Basins, General B" }, { "field": "mtd_verification_program", "excerpt": "filtration technologies must demonstrate pollutant removal performance at an equivalent level required by New Jersey Corporation for Advanced Technology (NJCAT) certification and the Technology Assessment Protocol-Ecology (TAPE) developed by the Washington State Department of Ecology", "page_or_section": "page 146 — Section 4.4 filtration / manufactured treatment" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Pittsburgh Stormwater Design Manual; 2-inch / 95th percentile volume control confirmed.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://engage.pittsburghpa.gov/download_file/2830/541", "landing_page_url": "https://www.pittsburghpa.gov/Business-Development/Zoning/Plan-Reviews-and-Notices/Environmental-Review/Stormwater", "retrieved_at": "2026-08-10T08:30:22.061Z", "original_filename": "pittsburgh-pa.pdf" }, "design_parameters": { "wqv_depth_inches": 2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "NJCAT; TAPE", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:47:34.341Z", "enrich_model": "composer-2.5:run-fe7968c8-dc9d-44f3-9b6d-b3d65e4099ce", "enrich_notes": "Atlas/review context states volume control captures the first 2 inches of runoff (95th percentile); not repeated in corpus chunks. Infiltration BMPs are infeasible where tested rates are below 0.2 in/hr (Section 3.4 reference). Wet pond/wetland temporary storage typically drains in less than 72 hours; pool zone standing depth is 2–6 ft (8 ft max)—not a single permanent-pool design depth. Table 3.4 lists roof slope >8% as a green-roof siting constraint, not a design slope.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "plano-tx", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/plano-tx/", "data_url": "https://stormwateratlas.com/data/manuals/plano-tx.json", "document_metadata": { "jurisdiction_name": "City of Plano", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Drainage Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Section 5.0 Maintenance, Permitting, and Stormwater Quality; Stormwater Quality Plan requirements. Detention storage calculation in Section 3.9.", "peak_flow_calculation_method": [ "Rational Method runoff calculation (Form C)", "Detention storage calculation (Section 3.9.1)", "100-year fully developed floodplain context for floodplain definition" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention / stormwater storage", "Storm drainage facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Plano (City)", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Plano", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "Highway Research Program • NCTCOG: North Central Texas Council of Governments • NRCS: National Resources Conservation Service • TAC: Texas Administrative Code • TCEQ: Texas Commission on Environmental Quality • TxDOT: Texas Department of Transportation • USACE: Unite", "page_or_section": "p. 20" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Design Manual / Storm Drainage Design Manual", "page_or_section": "Title / purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "fully developed 100-year water surface elevation", "page_or_section": "Definitions" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater Quality Plan", "page_or_section": "Section 5.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational Method Runoff Calculation / Detention Storage Calculation", "page_or_section": "Form C / Section 3.9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Storage and Detention", "page_or_section": "Section 3.9" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The bottom of the basin shall have a minimum grade of 1%, although swales may have minimum grades of 0.5%.", "page_or_section": "Section 3.9.2 Pond and Spillway Geometry, page 3-26 (page 64)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry detention basins are sized to temporarily store the volume of runoff required to provide flood protection up to the flood mitigation storm, if required.", "page_or_section": "Section 3.9.2, page 3-26 (page 64)" }, { "field": "practice_mentions.swale", "excerpt": "The Engineer may utilize swales to redirect flows.", "page_or_section": "Section 1.5.3 Site Grading Plans, page 1-11 (page 23)" }, { "field": "practice_mentions.wet_pond", "excerpt": "Easements for stormwater controls, including detention basins, sediment traps, and retention ponds, shall be negotiated between the City and the developer", "page_or_section": "Section 1.5.3 Other Stormwater Facilities, page 1-13 (page 25)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Plano storm drainage design manual; edition date not prominent in extract. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://content.civicplus.com/api/assets/tx-plano/a66735c2-e8bd-4348-ad5f-fb5dedebdaef/final-city-of-plano-storm-drainage-design-manual-1-.pdf?scope=all&sq=1c8352d3-e41e-89e7-c087-e050ad0bd558", "landing_page_url": "https://www.plano.gov/", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "plano-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:48:01.897Z", "enrich_model": "composer-2.5:run-9f75b2d9-dd8b-4018-8068-16f51e94c798", "enrich_notes": "Provided excerpts emphasize storm drainage, easements, inlets, channels, and dry detention pond geometry (Section 3.9.2). No explicit WQv runoff depth, infiltration rates, bioretention/permeable pavement/green roof specs, or manufactured-treatment verification programs appear. P2 is defined as 2-year 24-hour rainfall (4.1 in)—rainfall depth, not WQv treatment depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "port-st-lucie-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/port-st-lucie-fl/", "data_url": "https://stormwateratlas.com/data/manuals/port-st-lucie-fl.json", "document_metadata": { "jurisdiction_name": "City of Port St. Lucie", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "SFWMD Environmental Resource Permit Applicant's Handbook Volume II (Basis of Review)", "version_or_edition": "Effective July 4, 2010 (draft ERP Vol II mirror)", "adoption_or_effective_date": "2010-07-04", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "SFWMD ERP AH Vol II: wet detention volume for the first inch of runoff from the developed project (or 2.5 in over the basin for projects with ≥50% impervious / special cases per rule); dry detention = 75% of wet; retention = 50% of wet. Quantity: off-site discharge typically based on 3-day / 25-year storm unless local criteria are more stringent; 100-year / 3-day considered for flood protection / finished floors.", "peak_flow_calculation_method": [ "3-day / 25-year off-site discharge (default)", "100-year / 3-day flood considerations", "Retention / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Dry retention / detention", "Exfiltration trenches", "Swales / pretreatment", "Other SFWMD-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Port St. Lucie is within SFWMD and follows ERP Applicant's Handbook Vol II", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet detention volume shall be provided for the first inch of runoff", "page_or_section": "SFWMD Vol II water quality criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project, or the total runoff of 2.5 inches times the percentage of imperviousness, whichever is greater.", "page_or_section": "4.2.1 Volumetric Requirements, page 17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The required water quality system for one inch of runoff detention or one half inch of runoff retention in the master system for the total developed site.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Residential projects shall have systems with the calculated ability to discharge by surface flow or subsurface percolation at least 3/8 inch per day during or subsequent to the storm of the allowable discharge frequency and duration, so that lowering of the water surface elevations within the water management system to the maximum depth compatible with the environmental protection or other constraints as described in 3.10, will occur in 12 days or less.", "page_or_section": "3.9 Minimum Drainage (a), page 14" }, { "field": "practice_mentions.swale", "excerpt": "Onsite works such as swales and dikes shall be used to allow the passage of drainage from offsite areas to downstream areas.", "page_or_section": "3.8 Offsite Lands, page 14" }, { "field": "practice_mentions.swale", "excerpt": "Retention, detention, or both retention and detention in the overall system, including swales, lakes, canals, greenways, etc.", "page_or_section": "4.2.1 Volumetric Requirements (a), page 17" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.3.1 Description, page 26" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The individual sites must provide the remainder (2.5\" x % impervious - one inch) which may be in exfiltration trench.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "1 hour (parking lots served by exfiltration systems)", "page_or_section": "3.5 Flood Protection of Roads and Parking Lots (a), page 13" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project", "page_or_section": "4.2.1 Volumetric Requirements, page 17" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry retention/detention areas shall have mechanisms for returning the groundwater level in the area to the control elevation. The bleed-down rate for these systems is the same as in section 5.2.(a), herein.", "page_or_section": "5.3.3 Dry Retention/Detention Areas (a), page 26" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Man-made or natural depressional areas where the basin bottom is graded flat and turf is established to promote infiltration and stabilize the basin slopes", "page_or_section": "5.3.1 Description, page 26" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SFWMD ERP AH Vol II. Prefer city-specific drainage criteria if a durable public PDF appears.", "fields_not_found": [] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/draft_erp%20vol%20ii%20swerp%20ii_2104_10.pdf", "landing_page_url": "https://www.sfwmd.gov/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "port-st-lucie-fl.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 288, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:48:32.724Z", "enrich_model": "composer-2.5:run-ff6468f8-9824-49b8-8f4c-78f3074ba97a", "enrich_notes": "SFWMD ERP AH Vol II (Aug 2014) applies via municipality. WQ wet detention: first 1 in of runoff or 2.5 in × % impervious (greater). Master-planned commercial subdivisions: 1 in detention or 0.5 in retention in master system; remainder (2.5×% impervious − 1 in) may be exfiltration trench on lots; master cannot use exfiltration trench. Residential minimum drainage: ≥3/8 in/day surface or subsurface discharge so WSEL lowers within 12 days. Detention/control excavations max 6 ft below natural ground. Subsurface exfiltration per applicant test data; Dade County DER M and FDOT cited as references.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "portland-me", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/portland-me/", "data_url": "https://stormwateratlas.com/data/manuals/portland-me.json", "document_metadata": { "jurisdiction_name": "City of Portland", "jurisdiction_level": "municipality", "state_code": "ME", "document_title": "Maine Stormwater Management Design Manual, Volume III", "version_or_edition": "May 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-05-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25 ], "water_quality_volume_method": "Treat the first 1 inch of runoff from impervious surfaces and 0.4 inch from landscaped areas.", "peak_flow_calculation_method": [ "Rational Method", "SCS TR-20", "SCS TR-55" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Detention Basins", "Wet Ponds", "Vegetated Buffers", "Infiltration / Filtration BMPs", "LID Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Portland ME MS4 follows Maine Stormwater Design Manual Vol III", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "An underdrained soil filter must detain and filter a runoff volume equal to 1.0 inch times the subcatchment's impervious area plus 0.4 inch times the subcatchment's landscaped developed area.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A filter basin must drain dry in no less than 24 and no more than 48 hours.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the constructed basin, including any underdrain soil filters should be one (1) foot above the seasonal high groundwater table", "page_or_section": "Chapter 3, page 16" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the underdrained soil filter should be a minimum of 18 inches above the seasonal high groundwater table or bedrock", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The soil filter over the gravel underdrain pipe bedding must be at least 18 inches deep", "page_or_section": "Chapter 7.2, page 58" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The peak water quality storage depth should not exceed 6 inches over a bioretention basin filter.", "page_or_section": "Chapter 7.2, page 57" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Provide a long and narrow basin shape, with a minimum 2:1 length to width ratio (3:1 is best).", "page_or_section": "Chapter 4 Wetponds, page 22" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Roof Slope: A minimum slope of 2% is considered normal for extensive and simple intensive greening.", "page_or_section": "Chapter 7.6, page 77" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "The target detention time for the treatment volume should be between 24 to 48 hours.", "page_or_section": "Chapter 7.4 Gravel Wetlands, page 70" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Recommended infiltration should be less than 2.41 inches per hour but great enough that one inch of stored precipitation infiltrates in 24 hours (i.e. >0.04 inches per hour).", "page_or_section": "Chapter 7.7 Manmade Pervious Surfaces, page 84" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Maine Vol III (Augusta pattern).", "fields_not_found": [] }, "source": { "document_url": "https://www.maine.gov/dep/land/stormwater/stormwaterbmps/vol3/volume%20III%20May%202016.pdf", "landing_page_url": "https://www.portlandmaine.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "portland-me.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 2, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:49:22.842Z", "enrich_model": "composer-2.5:run-229c97cd-4c87-48c6-8897-2be2b5fded9c", "enrich_notes": "WQv sizing uses 1.0 inch over impervious area plus 0.4 inch over landscaped/developed vegetated area (Volume III Ch. 7). Underdrained vegetated soil filters require 18 inches minimum separation from seasonal high water table or bedrock; many other BMPs specify 1 foot (12 inches). Filter and gravel-wetland drawdown targets are 24–48 hours; detention basins should be dry within 2–3 days. Wet pond plug-flow shape minimum L:W is 2:1 (3:1 preferred). Pervious surfaces cite infiltration test bounds (<2.41 in/hr and >0.04 in/hr) and 8-inch minimum pretreatment filter layer; proprietary pretreatment uses Maine DEP Appendix B approval letters, not TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "portland-or", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/portland-or/", "data_url": "https://stormwateratlas.com/data/manuals/portland-or.json", "document_metadata": { "jurisdiction_name": "City of Portland", "jurisdiction_level": "municipality", "state_code": "OR", "document_title": "Stormwater Management Manual", "version_or_edition": "December 2020", "adoption_or_effective_date": "2020-12", "last_revised_date": "2020-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Achieve 70% TSS removal from runoff resulting from 90% of the average annual rainfall (1.61 inches over 24 hours, or 0.19 in/hr for a 5-minute time of concentration); the water quality design storm is sized for 90% of the average annual rainfall.", "peak_flow_calculation_method": [ "Rational Method", "Santa Barbara Urban Hydrograph (SBUH) Method", "NRCS TR-55", "HEC-HMS", "HEC-1", "EPA-SWMM", "Continuous Simulation" ], "required_hydrologic_hydraulic_software": [ "Presumptive Approach Calculator (PAC)" ], "approved_bmp_categories": [ "Ecoroof", "Permeable Pavement", "Filter Strip", "Driveway Center Strip", "Green Street", "Rain Garden", "Basin", "Planter", "Surface Sand Filter", "Grassy Swale", "Wet Pond", "Extended Wet Pond", "Dry Pond", "Sump", "Drywell", "Soakage Trench", "Subsurface Sand Filter", "Manufactured Stormwater Treatment Technologies (MSTT)", "Structured Detention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Portland", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Portland", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Portland, Oregon", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "December 2020", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "December 2020", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "December 2020", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The SWMM is a BES Administrative Rule and is authorized by Portland City Code Chapter 17.38.", "page_or_section": "Page 1-5, Section 1.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "70% removal of total suspended solids (TSS) is required from the runoff from 90% of the average annual rainfall (1.61 inches over 24 hours, or 0.19 in/hr for a time of concentration of 5-minutes).", "page_or_section": "Page 1-19, Section 1.3.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "use either the Santa Barbara Urban Hydrograph (SBUH) Method, NRCS's TR-55, the Army Corps of Engineers' Hydrologic Modeling System (HEC-HMS) or HEC-1, or the Environmental Protection Agency's Storm Water Management Model (EPA-SWMM)", "page_or_section": "Page 2-41, Section 2.5.3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The Presumptive Approach can be used by design professionals to size green streets, planters, and basins using the Presumptive Approach Calculator (PAC), an online calculator maintained by BES.", "page_or_section": "Page 2-36, Section 2.5.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Ecoroof ... Permeable Pavement ... Filter Strip ... Green Street ... Rain Garden ... Basin ... Planter ... Drywell ... Soakage Trench ... MSTT ... Structured Detention", "page_or_section": "Page 2-34, Table 2-9" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "70% removal of total suspended solids (TSS) is required from the runoff from 90% of the average annual rainfall (1.61 inches over 24 hours", "page_or_section": "Chapter 1, page 30 (portland-or-c0018)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the drawdown time to the reference point must not exceed 30 hours", "page_or_section": "Chapter 2, page 102 (portland-or-c0078)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum separation distance of 5 ft between the bottom of the facility and the seasonal high groundwater level", "page_or_section": "Chapter 1, page 28 (portland-or-c0017)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding depth: 12 inches", "page_or_section": "Chapter 3 Rain Garden, page 139 (portland-or-c0099)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Amend the soil with 3 inches of compost, blend to a depth of 12 inches below grade.", "page_or_section": "Chapter 3 Rain Garden, page 139 (portland-or-c0099)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "BES requires a minimum design infiltration rate of 2 in/hr unless otherwise approved", "page_or_section": "Chapter 3 Drywells, page 168 (portland-or-c0107)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Wet ponds and extended wet ponds (the top of the permanent pool)... drawdown time to the reference point must not exceed 30 hours", "page_or_section": "Chapter 2, page 102 (portland-or-c0078)" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Grassy swales on private property: Minimum bottom width: 2 ft (must be flat)", "page_or_section": "Chapter 3, page 194 (portland-or-c0118)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://www.portland.gov/sites/default/files/policies/enb-4.01-stormwater-management-manual-december-2020.pdf", "landing_page_url": "https://www.portland.gov/bes/stormwater/2020-stormwater-management-manual", "retrieved_at": "2026-08-07T17:54:24.003Z", "original_filename": "portland-or.pdf" }, "design_parameters": { "wqv_depth_inches": 1.61, "max_drawdown_hours": 30, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 30, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:49:54.279Z", "enrich_model": "composer-2.5:run-80093678-7f1c-4357-a6ce-41a2619ec147", "enrich_notes": "Portland WQ standard is 70% TSS from runoff for 90% of average annual rainfall (1.61 in/24 hr). Level 1 quantity storm is 10-year 24-hr (3.4 in). Infiltration required at tested/design rate ≥2 in/hr unless exceptions. Multiple facility types share 30-hr max drawdown and 5-ft (60 in) SHGW separation. Rain garden sizing factor 0.10 footprint; ponding 12 in. Grassy swale private minimum bottom width 2 ft. MSTTs use BES approved list, not a named third-party verification program in excerpt.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "providence-ri", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/providence-ri/", "data_url": "https://stormwateratlas.com/data/manuals/providence-ri.json", "document_metadata": { "jurisdiction_name": "City of Providence", "jurisdiction_level": "municipality", "state_code": "RI", "document_title": "Rhode Island Stormwater Design and Installation Standards Manual (adopted statewide; applies in Providence)", "version_or_edition": "Amended March 2015", "adoption_or_effective_date": "2015-03-01", "last_revised_date": "2015-03-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Statewide RISDISM eleven minimum standards apply in Providence (LID site planning; groundwater recharge Rev; water quality WQv; channel protection CPv; overbank flood protection Qp; etc.). Structural STPs sized to meet WQv and related standards; construction SESC practices sized for 1 inch of runoff where specified.", "peak_flow_calculation_method": [ "Water Quality Volume (WQv)", "Recharge Volume (Rev)", "Channel Protection Volume (CPv)", "Overbank Flood Protection (Qp)", "Eleven RISDISM minimum standards" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "LID site planning and design strategies", "Groundwater recharge practices", "Structural stormwater treatment practices (Chapter 5)", "Channel protection / flood control practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "RHODE ISLAND DEPARTMENT OF ENVIRONMENTAL MANAGEMENT AND COASTAL RESOURCES MANAGEMENT COUNCIL", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "State of Rhode Island / Providence capital", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Rhode Island", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "RHODE ISLAND STORMWATER DESIGN AND INSTALLATION STANDARDS MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "AMENDED MARCH 2015", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Amended March 2015", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Eleven minimum standards ... State of Rhode Island", "page_or_section": "Chapter 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality, WQv; Channel Protection, CPv; and Overbank Flood Protection, Qp", "page_or_section": "Chapter 3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "for Filter Strip Pretreatment Sizing................................................. 6-5 Table 7-1: Minimum Required Storage Volumes for Basins Used for Enhanced Pollutant Removal .........................................................................................", "page_or_section": "p. 6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Structural Stormwater Treatment Practices for Meeting Water Quality", "page_or_section": "Chapter Five" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "use 1.2 inches for the Water Quality Storm that produces 1 inch of runoff from impervious surfaces", "page_or_section": "Appendix D, pages 271-272" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Compute WQv = (1”)(1.1 ac)/12”/ft", "page_or_section": "Appendix D, page 272" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time of 48 hours.", "page_or_section": "Section 5.3, page 103" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "(2 days is the maximum tf for bioretention)", "page_or_section": "Section 5.5.4, page 132" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Separation from seasonal high groundwater table and bedrock of at least 3 feet except for strictly residential land uses, for which it may be reduced to 2 feet.", "page_or_section": "Section 5.3, page 103" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "A 24” to 48” deep planting soil bed (depending on requirements of proposed vegetation)", "page_or_section": "Section 5.5.4, page 132" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 6” to 9” deep surface ponding area", "page_or_section": "Section 5.5.4, page 132" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Minimum soil infiltration rate of 0.5 inches per hour.", "page_or_section": "Section 5.3, page 103" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours.", "page_or_section": "Section 5.2, pages 87-88" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "For a Shallow WVTS: Minimum flowpath of 2:1 (length to width).", "page_or_section": "Section 5.2, page 88" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall be designed with a bottom width no greater than 8 ft to avoid potential gullying and channel braiding, but no less than 2 ft.", "page_or_section": "Section 5.7.4, page 148" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Open channels shall have a maximum longitudinal slope of 4%, without check dams.", "page_or_section": "Section 5.7.1, page 147" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide RISDISM used for Providence capital coverage; city may have additional local ordinance requirements. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://dem.ri.gov/sites/g/files/xkgbur861/files/pubs/regs/regs/water/swmanual15.pdf", "landing_page_url": "https://dem.ri.gov/environmental-protection-bureau/water-resources/permitting/stormwater-permitting/stormwater-rules", "retrieved_at": "2026-08-10T09:06:14.926Z", "original_filename": "providence-ri.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 9, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:50:52.963Z", "enrich_model": "composer-2.5:run-c32be17a-82e1-47fa-b7aa-13848ea43728", "enrich_notes": "Water quality storm uses 1.2 in rainfall producing 1 in impervious runoff (Appendix D). SHGT separation is 3 ft (36 in) generally, 2 ft (24 in) for strictly residential infiltration/permeable paving; WVTS at LUHPPL cites 3 ft to water table. Bioretention planting soil 24–48 in (12 in case-by-case); ponding zone 6–9 in (examples use 9 in). Dry swale: 30 in soil bed, ≤12 in average ponding. WVTS Shallow L:W 2:1; Gravel WVTS 1:1. Green roof slopes ≤20% extensive / ≤6% intensive; no explicit media depths in excerpts. TAP acronym only; no MTD verification program named for manufactured devices.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "raleigh-nc", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/raleigh-nc/", "data_url": "https://stormwateratlas.com/data/manuals/raleigh-nc.json", "document_metadata": { "jurisdiction_name": "City of Raleigh", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "Stormwater Design Manual", "version_or_edition": "November 2024", "adoption_or_effective_date": "2024-11-02", "last_revised_date": "2024-11", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "WQv and SCM design; references NCDEQ Stormwater Control Measure Design Manual. Nutrient and peak rate controls apply per City stormwater ordinance and this manual.", "peak_flow_calculation_method": [ "Peak rate control for design storms", "SCM / detention design per City manual and NCDEQ SCM Design Manual" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater Control Measures (SCMs)", "Bioretention", "Wet ponds", "Detention", "Other NCDEQ-approved SCMs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Raleigh Stormwater Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Raleigh", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "North Carolina", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "NCDEQ SCM Design Manual", "page_or_section": "References" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "design storms / peak rate", "page_or_section": "Design criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Control Measures", "page_or_section": "SCM chapters" }, { "field": "shwt_separation_inches", "excerpt": "The depth to the SHWT shall be a minimum of 12 inches measured from the lowest ground surface elevation.", "page_or_section": "6.5.9 Level Spreader – Filter Strip (LS-FS), page 6-22" }, { "field": "ed_drain_time_hours", "excerpt": "If not designing for nutrient removal credit, maximum drawdown time is 2 days.", "page_or_section": "6.5.12 Dry Pond, page 6-25" }, { "field": "length_to_width_ratio", "excerpt": "A minimum flow length to width ratio (L:W) shall be 3:1.", "page_or_section": "6.5.4 Stormwater Wetland, page 6-16" }, { "field": "length_to_width_ratio", "excerpt": "If designing for nutrient removal credit, the flow length to pond width ratio (L:W) shall be 3:1.", "page_or_section": "6.5.12 Dry Pond, page 6-25" }, { "field": "swale_bottom_width_inches", "excerpt": "Minimum swale bottom width of 2 feet.", "page_or_section": "6.5.2 Bioretention pretreatment, page 6-12" }, { "field": "swale_longitudinal_slope_percent", "excerpt": "Vegetated Swale: maximum longitudinal slope of 5%, 2% preferred.", "page_or_section": "6.5.2 Bioretention pretreatment, page 6-12" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Raleigh SDM effective Nov 2, 2024; adopts/modifies NCDEQ SCM guidance. Confirm exact return-period list from hydrology chapter. Pipeline excerpt repair removed 5 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method" ] }, "source": { "document_url": "https://cityofraleigh0drupal.blob.core.usgovcloudapi.net/drupal-prod/COR16/Stormwater%20Design%20Manual.pdf", "landing_page_url": "https://raleighnc.gov/stormwater/services/stormwater-permitting-and-inspections-development/stormwater-design-manual", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "raleigh-nc.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:51:25.411Z", "enrich_model": "composer-2.5:run-63c980d4-1b31-44bb-966a-8e3227c9ddc3", "enrich_notes": "Raleigh SDM (Sept 2024) adds city requirements atop NCDEQ SCM MDCs; many numeric limits defer to NCDEQ chapters. Table 5.1 lists compliance design storms (1.34 in runoff volume match, 1 in nitrogen/SNAP) but does not label either as WQv rainfall depth. Wet pond release described as 2–5 days (not a single max drawdown hour). Bioretention pretreatment vegetated swale: max slope 5% (2% preferred), min bottom width 2 ft, check dams min 6 in. Wet pond/wetland permanent pool within 6 in of SHWT or liner per acre thresholds (25 ac wet pond, 10 ac wetland).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "reading-pa", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/reading-pa/", "data_url": "https://stormwateratlas.com/data/manuals/reading-pa.json", "document_metadata": { "jurisdiction_name": "City of Reading", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual / Act 167", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "PA PCSM Manual pollutant-load approach coupling volume and water quality management; Act 167 / MS4 ordinances require BMPs consistent with Pennsylvania Stormwater BMP / PCSM Manual.", "peak_flow_calculation_method": [ "PA PCSM / Stormwater BMP Manual methods", "Act 167 stormwater management ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Volume-reducing SCMs", "Water quality SCMs", "Post-construction BMPs per PA Manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Reading MS4 / Act 167 cites PA PCSM Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DRAFT / Page 1-3 1.1 OVERVIEW OF PCSM MANUAL This PCSM Manual establishes DEP-approved procedures for conducting PCSM stormwater analyses and provides SCM standards that can be used for regulatory compliance under Chapter 102. These procedures and standards may be applied to he", "page_or_section": "p. 12" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Permanent pool volume should hold the runoff generated by 1.2-inch/2-hour rainfall over the contributing drainage area.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Page 3-135 / Section 3.5.4 Infiltration Trench" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / Page B-31" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Table 3-90: 3.6.1 Bioretention — Soil Media Depth Min. 18 in", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Permeable pavement materials with greater than or equal to one foot of storage underneath are considered permeable pavement systems with underground storage", "page_or_section": "Page 3-126 / Section 3.5.3 Permeable Pavement" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Table 3-90: 3.8.2 Naturalized Detention Basin — Maximum Ponding Time 72 hrs", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio should be at least two to one.", "page_or_section": "Page 3-205 / Section 3.6.6 Engineered Stormwater Treatment Wetland" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Table 3-90: 3.6.2 Green Roof — Soil Media Depth Min. 3 in (Typically, lightweight growing material.)", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom widths range from two feet to eight feet.", "page_or_section": "Page 3-96 / Vegetated Conveyance — range only, no single design width" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via PA PCSM Manual (Allentown/Harrisburg pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_parameters.shwt_separation_inches" ] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "reading-pa.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:52:16.257Z", "enrich_model": "composer-2.5:run-590ed04e-ae37-4298-aca0-2d177e41c282", "enrich_notes": "PA PCSM DRAFT (386-0300-001): Table 3-90 consolidates ponding times, media depths, and 2 ft SHWT separation for infiltration SCMs; bioinfiltration vs bioretention distinguished by infiltration rate thresholds (0.25 and 0.4 in/hr). MRC uses 1.2-inch/2-hour storm routing; wet basins sized with 1.2-inch/2-hour permanent pool volume and 5 ft minimum permanent pool depth.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "richmond-va", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/richmond-va/", "data_url": "https://stormwateratlas.com/data/manuals/richmond-va.json", "document_metadata": { "jurisdiction_name": "City of Richmond", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Water Resources Guidance Manual", "version_or_edition": "July 2025", "adoption_or_effective_date": "2025-07", "last_revised_date": "2025-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "City is VSMP/VESMP authority. Stormwater plans must meet Virginia water quality and quantity criteria using the Runoff Reduction Method / spreadsheet, Virginia Stormwater Management Handbook, and City of Richmond Stormwater Management Design and Construction Standards Manual for drainage design. Chesapeake Bay / RPA water quality impact assessment requirements apply where designated.", "peak_flow_calculation_method": [ "COR Stormwater Management Design and Construction Standards Manual (storm drain system)", "Virginia Stormwater Management Handbook quantity criteria", "Runoff Reduction Method", "100-year floodplain / floodway requirements" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Virginia BMP Clearinghouse / Handbook practices", "Detention / retention", "Runoff reduction BMPs", "Erosion and sediment control measures (VESCH)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF RICHMOND, WATER RESOURCES GUIDANCE MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Richmond", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Virginia Department of Environmental Quality (DEQ)", "page_or_section": "Introduction" }, { "field": "document_metadata.document_title", "excerpt": "Water Resources Guidance Manual", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Virginia Stormwater Management Program (VSMP) / Virginia Stormwater Management Handbook", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year flood / storm drain design references", "page_or_section": "Glossary / checklists" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Runoff Reduction Method / Runoff Reduction Spreadsheet", "page_or_section": "Guidance" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Stormwater Management Design and Construction Manual that shall be used to prepare stormwater design", "page_or_section": "Guidance" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "stormwater quantity and water quality / detention/retention", "page_or_section": "Plan requirements" }, { "field": "practice_mentions.swale", "excerpt": "Storm drainage facility: any kind of natural or man-made structure, such as a sewer, ditch, creek, river, lake, swale, or any other facility that stormwater or runoff may flow through", "page_or_section": "Glossary, page 6" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Guidance manual (process + VA criteria). Original Design & Construction Standards PDF was image-only; supplement later if text layer available. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://rva.gov/sites/default/files/2025-07/Richmond%20Water%20Resources%20Guidance%20Manual_Final_6.25.2025.pdf", "landing_page_url": "https://rva.gov/", "retrieved_at": "2026-08-10T08:34:54.567Z", "original_filename": "richmond-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T09:55:35.027Z", "enrich_model": "composer-2.5:run-943a2b2b-ff4c-4929-82ed-a6ac1cf923c0", "enrich_notes": "Excerpts are glossary, permit thresholds, CBPA/RMA/IDA process, and plan review checklists. Stormwater design criteria are delegated to the Virginia Stormwater Management Handbook (VSMH), Runoff Reduction Method/spreadsheet, and City Stormwater Management Design and Construction Standards Manual—not reproduced here. Water quality volume is defined qualitatively only. Highly permeable soils for RMA mapping use ≥6 in/hr permeability in any part of the profile to 72 in (soil classification, not SCM design infiltration rate).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "roanoke-va", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/roanoke-va/", "data_url": "https://stormwateratlas.com/data/manuals/roanoke-va.json", "document_metadata": { "jurisdiction_name": "City of Roanoke", "jurisdiction_level": "municipality", "state_code": "VA", "document_title": "Stormwater Management Design Manual — Chapter 5 Stormwater Hydrology (+ Ch.12 WQ)", "version_or_edition": "Revised July 1, 2014 (manual Oct 1, 2007 base)", "adoption_or_effective_date": "2014-07-01", "last_revised_date": "2014-07-01", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Ch.12: stormwater quality BMPs per DEQ BMP Clearinghouse; runoff reduction method / water quality compliance worksheet per 9VAC25-870-65. Phosphorus removal is primary design target (assumes metals/TSS also controlled). Channel protection and flood protection for SWM facilities per 9VAC25-870-66. Hydrology Ch.5: open-channel minor 10-year (lining 2- or 10-year by size), major 100-year; culverts 10-/25-year; storm drains 10-year; check 100-year where flooding risk.", "peak_flow_calculation_method": [ "Rational Method (with Cf for storms >10-year)", "SCS Method / hydrographs", "VDOT Drainage Manual / VA SWM Handbook references", "Anderson Method (as applicable)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Virginia BMP Clearinghouse practices", "Manufactured BMPs (Clearinghouse-listed only)", "Retention / detention (Ch.10)", "Open channels / culverts / storm drains" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Roanoke Stormwater Management Design Manual", "page_or_section": "Ch.5 / Ch.12 headers" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Open Channels: Minor Channel Capacity 10-year ... Major Channel Capacity 100-year ... Culverts: Principal Arterial Roads 25-year Other Roads 10-year ... Storm Drains: 10-year", "page_or_section": "§5.2.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "runoff reduction method will be utilized. A water quality compliance worksheet ... 9VAC25-870-65", "page_or_section": "Ch.12 §12.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water quality control is required as well and is discussed in Chapter 12.", "page_or_section": "5.2.3 Stormwater Management Facilities, page 2" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "The primary design references are: • VDOT Drainage Manual • VA SWM Handbook • BMP Clearinghouse • BMP Compliance Worksheet", "page_or_section": "5.1 References, page 1" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Channel protection and flood protection shall be addressed in accordance with the criteria set forth in Section 9VAC25-870-66 of the Stormwater Mangement Regulations.", "page_or_section": "5.2.3.1 New Development, page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Manual is chaptered; ingested Ch.5 hydrology PDF plus Ch.12 pollutant-removal criteria from city DocumentCenter. Prefer full combined PDF if published later.", "fields_not_found": [] }, "source": { "document_url": "https://www.roanokeva.gov/DocumentCenter/View/1181/Chapter-5-Stormwater-Hydrology", "landing_page_url": "https://www.roanokeva.gov/1065/Stormwater-Management-Code", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "roanoke-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T09:56:36.386Z", "enrich_model": "composer-2.5:run-58f05a24-60a2-4583-ab64-7a2781a7c88a", "enrich_notes": "Corpus is Chapter 5 hydrology (design storm frequencies, tc/travel time, rational/SCS methods) plus appendices 5B–5C soil/rainfall references. Water quality BMP sizing and practice-specific criteria are deferred to Chapter 12, Virginia BMP Clearinghouse, VA SWM Handbook, and 9VAC25-870-65/66; no explicit WQv depth, drawdown, infiltration design rate, or SCM dimensional parameters appear in supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "rochester-mn", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/rochester-mn/", "data_url": "https://stormwateratlas.com/data/manuals/rochester-mn.json", "document_metadata": { "jurisdiction_name": "City of Rochester", "jurisdiction_level": "municipality", "state_code": "MN", "document_title": "Storm Water Management Plan", "version_or_edition": "October 1997; Revised December 1999", "adoption_or_effective_date": "1999-12-01", "last_revised_date": "1999-12-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Storm sewers: 10-year. Major drainage / ponds: greater of 100-year 24-hour (6.2 in) or 10-day snowmelt; SCS Type II distribution. Subdivision ordinance references this plan. Regional rate-control and water-quality basins recommended; wet detention highlighted for sediment/pollutant removal (Ch.6).", "peak_flow_calculation_method": [ "SCS 24-hour Type II (100-year intensity)", "10-year storm sewer design", "Regional detention / rate-control basin modeling" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Storm sewers / trunk drainage", "Regional detention / rate-control basins", "Water quality / wet detention basins", "Sedimentation basins", "Created or restored wetlands" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Storm Water Management Plan Rochester, Minnesota", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "been combined into one section and revised based on the new Phase II rules. 4. Public Education and Involvement Public education information has been incorporated into the report as part of item 3 above. Educational materials have been submitted to City Staff for review. Sin", "page_or_section": "p. 5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "City of Rochester uses a 10-year frequency storm event for storm sewer design, while the greater of the 100-year, 24-hour frequency rainfall event ... (6.2 inches in 24 hours)", "page_or_section": "§5.2 Design Criteria" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city storm water management plan", "page_or_section": "Preface" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the City has selected the 1-year, 6-hour storm event as the criteria for sizing the water quality (permanent pool) volume for treatment ponds. For the Rochester area, this event is equal to 1.8 inches of rainfall.", "page_or_section": "6.3 Design Criteria for Water Quality, page 91" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration trenches should be designed for a maximum of 6 days holding time.", "page_or_section": "10.4 Infiltration, page 135" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soils within the site should have the capacity to infiltrate 0.25 to 0.3 inches / hour to be effective in operation.", "page_or_section": "10.4 Infiltration, page 117 (corpus page 134)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "recommends a separation distance of 2 to 4 feet between the bottom of the structure and the seasonally high water table.", "page_or_section": "10.4 Infiltration, page 118" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet detention basins are the most effective means of removing sediment and the pollutants associated with it", "page_or_section": "6.3 Design Criteria for Water Quality, page 91" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "These practices include the use of grass swales, infiltration trenches and infiltration ponds.", "page_or_section": "10.4 Infiltration, page 117" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Infiltration ponds and trenches operate much like an on-site waste water treatment system.", "page_or_section": "10.4 Infiltration, page 117" }, { "field": "practice_mentions.swale", "excerpt": "Runoff should be pre-treated by a sedimentation pond or grassed swale before discharging to an infiltration structure.", "page_or_section": "10.4 Infiltration, page 135" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "1999 plan still referenced historically; confirm whether newer design standards superseded sections.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.rochestermn.gov/media/wauldibk/1999-rochester-storm-water-management-plan.pdf", "landing_page_url": "https://www.rochestermn.gov/", "retrieved_at": "2026-08-10T09:54:53.513Z", "original_filename": "rochester-mn.pdf" }, "design_parameters": { "wqv_depth_inches": 1.8, "max_drawdown_hours": 144, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:57:07.370Z", "enrich_model": "composer-2.5:run-c1a41be9-5338-432f-8d26-baad987711d9", "enrich_notes": "Water-quality permanent pool volume is sized to the 1-year, 6-hour storm (1.8 in rainfall); Figure 6-5 gives runoff depth by curve number, not a single runoff depth. Wet detention discussed for sediment/pollutant removal with 24–48+ hour detention context, not a single wetland_detention_hours design value. Infiltration soils must infiltrate 0.25–0.3 in/hr (range, no single design rate). EPA OWTS-style SHWT separation stated as 2–4 ft (range). Infiltration trench maximum holding time 6 days (144 h). No bioretention, permeable pavement, green roof, sand filter, manufactured treatment, or explicit extended-detention drain time in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "rochester-ny", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/rochester-ny/", "data_url": "https://stormwateratlas.com/data/manuals/rochester-ny.json", "document_metadata": { "jurisdiction_name": "City of Rochester", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "New York State Stormwater Management Design Manual (adopted; applies in Rochester)", "version_or_edition": "July 31, 2024", "adoption_or_effective_date": "2024-07-31", "last_revised_date": "2024-07-31", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "USDA NRCS TR20", "HydroCAD", "Pond Pack", "StormCAD", "Hydraflow", "HEC-HMS" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Practices", "Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Rochester adopts NYSDEC Stormwater Management Design Manual for MS4/post-construction design", "page_or_section": "Coverage note / city code practice" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "or other individual hired by the municipality Learn about the resources the local program has at its disposal. If government staff are being trained, develop a maintenance plan that is consistent with their knowledge and understanding. Be aware of equipment and materials o", "page_or_section": "p. 323" }, { "field": "document_metadata.state_code", "excerpt": "New York State Department of Environmental Conservation", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT DESIGN MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "urban stormwater runoff 2. To provide design standards on the most effective stormwater management approaches including: o Incorporation of runoff reduction achieved by infiltration, groundwater recharge, reuse, recycle, evaporation/evapotranspiration through the use of runoff", "page_or_section": "p. 11" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1, 2, 10, 100 year design storms (NYS Design Manual)", "page_or_section": "Design criteria chapters" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "page_or_section": "WQv chapter" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "computer program dt depth of trench TR-55 Technical Release No. 55 Urban Hydrology for Small Watersheds du dwelling units ts thickness of stone reservoir E sediment basin efficiency UIC Underground Injection Control ED extended detention USC Unified Soil Classification EPA En", "page_or_section": "pp. 15–16" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "USDA NRCS TR20, HydroCAD, Pond Pack, StormCAD, Hydraflow, HEC-HMS", "page_or_section": "Software guidance" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Ponds; Stormwater Wetlands; Infiltration Practices; Filtering Practices; Open Channel Practices", "page_or_section": "SMP chapters" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "90th percentile rainfall 1.20 inches (Section 4.2)", "page_or_section": "Chapter 7, Table 7.1 (Section 7.1)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WATER QUALITY VOLUME (WQV) - The volume of stormwater runoff, generated from the 90th percentile rain event", "page_or_section": "Glossary" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide a 2' separation distance to water table.", "page_or_section": "Table 3.5 Watershed/Regional Selection Matrix — Ponds" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min 2 ft separation to seasonal high-water table or bedrock", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Tree trenches and tree pits with more than one tree per pit shall have a 2 ft min. separation to the seasonal high water table and bedrock", "page_or_section": "Section 5.3.3.1 Feasibility" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of filter media shall be 30 inches min and 48 inches max", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of filter media shall be 30 inches min and 48 inches max", "page_or_section": "Fact Sheet: Filtration Bioretention (F-5)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max ponding is 12 inches (WQv) and 18 inches (Extreme Flood)", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum ponding depth shall be 12 inches during the WQv event and 18 inches during the Extreme Flood event", "page_or_section": "Fact Sheet: Rain Garden (RR-6)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "soils with an infiltration rate less than 0.5 in/hr", "page_or_section": "Chapter 3, Step 3 (RRv site limitations)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underlying soils shall have an min. infiltration rate of 0.50 inch/hr", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rain gardens shall have underlying soils with an infiltration rate greater than or equal to 0.50 inch/hr", "page_or_section": "Fact Sheet: Rain Garden (RR-6)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size outlet structure to detain WQv for 24 hrs (12 hrs to trout waters)", "page_or_section": "Fact Sheet: Wet Pond (P-2)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Min. flow path of 1.5:1 (length to relative width) from all inlet points to the outflow points across the pond", "page_or_section": "Fact Sheet: Wet Pond (P-2)" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be a min of 2 ft and a max of 8 ft", "page_or_section": "Fact Sheet: Dry Swale (O-1)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality-level coverage record: Rochester adopts the statewide NYS Stormwater Management Design Manual (July 31, 2024). Criteria mirrored from ny-state extraction; city-specific ordinance overlays not separately extracted. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://extapps.dec.ny.gov/fs/projects/24-25DraftCGPDesignManual/Manual.SW.CGP.2024-07-31.Design_Manual_Issued_2024-07-31.pdf", "landing_page_url": "https://dec.ny.gov/environmental-protection/water/water-quality/stormwater/construction-stormwater-toolbox", "retrieved_at": "2026-08-10T09:15:00.000Z", "original_filename": "rochester-ny.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:57:43.274Z", "enrich_model": "composer-2.5:run-9f1eae18-662d-4d28-83e1-9594025acd3e", "enrich_notes": "WQv uses 90th-percentile rainfall P (example site P = 1.20 in per Table 7.1 / Section 4.2), not a fixed statewide inch depth in every excerpt. Minimum infiltration feasibility threshold fc ≥ 0.50 in/hr is repeated; practices infeasible below 0.5 in/hr site-wide per Step 3. SHWT separation commonly 2 ft (4 ft sole-source aquifer for some practices). Rain gardens (RR-6) specify 12 in min infiltration / 18 in min filtration media—distinct from standard bioretention (F-4/F-5) at 30 in min media.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "rockford-il", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/rockford-il/", "data_url": "https://stormwateratlas.com/data/manuals/rockford-il.json", "document_metadata": { "jurisdiction_name": "City of Rockford", "jurisdiction_level": "municipality", "state_code": "IL", "document_title": "Stormwater Technical Guidance Manual", "version_or_edition": "May 18, 2015", "adoption_or_effective_date": "2015-05-18", "last_revised_date": "2015-05-18", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Peak release rate from a development site shall not exceed 0.2 cfs/acre for the 100-year (0.01 AEP) storm. Minor system typically 10-year; major system 100-year. Design rainfall from Illinois State Water Survey Bulletin 70 Northwest sectional statistics. BMPs required for water quality; Illinois Urban Manual referenced for practice design.", "peak_flow_calculation_method": [ "HEC-HMS / HEC-1 (SCS runoff)", "SWMM", "TR-20", "TR-55 tabular method", "Bulletin 70 critical-duration storms" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-1", "SWMM", "TR-20", "TR-55" ], "approved_bmp_categories": [ "Site runoff storage / detention", "Overland flow paths", "Best Management Practices hierarchy (avoidance → LID → structural)", "Illinois Urban Manual practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF ROCKFORD STORMWATER TECHNICAL GUIDANCE MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "May 18, 2015", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The peak release rate from a development site shall not exceed 0.2 cfs/acre of development for the 0.01 probability in any year", "page_or_section": "T2-03(b)" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minor system criteria (typically 10-year) ... major system criteria (the 100-year) ... Bulletin 70", "page_or_section": "T2-02 / Table 1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "HEC-HMS, HEC-1 with SCS runoff method, SWMM, TR-20, and TR-55 tabular", "page_or_section": "T2-02(e)" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city technical manual (supplements Stormwater Ordinance)", "page_or_section": "Introduction" }, { "field": "design_parameters.practice_mentions.bioretention", "excerpt": "Utilize bio-retention methods and rain gardens to infiltrate stormwater", "page_or_section": "T2-02(j), page 20" }, { "field": "design_parameters.practice_mentions.infiltration_trench", "excerpt": "Utilize stormwater infiltration methods such as porous and permeable pavements and infiltration trenches", "page_or_section": "T2-02(j), page 20" }, { "field": "design_parameters.practice_mentions.permeable_pavement", "excerpt": "porous and permeable pavements and infiltration trenches", "page_or_section": "T2-02(j), page 20" }, { "field": "design_parameters.practice_mentions.swale", "excerpt": "Grass or vegetated swales, channels or flow paths should be left undisturbed", "page_or_section": "T2-02(j), page 19" }, { "field": "enrich_notes.release_rate", "excerpt": "The design runoff rate for a development shall be the lesser of: ... 2. 0.2 cfs/acre of development.", "page_or_section": "T2-02(e), page 17" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "May 2015 edition; quantity-focused release-rate standard with BMP hierarchy.", "fields_not_found": [] }, "source": { "document_url": "https://www.rockfordil.gov/DocumentCenter/View/400", "landing_page_url": "https://www.rockfordil.gov/274/Stormwater-Environmental-Team", "retrieved_at": "2026-08-10T09:45:18.887Z", "original_filename": "rockford-il.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:58:04.492Z", "enrich_model": "composer-2.5:run-0c66429f-2e7a-47de-b206-1bf211fbfb86", "enrich_notes": "Quantity standard is peak release ≤ lesser of existing rate or 0.2 cfs/acre (100-year); minor system 10-year, major 100-year; ISWS Bulletin 70 Northwest for rainfall. BMP design defers to Illinois Urban Manual (June 2013). Sediment basin excerpt specifies ≥10-hour hold and max outflow 0.065 cfs per acre-inch of runoff for construction sediment control—not mapped to SCM drawdown fields.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "rockville-md", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/rockville-md/", "data_url": "https://stormwateratlas.com/data/manuals/rockville-md.json", "document_metadata": { "jurisdiction_name": "City of Rockville", "jurisdiction_level": "municipality", "state_code": "MD", "document_title": "Maryland Stormwater Design Manual (city MS4 / ESD)", "version_or_edition": "Volume One", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "WQv = (P)(Rv)(A)/12 with P = 1.0 in Eastern / 0.9 in Western Rainfall Zone; ESD to the MEP per Maryland Stormwater Design Manual.", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "ESD practices", "Stormwater Ponds / Wetlands", "Infiltration / Filtering / Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Rockville MS4 follows Maryland Stormwater Design Manual", "page_or_section": "Coverage note" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P= rainfall depth in inches and is equal to 1.0\" in the Eastern Rainfall Zone and 0.9\" in the Western Rainfall Zone", "page_or_section": "Table 2.1 / Chapter 2.0, page 39" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "ED 24 hour drawdown of the water quality volume", "page_or_section": "Table 1.3 Symbols, page 36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The water quality requirement can be met by providing a 24 hour drawdown of a portion of the water quality volume (WQv)", "page_or_section": "Chapter 2.4, page 42" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "providing a 24 hour drawdown of a portion of the water quality volume (WQv) in conjunction with a stormwater pond or wetland system", "page_or_section": "Chapter 2.4, page 42" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "filter bed inverts shall be separated at least four feet vertically (two feet on the lower Eastern shore) from the seasonal high water table", "page_or_section": "Chapter 5 micro-bioretention, page 245" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The invert of the stone reservoir shall be separated at least four feet (two feet on the lower Eastern Shore) from the seasonal high water table", "page_or_section": "Chapter 5 enhanced filters, page 261" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention systems (F-6) shall consist of the following treatment components: A 2½ to 4 foot deep planting soil bed", "page_or_section": "Chapter 3.4.5, page 121" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 12\" deep surface ponding area", "page_or_section": "Chapter 3.4.5, page 121" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Flowpaths of 1.5:1 (length relative to width) and irregular shapes are recommended", "page_or_section": "Section 3.1.4 Minimum Pond Geometry, page 92" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Cpv = 24 hour (12 hour in USE III and IV watersheds) extended detention of post-developed one-year, 24 hour storm event", "page_or_section": "Table 2.1, page 39" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Maryland Design Manual (Annapolis/Baltimore pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_parameters.wqv_depth_inches" ] }, "source": { "document_url": "https://mde.maryland.gov/programs/water/StormwaterManagementProgram/Documents/www.mde.state.md.us/assets/document/sedimentstormwater/MD%20SWM%20Volume%201.pdf", "landing_page_url": "https://www.rockvillemd.gov/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "rockville-md.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:58:26.852Z", "enrich_model": "composer-2.5:run-8ceb07da-48f8-4bf5-9997-f96ae95e6915", "enrich_notes": "WQv rainfall P is 1.0 in (Eastern Rainfall Zone) or 0.9 in (Western Rainfall Zone); confirm zone for Rockville. WQv ED is 24 h drawdown of a portion of WQv; Cpv is 24 h (12 h in USE III/IV) extended detention of 1-yr post-dev runoff. Infiltration practices (I-1/I-2) target exfiltration over two days (48 h). F-6 bioretention: 2.5–4 ft planting soil, 12 in surface ponding; filter drain time tf max 2.0 days for bioretention. Micro-bioretention filter beds 24–48 in deep, ponding ≤12 in; rain gardens ponding ≤6 in, 6–12 in planting soil, 2 ft above SHWT. Enhanced filter stone reservoir ≥12 in thick; reservoir invert 4 ft (48 in) from SHWT except 2 ft on lower Eastern Shore. Pond deep pool areas ≥4 ft trigger bench requirements; aquatic bench max 18 in below normal pool.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "round-rock-tx", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/round-rock-tx/", "data_url": "https://stormwateratlas.com/data/manuals/round-rock-tx.json", "document_metadata": { "jurisdiction_name": "City of Round Rock", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Drainage Criteria Manual — Section 8 Stormwater Management", "version_or_edition": "Section 8 (DCM published as separate section PDFs)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25 ], "water_quality_volume_method": "On-site SWM ponds reduce post-development peaks to pre-development for the 2-, 10-, and 25-year storms at each discharge point (small ponds <25 ac drainage; large 25–64 ac; >64 ac treated as regional). Facilities may include detention, retention, extended detention, infiltration, and sedimentation ponds for peak control and water-quality benefits. Full DCM hydrology is in other section PDFs.", "peak_flow_calculation_method": [ "On-site SWM pond peak-rate matching (2/10/25-year)", "Detention pond storage determination (§8.4)", "Regional Stormwater Management Program alternative" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Retention ponds", "Extended detention", "Infiltration ponds", "Sedimentation ponds", "Regional drainage improvements (RSMP)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Drainage Criteria Manual / City of Round Rock", "page_or_section": "Section 8 header" }, { "field": "document_metadata.document_title", "excerpt": "SECTION 8– STORMWATER MANAGEMENT", "page_or_section": "Title" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "On-site SWM ponds shall be designed to reduce post-development peak rates of discharge to existing pre-development peak rates of discharge for the 2, 10, and 25 year storm events", "page_or_section": "§8.3.2" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "--- page 2 --- 8-2 Drainage Criteria Manual SECTION 8 - STORMWATER MANAGEMENT SECTION 8 - STORMWATER MANAGEMENT 8.1.0 GENERAL Stormwater Management (SWM) programs aimed at controlling increased urban runoff generated by development are a top priority in urban", "page_or_section": "p. 2" }, { "field": "practice_mentions.extended_detention", "excerpt": "SWM facilities such as detention, retention, extended detention, infiltration, and sedimentation ponds", "page_or_section": "8.1.0 GENERAL, page 8-2" }, { "field": "practice_mentions.extended_detention", "excerpt": "SWM ponds may be further classified as retention or detention ponds and may incorporate water quality Best Management Practices (BMPs) such as sedimentation, infiltration, or filtration", "page_or_section": "8.3.1 General, page 8-4" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "detention, retention, extended detention, infiltration, and sedimentation ponds", "page_or_section": "8.1.0 GENERAL, page 8-2" }, { "field": "practice_mentions.wet_pond", "excerpt": "SWM ponds may be further classified as retention or detention ponds", "page_or_section": "8.3.1 General, page 8-4" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "reduce post-development peak rates of discharge to existing pre-development peak rates of discharge for the 2, 10, and 25 year storm events", "page_or_section": "8.3.2 Performance Criteria for on-Site SWM Ponds B, page 8-4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Only Section 8 ingested (7 pages); remaining DCM sections (policy, hydrology, storm drains) are separate city PDFs.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.roundrocktexas.gov/wp-content/uploads/2014/12/Drainage-Stormwater-Management-08.pdf", "landing_page_url": "https://www.roundrocktexas.gov/", "retrieved_at": "2026-08-10T09:54:53.508Z", "original_filename": "round-rock-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "wet_pond" ], "enriched_at": "2026-08-13T09:59:00.571Z", "enrich_model": "composer-2.5:run-9ff2edc8-0c89-4793-9749-c545a372e795", "enrich_notes": "Section 8 focuses on on-site and regional SWM ponds for peak control (post-development peaks to pre-development for 2-, 10-, and 25-year storms). Approved facility types include detention, retention, extended detention, infiltration, and sedimentation ponds; RSMP optional in lieu of on-site controls. No explicit WQv depth, drawdown times, or LID/BMP dimensional criteria in ingested pages; hydrology uses City of Austin rainfall distribution (Appendix A) and hydrograph routing. Parking-lot detention limits 100-year ponding to average 8 in., max 12 in. (not mapped to canonical SCM depth fields).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "sacramento-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/sacramento-ca/", "data_url": "https://stormwateratlas.com/data/manuals/sacramento-ca.json", "document_metadata": { "jurisdiction_name": "City of Sacramento", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Onsite Design Manual", "version_or_edition": "Rev. 03/01/2026", "adoption_or_effective_date": null, "last_revised_date": "2026-03-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Stormwater quality post-construction requirements and LID design per Section 7. Detention volume for increased imperviousness sized using City basin-specific 100-year storage required per acre (Figure 10); 10-year storage must remain outside vehicular/pedestrian surfaces when part of 100-year volume is stored on pavement.", "peak_flow_calculation_method": [ "Rational Method (static analysis)", "Dynamic analysis option for drainage studies", "Mitigate increased imperviousness with 100-year storage volume; check 10-year storage when using surface storage" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention", "Retention", "Low Impact Development (LID) design features", "Surface stormwater quality features" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "for properties within the City of Sacramento, this on-site design manual provides the Department of Utilities (DOU) minimum design standards", "page_or_section": "Purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Sacramento", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "state issued WDID number", "page_or_section": "Plan requirements" }, { "field": "document_metadata.document_title", "excerpt": "Onsite Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Rev. 03/01/2026", "page_or_section": "Running footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "Rev. 03/01/2026", "page_or_section": "Running footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Stormwater quality treatment and Low Impact Development (LID) methods", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10 and 100-year event tailwater elevations and sources.", "page_or_section": "Drainage study requirements" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Multiply the additional impervious area by the 100-year event storage required per acre", "page_or_section": "Detention sizing procedure" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "shall use the rational method as specified below; only a 10-year event", "page_or_section": "Section 3.1.2 Rational Method" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention & Retention / Low Impact Development (LID) Design", "page_or_section": "TOC Sections 3.10 / 7.2" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the soil is shown to allow a maximum draw down time of 48 hours", "page_or_section": "Section 3.10 Detention & Retention, page 17" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention planters", "page_or_section": "Section 7.2 Low Impact Development (LID) Design, page 33" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roofs", "page_or_section": "Section 7.2 Low Impact Development (LID) Design, page 33" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous Pavement/Pervious surfaces", "page_or_section": "Section 7.2 Low Impact Development (LID) Design, page 33" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Green roofs, pervious pavement, gravel, pavers with pervious base and joints shall be considered entirely pervious", "page_or_section": "Section 3.1.1 Onsite Project Storage Method, page 8" }, { "field": "practice_mentions.extended_detention", "excerpt": "For projects that include onsite dry detention areas", "page_or_section": "Section 3.1.3 Onsite Computer Model, page 9" }, { "field": "practice_mentions.wet_pond", "excerpt": "For onsite detention areas that include a permanent pool, the starting HGL for each pipe segment connected to the pool, is the permanent pool water surface elevation", "page_or_section": "Section 3.1.3 Onsite Computer Model, page 9" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Sacramento Onsite Design Manual covers drainage plus SWQ/LID; numeric SWQDV formulas may live in referenced regional manuals. Adoption date not explicit beyond revision stamp.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.cityofsacramento.gov/content/dam/portal/dou/utilities/development-standards/OnsiteDesignManual.pdf", "landing_page_url": "https://www.cityofsacramento.gov/utilities", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "sacramento-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "permeable_pavement", "wet_pond" ], "enriched_at": "2026-08-13T09:59:34.873Z", "enrich_model": "composer-2.5:run-7659777f-debf-4c8b-aecd-b6767d37feab", "enrich_notes": "Stormwater quality sizing and LID detail are delegated to the SQDM (Appendix D worksheet, Chapter 5); this manual sets retention-pond drawdown (48 h), gravel porosity (40%), detention/retention and LID trigger thresholds, and treats green roofs and pervious pavement as fully pervious for impervious-area accounting.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "saint-paul-mn", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/saint-paul-mn/", "data_url": "https://stormwateratlas.com/data/manuals/saint-paul-mn.json", "document_metadata": { "jurisdiction_name": "City of Saint Paul", "jurisdiction_level": "municipality", "state_code": "MN", "document_title": "Stormwater Management Design Standards", "version_or_edition": "January 2026", "adoption_or_effective_date": "2026-01", "last_revised_date": "2026-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Volume control and water quality requirements for sites discharging to the City MS4. Water Quality Volume for construction activity: 1.1 inches of runoff from new impervious surfaces (definition). Prefers green infrastructure / LID; BMP design standards in Section 7 and Minnesota Stormwater Manual.", "peak_flow_calculation_method": [ "Volume control and water quality thresholds (Section 3.1.1)", "Rate control aligned with water quality standards", "References Minnesota Stormwater Manual for BMP design details" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure / LID practices", "Underground retention and infiltration/filtration systems", "Filtration BMPs", "Minnesota Stormwater Manual BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of St. Paul / City of Saint Paul", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Saint Paul", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "Minnesota Stormwater Manual", "page_or_section": "References" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Design Standards", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Minnesota Stormwater Manual", "page_or_section": "Purpose / references" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume means for Construction Activity, one and one-tenth (1.1) inches of runoff", "page_or_section": "Definitions" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Volume Control and Water Quality Threshold", "page_or_section": "Section 3.1.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Underground Retention and Infiltration/Filtration Systems", "page_or_section": "Section 7.8" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume means for Construction Activity, one and one-tenth (1.1) inches of runoff from the sum of the new and Fully Reconstructed Impervious Surfaces", "page_or_section": "SECTION 2 Definitions, page 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume (ft3) = New and Fully Reconstructed Impervious Surfaces (ft2) x 1.1(in) x 1/12 (ft/in)", "page_or_section": "SECTION 5.3 Volume Control, page 15" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Applicants must design the infiltration system to discharge all Stormwater ... through the uppermost soil surface or engineered media surface within 48 hours.", "page_or_section": "SECTION 7.6 Infiltration Practices, page 31" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Applicants must design the filtration system to discharge all Stormwater ... through the uppermost soil surface or engineered media surface within 48 hours.", "page_or_section": "SECTION 7.7 Filtration Practices, page 32" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "With less than three (3) feet of separation distance from the bottom of the infiltration system to the elevation of the seasonally saturated soils or the top of bedrock.", "page_or_section": "SECTION 5.3.3 Volume Control, page 16" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Applicants must employ appropriate onsite testing to ensure a minimum of three (3) feet of separation between the seasonally saturated soils (or from bedrock) and the bottom of the proposed filtration system.", "page_or_section": "SECTION 7.7 Filtration Practices, page 32" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool: 3-10', Minimum average: 4'", "page_or_section": "APPENDIX C Stormwater Management Plan Checklist, Ponds, page 49" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "St. Paul SWMDS Jan 2026; WQv 1.1 in defined; rate-control details in rate sections. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.stpaul.gov/sites/default/files/public-works/st-paul-stormwater-management-design-standards-swmdsjanuary-2026.pdf", "landing_page_url": "https://www.stpaul.gov/departments/public-works/sewer-utility-division/site-plan-review", "retrieved_at": "2026-08-10T08:08:51.648Z", "original_filename": "saint-paul-mn.pdf" }, "design_parameters": { "wqv_depth_inches": 1.1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:00:06.547Z", "enrich_model": "composer-2.5:run-d1a5c0a0-8f61-4d55-8d76-56cb62074af1", "enrich_notes": "WQv is 1.1 in on new and fully reconstructed impervious area. Infiltration and filtration must draw down through the uppermost surface within 48 h. Minimum 3 ft (36 in) separation to seasonally saturated soils or bedrock for infiltration and filtration; pervious pavement is not an acceptable infiltration/WQ BMP. Pond checklist cites permanent pool depth 3–10 ft with minimum average 4 ft (48 in). Field infiltration rates are halved for design; native rates above 8.3 in/hr trigger restrictions—not a mandated design rate. Detailed BMP sizing defers to Minnesota Stormwater Manual Section 7.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "salem-or", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/salem-or/", "data_url": "https://stormwateratlas.com/data/manuals/salem-or.json", "document_metadata": { "jurisdiction_name": "City of Salem", "jurisdiction_level": "municipality", "state_code": "OR", "document_title": "Public Works Design Standards — Administrative Rule 109 (Div. 004 Stormwater)", "version_or_edition": "March 2025", "adoption_or_effective_date": null, "last_revised_date": "2025-03-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Green Stormwater Infrastructure (GSI) to the Maximum Extent Feasible (MEF) per SRC 71.100; water quality design storm represents 80% of average annual runoff volume (NSRR — Numeric Stormwater Retention Requirement). Flow control per SRC 71.095(c). Infiltration facilities sized with design infiltration rate = measured rate / 2 safety factor.", "peak_flow_calculation_method": [ "Flow control performance standards (SRC 71.095)", "Hydrologic analysis Appendix 4D", "100-year floodway / open channel easement criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green stormwater infrastructure (planters, infiltration)", "Infiltration facilities / drywells (UIC)", "Filtration facilities", "Flow control facilities", "Pervious pavement / eco-roofs (impervious area reduction)", "Manufactured stormwater facilities (accepted list)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF SALEM DEPARTMENT OF PUBLIC WORKS ADMINISTRATIVE RULES", "page_or_section": "Header" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Salem", "page_or_section": "Header" }, { "field": "document_metadata.document_title", "excerpt": "004 STORMWATER SYSTEM", "page_or_section": "TOC" }, { "field": "document_metadata.version_or_edition", "excerpt": "Public Works Design Standards - March 2025", "page_or_section": "Landing / filename" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Salem Revised Code / Public Works Design Standards", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Design Storm Event - a design storm event representative of 80 percent of the", "page_or_section": "Definitions" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "flow control performance standards of SRC 71.095(c)", "page_or_section": "Definitions" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Green Stormwater Infrastructure - GSI; Infiltration Facility", "page_or_section": "Definitions" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year floodway", "page_or_section": "Easements" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All stormwater managed by the rain garden must drain from the storage reservoir (bottom of drain rock) within 48 hours after a design storm event ends.", "page_or_section": "Section 4.6(b)(2)-Rain Garden, page 112" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Infiltration or partial infiltration facilities are prohibited on sites with less than 3 ft of vertical separation between the bottom of the facility (i.e., bottom of drain rock layer) and seasonal high ground water elevation.", "page_or_section": "Table 4-1, page 93" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If on-site infiltration testing demonstrates the design infiltration rate of the soil is 0.5 inch/hour or greater, the stormwater facility (GSI) shall be designed as an infiltration facility", "page_or_section": "Section 4.4(a), page 95" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "For stormwater treatment, the wet portion or permanent pool of the wetland shall have a residence time of at least 36 hours, calculated as the treatment design storm volume divided by the average facility outflow rate.", "page_or_section": "Section 4.6(b)(7) Treatment Wetlands, page 124" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The design infiltration rate must be 0.5 inches per hour or greater.", "page_or_section": "Section 4.6(d)(2) Private System, page 109" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The minimum drawdown time for a soakage trench, leach line, or manufactured chamber technology for the applicable design storm event is 48 hours.", "page_or_section": "Section 4.6(b)(4) Subsurface Infiltration, page 119" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Full Admin Rule 109 PDF (multiple divisions). Stormwater criteria concentrated in Div. 004 / SRC 71 references. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.cityofsalem.net/home/showpublisheddocument/420/639198930718730000", "landing_page_url": "https://www.cityofsalem.net/business/building-in-salem/helpful-resources/engineering-and-technical-resources/standard-plans-construction-specifications-and-public-works-design-standards", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "salem-or.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": 36, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:00:39.588Z", "enrich_model": "composer-2.5:run-4ee8a37b-532e-4440-91c8-54602e9f157d", "enrich_notes": "Water quality sizing uses the water quality design storm (Atlas: NSRR ≈ 80% of average annual runoff volume); no WQv depth in inches in excerpts. Native-soil design infiltration rate = measured rate ÷ 2 (factor of safety 2.0); partial/ lined rain gardens use growing media design rate of 3 in/hr. Infiltration infeasible if SHWT separation < 3 ft (Table 4-1); subsurface infiltration prohibited if SHWT within 5 ft of facility bottom. Simplified soakage trench depth 30 in; drywell max drawdown 12 hr when full. Green roofs: 50% of green roof area may be subtracted from impervious area for flow control.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "san-antonio-tx", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/san-antonio-tx/", "data_url": "https://stormwateratlas.com/data/manuals/san-antonio-tx.json", "document_metadata": { "jurisdiction_name": "City of San Antonio", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "Storm Water Design Criteria Manual", "version_or_edition": "April 2019", "adoption_or_effective_date": "2019-04", "last_revised_date": "2019-04", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method (Q = CIA) for drainage areas less than 200 acres", "Modified Rational Method for detention ponds with drainage areas of 20 acres or less", "Unit hydrograph method (preferably SCS Dimensionless Unit Hydrograph in HEC-HMS) for drainage areas 200 acres or greater and for detention ponds greater than 20 acres", "Snyder Unit Hydrograph", "Clark Unit Hydrograph", "NOAA Atlas 14 Volume 11 rainfall intensities / depths for San Antonio and ETJ" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS (preferred for SCS Dimensionless Unit Hydrograph / unit hydrograph modeling)" ], "approved_bmp_categories": [ "Onsite detention facilities (Regional Storm Water Management Program option)", "Fee in-lieu-of (FILO) detention participation", "Low Impact Development (LID) planning referenced in manual TOC" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of San Antonio Texas Unified Development Code", "page_or_section": "Chapter 3 / Local Codes" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The purpose of this Storm Water Design Criteria Manual (SWDCM) is to provide the design engineer with the criteria necessary to design drainage facilities in and around the San Antonio area.", "page_or_section": "Chapter 1 Preface" }, { "field": "document_metadata.state_code", "excerpt": "Texas Water Code – Section 11.086", "page_or_section": "Chapter 3 State Statutes" }, { "field": "document_metadata.document_title", "excerpt": "Storm Water Design Criteria Manual", "page_or_section": "Title / Header" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised April 2019 / Storm Water Design Criteria Manual — April 2019", "page_or_section": "Cover / running header" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised April 2019", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The purpose of this Storm Water Design Criteria Manual (SWDCM) is to provide the design engineer with the criteria necessary to design drainage facilities in and around the San Antonio area.", "page_or_section": "Chapter 1 Preface" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Atlas 14 Rainfall Intensity (inches/hour) by Storm Frequency — 2-YEAR 5-YEAR 10-YEAR 25-YEAR 50-YEAR 100-YEAR 500-YEAR", "page_or_section": "Chapter 5 / Atlas 14 tables" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-year 2-year 5-year 10-year 25-year 50-year 100-year 500-year — Atlas 14, Volume 11 Adjusted Rainfall Values", "page_or_section": "Chapter 5 / Atlas 14 depth tables" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For drainage areas less than 200 hundred (200) acres, the basis for computing runoff shall be the rational formula (as defined in Section 5.3) or some other method provided it is acceptable to the Director of TCI.", "page_or_section": "Section 5.2.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For drainage areas 200 hundred (200) acres or greater, the basis for computing runoff shall be a unit hydrograph method (as defined in Section 5.6), preferably the Soil Conservation Service (SCS) Dimensionless Unit Hydrograph method as contained in the U.S. Army Corps of Engineers Hydrologic Engineering Center HEC-HMS \"Hydrologic Modeling Systems\".", "page_or_section": "Section 5.2.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For detention ponds with drainage areas of twenty (20) acres or less, the basis for computing runoff shall be the modified rational method.", "page_or_section": "Section 5.2.3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rainfall data in this section is based on NOAA Atlas 14, Volume 11 (A14) precipitation", "page_or_section": "Chapter 5 Hydrology" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "preferably the Soil Conservation Service (SCS) Dimensionless Unit Hydrograph method as contained in the U.S. Army Corps of Engineers Hydrologic Engineering Center HEC-HMS \"Hydrologic Modeling Systems\".", "page_or_section": "Section 5.2.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Program by paying a fee- in-lieu-of onsite detention.", "page_or_section": "Front matter / RSWMP policy excerpt" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "principles and practices for the planning, design, construction, maintenance, and management of drainage facilities. It is not the intent of this SWDCM to limit the design capabilities or engineering judgment of the design engineer. Should an error be found within the manu", "page_or_section": "p. 24" }, { "field": "practice_mentions", "excerpt": "13.3 Detention Basins ... 13.4 Retention Basins", "page_or_section": "Chapter 13 STORAGE FACILITIES (TOC)" }, { "field": "enrich_notes", "excerpt": "Provide required storage for the 5, 25, and 100 yr (proposed, ultimate)", "page_or_section": "Appendix A checklist" }, { "field": "enrich_notes", "excerpt": "LID Low Impact Development", "page_or_section": "Chapter 1.2 Acronyms" }, { "field": "enrich_notes", "excerpt": "FILO Fee in Lieu of Detention", "page_or_section": "Chapter 1.2 Acronyms" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Ingested PDF (UDC-Amendment-Drainage-Manual.pdf) extracts primarily through Chapter 5 Hydrology (~52 pages). TOC references later chapters (detention, software, LID) that are not present in this file; water_quality_volume_method and a fuller BMP palette may live in those missing chapters or companion Atlas 14 amendments. Prefer full SWDCM PDF if republished. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.sanantonio.gov/Portals/0/Files/CIMS/Services/UDC-Amendment-Drainage-Manual.pdf", "landing_page_url": "https://www.sa.gov/Directory/Departments/PWD/Storm-Water/Plan-Review", "retrieved_at": "2026-08-10T07:45:00.000Z", "original_filename": "san-antonio-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T10:01:34.196Z", "enrich_model": "composer-2.5:run-244b2094-9da4-4fab-8a48-ebb3df48a6a8", "enrich_notes": "Ingested excerpts are largely TOC, appendices, and Hydrology Ch.5 intro; Ch.13 lists detention and retention basins but no numeric SCM design criteria. Atlas notes WQv method and LID/BMP detail may be in missing chapters. FILO and LID appear as acronyms only (Ch.1). Checklist references 5-, 25-, and 100-year storage requirements without WQv depth or drawdown times.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "san-diego-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/san-diego-ca/", "data_url": "https://stormwateratlas.com/data/manuals/san-diego-ca.json", "document_metadata": { "jurisdiction_name": "City of San Diego", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Stormwater Standards", "version_or_edition": "August 2024 Edition", "adoption_or_effective_date": "2024-08-15", "last_revised_date": "2024-08", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Design Capture Volume (DCV): retain onsite pollutants in runoff from the 24-hour, 85th percentile storm event (Figure B.1-1 or approved site-specific analysis). If full retention is not technically feasible, biofiltration for remaining volume (treat 1.5× DCV not retained, or flow-thru biofiltration holding ≥0.75× DCV not retained); otherwise flow-thru treatment (0.2 in/hr or 85th percentile hourly intensity × 2) plus alternative compliance.", "peak_flow_calculation_method": [ "Continuous simulation hydrologic modeling", "Approved Q2/Q10 regression equations", "Rational method (runoff to BMPs)" ], "required_hydrologic_hydraulic_software": [ "San Diego Hydrology Model (SDHM)", "EPA SWMM" ], "approved_bmp_categories": [ "Harvest and Use (HU-1: Cistern)", "Infiltration (INF-1: Infiltration basin)", "Bioretention (INF-2)", "Permeable pavement (INF-3)", "Dry Wells (INF-4)", "Biofiltration with Partial Retention (PR-1)", "Biofiltration (BF-1)", "Nutrient Sensitive Media Design (BF-2)", "Proprietary Biofiltration (BF-3)", "Vegetated swales (FT-1)", "Media filters (FT-2)", "Sand filters (FT-3)", "Dry extended detention basins (FT-4)", "Proprietary flow-thru treatment control (FT-5)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "THE CITY OF SAN DIEGO Stormwater Standards", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The City of San Diego (City) is required to adopt jurisdiction specific local BMP Design Manual", "page_or_section": "Introduction / Purpose" }, { "field": "document_metadata.state_code", "excerpt": "California Regional Water Quality Control Board for the San Diego Region (SDRWQCB)", "page_or_section": "Purpose of the Storm Water Standards" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Standards", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "The City of San Diego | Stormwater Standards | August 2024 Edition", "page_or_section": "Header / Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective date: August 15, 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "August 2024 Edition", "page_or_section": "Title Page / Headers" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Part 1 of the Stormwater Standards is the adaption of the Model BMP Design Manual to the specific... Standards is designated as the City of San Diego BMP Design Manual", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For flow rates ranging from 10 percent, 30 percent or 50 percent of the pre-development 2-year runoff event (0.1Q2, 0.3Q2, or 0.5Q2) to the pre-development 10-year runoff event (Q10), the post-project discharge rates and durations must not exceed the pre-development rates and durations by more than 10 percent", "page_or_section": "Section 6.3, Page 6-4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "but below the 100-year water surface elevation, additional analysis is", "page_or_section": "Section 1.6 / Hydromodification exemptions" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Each PDP shall implement BMPs that are designed to retain (i.e. intercept, store, infiltrate, evaporate, and evapotranspire) onsite the pollutants contained in the volume of stormwater runoff produced from a 24-hour, 85th percentile storm event (Design Capture Volume (DCV))", "page_or_section": "Section 2.2.1, Page 2-5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Biofiltration BMPs must be designed... and must be sized to: [a] Treat 1.5 times the DCV not reliably retained onsite, OR [b] Treat the DCV not reliably retained onsite with a flow-thru design that has a total volume... sized to hold at least 0.75 times the portion of the DCV not reliably retained onsite", "page_or_section": "Section 2.2.1(a)(i), Page 2-5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Q2 and Q10 refer to flow rates determined based on either continuous simulation hydrologic modeling or the following approved regression equations", "page_or_section": "Section 6.3, Page 6-4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "used in the rational method) should be used to estimate the runoff draining to the BMP", "page_or_section": "Chapter 5 / DMA sizing guidance" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "through reporting of output from the San Diego Hydrology Model, or through other continuous simulation modeling meeting the criteria in Appendix G, as acceptable to the City Engineer", "page_or_section": "Appendix B.4, Page B-28" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Three sets of continuous simulation runs were executed in the EPA SWMM using the default", "page_or_section": "Appendix (SWMM continuous simulation)" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Harvest and Use (HU) HU-1: Cistern; Retention Infiltration (INF) INF-1: Infiltration basin INF-2: Bioretention INF-3: Permeable pavement INF-4: Dry Wells; Partial Retention (PR) PR-1: Biofiltration with partial retention; Biofiltration (BF) BF-1: Biofiltration BF-2: Nutrient Sensitive Media Design BF-3: Proprietary Biofiltration; Flow-thru treatment control (FT) FT-1: Vegetated swales FT-2: Media filters FT-3: Sand filters FT-4: Dry extended detention basins FT-5: Proprietary flow-thru treatment control", "page_or_section": "Section 5.5 / Table, Page 5-13" }, { "field": "fields_not_found", "excerpt": "runoff produced from a 24-hour, 85th percentile storm event (Design Capture Volume (DCV)). The 24-hour, 85th percentile storm event shall be based on Figure B.1-1 in Appendix B", "page_or_section": "p56" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth to seasonally high groundwater tables (normal high depth during the wet season) beneath the base of any infiltration BMP must be greater than 10 feet for full infiltration BMPs to be allowed.", "page_or_section": "Appendix C.2.2.2, page C-9" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Basin length to width ratio is ≥ 2:1 (L:W).", "page_or_section": "Appendix E FT-4 Dry Extended Detention, page E-112" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "An active General Use Level Designation for Basic Treatment, Phosphorus Treatment or Enhanced Treatment under the Washington State Technology Acceptance Protocol-Ecology program is the preferred method of demonstrating that the performance standard is met.", "page_or_section": "Appendix B Table B.6-4 / Selecting Proprietary BMPs, page B-91" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "maximum 36-hour drawdown time for the aggregate storage layer, with surface ponding no greater than a maximum 24-hour drawdown", "page_or_section": "Appendix E INF-2 Bioretention, page E-59 (multiple SCM-specific limits; no single site-wide value extracted)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Surface ponding drawdown time is between 24 and 96 hours.", "page_or_section": "Appendix E FT-4, page E-112 (range only)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Local queue text is truncated relative to full ~786-page PDF; core pollutant-control DCV (85th percentile), hydromodification 0.1–0.5Q2 to Q10, and BMP category table are well supported. Appendix G software section body is incomplete in the local text—SDHM and EPA SWMM appear in sizing/appendix excerpts. 100-year appears mainly in floodplain/exemption context, not as pollutant-control design storm.", "fields_not_found": [] }, "source": { "document_url": "https://www.sandiego.gov/sites/default/files/2024-08/sws_manual_august_2024_update.pdf", "landing_page_url": "https://www.sandiego.gov/stormwater", "retrieved_at": "2026-08-08T10:35:15.140Z", "original_filename": "san-diego-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "Washington State Technology Acceptance Protocol-Ecology (TAPE)", "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:02:45.922Z", "enrich_model": "composer-2.5:run-a20bbd3c-b0e0-4656-bf94-4376e439bcac", "enrich_notes": "DCV sizing uses site-specific 85th-percentile 24-hour depth (Appendix B examples use 0.5–0.6 in, not a fixed WQV depth). Bioretention INF-2 cites max 36 h aggregate and 24 h surface ponding drawdown; permeable pavement INF-3 cites max 36 h drawdown (optional up to 96 h with capture adjustment). Full infiltration requires >10 ft to seasonal high groundwater (120 in). Proprietary BMPs prefer TAPE General Use Level Designation; Pilot/Conditional not acceptable.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "san-francisco-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/san-francisco-ca/", "data_url": "https://stormwateratlas.com/data/manuals/san-francisco-ca.json", "document_metadata": { "jurisdiction_name": "City of San Francisco", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "San Francisco Stormwater Management Requirements and Design Guidelines", "version_or_edition": "May 2016", "adoption_or_effective_date": "2016-05-27", "last_revised_date": "2016-05", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2 ], "water_quality_volume_method": "Combined sewer (Case 1, ≤50% existing impervious): maintain runoff rate and volume at or below pre-development for the 1- and 2-year, 24-hour storms. Combined sewer (Case 2, >50% impervious): reduce runoff rate and volume by 25% relative to pre-development for the 2-year, 24-hour storm (Modified Compliance may trade volume vs peak reductions). Separate sewer Large Projects (≥5,000 sf): SFPUC jurisdiction manage the 90th percentile 24-hour storm; Port jurisdiction manage the 85th percentile 24-hour storm. Separate sewer Small Projects (2,500–5,000 sf): implement at least one Site Design Measure and report runoff reduction via State Water Board SMARTS calculator.", "peak_flow_calculation_method": [ "SFPUC electronic BMP Sizing Calculators (sites ≤5 acres or sub-watersheds ≤2 acres)", "Santa Barbara Urban Hydrograph Method (basis of Combined Sewer Area BMP Sizing Calculator)", "Hydrologic modeling required for larger/more complex projects" ], "required_hydrologic_hydraulic_software": [ "SFPUC BMP Sizing Calculators (combined and separate sewer spreadsheets)", "State Water Board SMARTS calculator (separate sewer Small Projects)" ], "approved_bmp_categories": [ "Rainwater harvesting", "Permeable pavement", "Vegetated roof", "Unlined bioretention / rain garden", "Bioretention swales", "Subsurface infiltration system / infiltration trench", "Infiltration basin", "Constructed wetland", "Lined bioretention / flow-through planter", "Detention tank", "Detention pond", "Wet pond", "High-rate filtration (tree-box filters, media filters; separate sewer Large Projects, approval required)", "Pretreatment: conveyance swales, vegetated buffer strips, swirl separators, drain inserts, water quality inlets (treatment train only)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of San Francisco / San Francisco Public Utilities Commission / Port of San Francisco", "page_or_section": "Acknowledgements / Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Approximately 90 percent of San Francisco is served by a combined sewer system, with the remaining 10 percent served by separate storm sewer systems", "page_or_section": "Chapter 3 / San Francisco's Stormwater Infrastructure" }, { "field": "document_metadata.state_code", "excerpt": "staff from the counties of Contra Costa and Santa Clara, California", "page_or_section": "Acknowledgements" }, { "field": "document_metadata.document_title", "excerpt": "stormwater management requirements and design guidelines", "page_or_section": "Title pages" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "The 2016 SMR performance requirements apply to projects with Preliminary SCPs submitted on or after May 27, 2016.", "page_or_section": "Chapter 5 / Applicability Dates" }, { "field": "document_metadata.last_revised_date", "excerpt": "of impervious surface. ʶ The 2016 version includes an option for eligible projects to comply with Modified Compliance requirements. This option was not available in the 2010 SMR. 6 Separate Sewer Area Performance Requirements Describes performance requirements specific to p", "page_or_section": "p. 17" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This document is an update of the 2010 San Francisco Stormwater Design Guidelines (Guidelines).", "page_or_section": "Executive Summary / Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Case 1: Projects with existing imperviousness of less than or equal to 50 percent must maintain a stormwater runoff rate and volume at or below pre-development conditions for the 1- and 2-year, 24-hour design storms.", "page_or_section": "Chapter 5 / Combined Sewer Area Performance Requirements" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Case 2: Projects with existing imperviousness of greater than 50 percent must reduce the stormwater runoff rate and volume by 25 percent relative to pre-development conditions for the 2-year, 24-hour design storm.", "page_or_section": "Chapter 5 / Combined Sewer Area Performance Requirements" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Projects within SFPUC jurisdiction must manage the 90th percentile, 24-hour storm / Projects within the Port's jurisdiction must manage the 85th percentile, 24-hour storm", "page_or_section": "Chapter 6 / Table 3 Separate Sewer Area Performance Requirements" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "must reduce the stormwater runoff rate and volume by 25 percent relative to pre-development conditions for the 2-year, 24-hour design storm.", "page_or_section": "Chapter 5 Case 2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Projects that are five acres or less, or with sub-watershed areas that are two acres or less, can use the SFPUC's electronic BMP Sizing Calculators to size BMPs. Larger, more complex development projects can use the BMP Sizing Calculators as planning tools, but must use modelling to prove compliance with the SMR.", "page_or_section": "Chapter 4 Task 3B" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Combined Sewer Area BMP Sizing Calculator Approach Using the Santa Barbara Urban Hydrograph Method", "page_or_section": "Chapter 4 Task 3B" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The two calculator spreadsheets, one for combined sewer area projects and one for separate sewer area projects, are available on the SFPUC website at www.sfwater.org/smr.", "page_or_section": "Chapter 4 Task 3B" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Submit estimated runoff reduction volume using the State Water Board SMARTS calculator", "page_or_section": "Chapter 6 Table 3 Small Project" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The required BMP Hierarchy prioritizes infiltration-based BMPs, rainwater harvesting, and vegetated roofs followed by lined bioretention (commonly known as a \"flow-through planter\").", "page_or_section": "Executive Summary / What's New" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "1st Priority: Reduce Stormwater Runoff — Rainwater harvesting, Permeable pavement, Vegetated roof; 2nd Priority: Detain & Biotreat — Unlined bioretention, Subsurface infiltration, Bioretention swales, Infiltration basin, Constructed wetland, Lined bioretention; 3rd Priority: Detain — Detention tank, Wet pond, Detention pond", "page_or_section": "Chapter 5 Figure 7 Combined Sewer Area BMP Hierarchy" }, { "field": "fields_not_found", "excerpt": "percentile, 24-hour storm. This storm translates to a rainfall depth of approximately 0.63", "page_or_section": "p88" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Appendix A: BMP Fact Sheets is another valuable design tool that provides guidance on BMP design parameters, such as the ponding depth, media depth, and maximum drawdown times.", "page_or_section": "Chapter 4, Task 3C Design BMPs (pages 68-69)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "provides guidance on BMP design parameters, such as the ponding depth, media depth, and maximum drawdown times.", "page_or_section": "Chapter 4, Task 3C Design BMPs (pages 68-69)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Projects within SFPUC jurisdiction must manage the 90th percentile, 24-hour storm • Projects within the Port's jurisdiction must manage the 85th percentile, 24-hour storm", "page_or_section": "Table 3, Separate Sewer Area Performance (page 85)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Limitations of infiltration-based BMPs, including set-back distances and depth to groundwater, were updated, and references to the new Appendix C: Criteria for Infiltration-Based BMPs were added.", "page_or_section": "Appendix A Changes (page 19)" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "projects may be able to incorporate high-rate filtration BMPs (e.g. tree-box filters and media filters) into their site design pending approval by the SFPUC or Port.", "page_or_section": "Chapter 6 Separate Sewer Area (pages 91-92)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "SFPUC/Port May 2016 SMR. Design storms emphasized for combined-sewer quantity control are 1- and 2-year 24-hour; separate-sewer Large Projects use 85th/90th percentile 24-hour storms rather than return-period WQv. Numeric percentile depths live in the BMP sizing calculators, not tabulated as inches in the main narrative. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.sfpuc.gov/sites/default/files/documents/SMR_DesignGuide_May2016.pdf", "landing_page_url": "https://www.sfpuc.gov/construction-contracts/new-developments/stormwater-management", "retrieved_at": "2026-08-10T07:45:00.000Z", "original_filename": "san-francisco-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:03:10.393Z", "enrich_model": "composer-2.5:run-ebff62ae-cea3-45f5-94bd-3d853e377d39", "enrich_notes": "Provided corpus is mostly regulatory overview, BMP hierarchies, and Table 1 definitions; it references Appendix A for ponding depth, media depth, and maximum drawdown times but does not tabulate numeric values. Separate-sewer large projects size to 90th/85th percentile 24-hour storms (SFPUC/Port); combined-sewer cases use 1- and 2-year 24-hour storm performance—no explicit WQv depth in inches in these excerpts. Infiltration criteria are pointed to Appendix C without numeric separation or design infiltration rate here.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "san-jose-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/san-jose-ca/", "data_url": "https://stormwateratlas.com/data/manuals/san-jose-ca.json", "document_metadata": { "jurisdiction_name": "City of San Jose / Santa Clara Valley (SCVURPPP)", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "C.3 Stormwater Handbook", "version_or_edition": "October 2024", "adoption_or_effective_date": "2024-10", "last_revised_date": "2024-10", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "MRP Provision C.3.d numeric sizing: volume-based treatment sized for stormwater quality volume equal to 80% of annual runoff using the California Stormwater BMP Handbook Approach adapted for Santa Clara Valley (continuous simulation sizing curves in Appendix B; recommended over WEF/URQM). Alternate MRP option: WEF Urban Runoff Quality Management volume capture coefficients. Flow-based treatment sized per MRP C.3.d (including 85th percentile hourly intensity ranking method). Bioretention and flow-through planters may use flow-, volume-, or combination sizing. Regulated Projects typically create/replace ≥5,000 sf impervious (≥10,000 sf detached single-family; ≥1 acre road reconstruction).", "peak_flow_calculation_method": [ "MRP Provision C.3.d hydraulic sizing (flow-based, volume-based, or combination)", "Bay Area Hydrology Model (BAHM 2023) for hydromodification management / flow duration control where HM applies", "California Stormwater BMP Handbook Approach continuous simulation sizing curves (Santa Clara Valley rain gages)" ], "required_hydrologic_hydraulic_software": [ "Bay Area Hydrology Model (BAHM 2023) where hydromodification management sizing is required" ], "approved_bmp_categories": [ "Bioretention area", "Flow-through planter box", "Tree well filter", "Infiltration trench", "Subsurface infiltration system", "Rainwater harvesting and reuse", "Media filter (non-LID; Special Projects)", "Extended detention basin (non-LID)", "Pervious paving / self-treating and self-retaining areas", "Green roofs (site design / treatment guidance)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Campbell • Cupertino • Los Altos • Los Altos Hills • Los Gatos • Milpitas • Monte Sereno • Mountain View • Palo Alto San José • Santa Clara • Sunnyvale • Santa Clara County • Santa Clara Valley Water District", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Member agencies (Co-permittees) include Campbell, Cupertino, Los Altos, Los Altos Hills, Los Gatos, Milpitas, Monte Sereno, Mountain View, Palo Alto, San Jose, Santa Clara, Saratoga, Sunnyvale, the County of Santa Clara, and Valley Water.", "page_or_section": "Credits / Program background" }, { "field": "document_metadata.state_code", "excerpt": "discharge stormwater to South San Francisco Bay", "page_or_section": "Program background" }, { "field": "document_metadata.document_title", "excerpt": "rements . . . . . . . . . . 2- 1 2.1 Stormwater Issues in Developed Areas.................................................................2-1 2.2 Post-Construction Stormwater Controls ................................................................2-3 2.3 Municipal Stormwater", "page_or_section": "p. 4" }, { "field": "document_metadata.version_or_edition", "excerpt": "on May 22, 2022 and amended on October 11, 2023. New Development Land disturbing activities, construction or installation of a building or structure, creation of impervious surfaces, and/or land subdivision on a previously undeveloped site. Non-Stormwater Discharge Any d", "page_or_section": "p. 19" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "on May 22, 2022 and amended on October 11, 2023. New Development Land disturbing activities, construction or installation of a building or structure, creation of impervious surfaces, and/or land subdivision on a previously undeveloped site. Non-Stormwater Discharge Any d", "page_or_section": "p. 19" }, { "field": "document_metadata.last_revised_date", "excerpt": "on May 22, 2022 and amended on October 11, 2023. New Development Land disturbing activities, construction or installation of a building or structure, creation of impervious surfaces, and/or land subdivision on a previously undeveloped site. Non-Stormwater Discharge Any d", "page_or_section": "p. 19" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Guidance for Implementing Stormwater Requirements for New Development and Redevelopment Projects", "page_or_section": "Cover / subtitle" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Determine the stormwater quality volume equal to 80% of the annual runoff, in accordance with the methodology in Appendix D of the California Stormwater Best Management Practices Handbook (2003) using local rainfall data (known as the California BMP Handbook Approach).", "page_or_section": "Chapter 5 Volume-Based Sizing Criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Volume-based treatment measures should be designed to treat the stormwater quality volume equal to 80% of the annual runoff from the site, using the sizing curves in Appendix B specific to Santa Clara Valley conditions.", "page_or_section": "Chapter 5 Recommended Volume-Based Sizing Approach" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "A method of designing flow-based treatment controls that ranks long-term hourly rainfall intensities, selects the 85th percentile value", "page_or_section": "Glossary / flow-based sizing" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Bay Area Hydrology Model (BAHM 2023), developed by the Urban Runoff Program… The BAHM has been… sizing is in compliance with the MRP.", "page_or_section": "Hydromodification / BAHM discussion" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The BAHM 2023 may be downloaded at:", "page_or_section": "HM / BAHM section" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention area; Flow-through planter box; Tree well filter; Infiltration trench; Subsurface infiltration system; Rainwater harvesting and reuse; Media filter; Extended detention basin", "page_or_section": "Table 5-1" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention areas should have a minimum BSM depth of 18 inches.", "page_or_section": "Chapter 6, page 104" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "A minimum long term infiltration rate of 5 inches per hour is required", "page_or_section": "Chapter 6 bioretention, page 104" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "the outlet should be sized with a drawdown time of 48 hours for the design water quality volume", "page_or_section": "Chapter 6 extended detention, page 135" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "sized to capture the required water quality volume with a 48-hour detention time", "page_or_section": "Chapter 6 extended detention, page 134" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The extended detention basin should have a length to width ratio of at least 1.5:1.", "page_or_section": "Chapter 6, page 135" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "The product must be certified by the Washington State Technical Assessment Protocol – Ecology (TAPE) program", "page_or_section": "Chapter 6 tree well filters, page 115" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A 10-foot separation between the bottom of the trench and seasonal high groundwater levels is required", "page_or_section": "Chapter 6 infiltration trench, page 121" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Trenches may be designed to provide temporary storage of storm water, but should drain within 72 hours.", "page_or_section": "Chapter 6 infiltration trench, page 121" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention areas, or \"rain gardens,\" function as soil and plant-based filtration measures", "page_or_section": "Chapter 6.1, page 101" }, { "field": "practice_mentions.extended_detention", "excerpt": "Extended detention ponds (a.k.a. dry ponds or dry extended detention basins)", "page_or_section": "Chapter 6.8, page 134" }, { "field": "practice_mentions.green_roof", "excerpt": "Green roofs listed as site design measure in Table 2-1", "page_or_section": "Chapter 2, page 33" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales are no longer considered stand-alone LID treatment systems in the MRP.", "page_or_section": "Glossary, page xxi" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "SCVURPPP C.3 Handbook is the shared MRP C.3 design guidance for San Jose and other Santa Clara Valley co-permittees. Design storms are provision C.3.d / HM criteria rather than classical return-period drainage design; return-period list left empty. BAHM required for HM where applicable, not for all C.3 treatment sizing.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://scvurppp.org/wp-content/uploads/2024/11/SCVURPPP-C3-Handbook-chapters-2024-Oct-update.pdf", "landing_page_url": "https://scvurppp.org/2024/10/28/c-3-stormwater-handbook-2024/", "retrieved_at": "2026-08-10T07:50:00.000Z", "original_filename": "san-jose-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "TAPE", "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:03:49.166Z", "enrich_model": "composer-2.5:run-17c09d0e-b391-44e3-93bd-884df79f3b4d", "enrich_notes": "Volume-based treatment is sized for stormwater quality volume equal to 80% of annual runoff (California BMP Handbook Approach / Appendix B), not a single rainfall depth in inches. SHWT separation is stated as 5 ft (planters, pervious pavement, cisterns) or 10 ft (infiltration trench, subsurface infiltration drain rock)—no single handbook minimum. Drawdown limits include 48 h (extended detention WQV), 72 h (infiltration trenches/exfiltration), 48–72 h (subsurface galleries), and five days (general mosquito guidance).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "santa-barbara-ca", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/santa-barbara-ca/", "data_url": "https://stormwateratlas.com/data/manuals/santa-barbara-ca.json", "document_metadata": { "jurisdiction_name": "City of Santa Barbara", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "Storm Water BMP Technical Guidance Manual", "version_or_edition": "December 2020", "adoption_or_effective_date": null, "last_revised_date": "2020-12", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Tiered SWMP requirements by new/redeveloped impervious area. Tier 4: retain/prevent offsite discharge for storms up to the 95th percentile 24-hour rainfall event (currently 2.4\" for Santa Barbara); retain 1.2\" 24-hour for replaced impervious and 2.4\" for new impervious. Tier 3: peak runoff discharge rate and water quality treatment; volume reduction per Ch.6. Volume reduction that exceeds water quality treatment volume also satisfies treatment if BMPs treat runoff.", "peak_flow_calculation_method": [ "Peak runoff discharge rate matching for Tier 3/4", "BMP sizing worksheets (Ch.6)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention / planter boxes", "Permeable pavement", "Infiltration basins / trenches", "Rain barrels / cisterns", "Bioswales / vegetated BMPs", "Dry extended detention", "Other Ch.6 Storm Water Runoff BMPs" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Storm Water BMP Technical Guidance Manual", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "95th percentile 24-hour rainfall event, which is currently 2.4\" for Santa Barbara", "page_or_section": "§1.4 / Tier 4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "retain the 1.2\", 24-hour rainfall event for all replaced impervious area and the 2.4\", 24-hour rainfall event for all new impervious area", "page_or_section": "§6.2" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Design drawdown time hrs 72", "page_or_section": "Table 6-23, page 147" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time of gravel drainage layer hrs 72 (maximum)", "page_or_section": "Table 6-28, page 166" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting soil depth feet 2 minimum; 3 preferred", "page_or_section": "Table 6-3, page 81" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting soil depth shall be a minimum of 2 feet", "page_or_section": "Section 6.6.1.3, page 81" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Minimum/maximum ponding depth inches 3 minimum (6 preferred) /12 maximum", "page_or_section": "Table 6-3, page 81" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Depth without sediment storage feet 4 (first cell minimum)", "page_or_section": "Table 6-49, page 218" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Drawdown time for extended detention (over permanent pool) hours 48", "page_or_section": "Table 6-49, page 218" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "A drawdown time of 36 to 48 hours shall be provided for the water quality design volume, Vwq", "page_or_section": "Section 6.10.3, page 243" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The forebay shall be designed with a minimum length to width ratio of 2:1", "page_or_section": "Section 6.7.3, page 148" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "one-inch, 24-hr storm event ... or ... 2.4 inch, 24-hr storm event", "page_or_section": "Appendix D Bioretention Worksheet, page 284" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "infiltration rate measured be between 0.05 and 2.4 in/hr", "page_or_section": "Section 4.4, page 53" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Minimum 3\" for walkways and patios, and 12\" for vehicular areas", "page_or_section": "Table 6-28, page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Groundwater separation must be at least 5 feet between bottom of the basin, trench, or dry well and the measured seasonally high groundwater surface elevation", "page_or_section": "Section 6.7, page 146" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://sustainability.santabarbaraca.gov/sites/default/files/documents/Parks%20%26%20Recreation/Creeks/Final%20Guidance%20Manual.pdf", "landing_page_url": "https://santabarbaraca.gov/SWMP", "retrieved_at": "2026-08-10T10:42:30.501Z", "original_filename": "santa-barbara-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 3, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T10:04:36.500Z", "enrich_model": "composer-2.5:run-2a545aa7-b654-4852-825a-29e8e0080fa2", "enrich_notes": "Infiltration suitability range 0.05–2.4 in/hr (field measured); kdesign from measured rate divided by safety factor F per Appendix D. Tiered sizing uses 1-inch and 2.4-inch 24-hr storm volumes in Appendix D worksheets. Bioretention drawdown of planting soil is 48 hr; infiltration BMP design drawdown is 72 hr; permeable pavement gravel layer drawdown max 72 hr. SHWT separation is 2 ft (with underdrains) or 5 ft (without) for bioretention and permeable pavement; infiltration BMPs require 5 ft to SHWT at basin/trench/dry well bottom.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "santa-fe-nm", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/santa-fe-nm/", "data_url": "https://stormwateratlas.com/data/manuals/santa-fe-nm.json", "document_metadata": { "jurisdiction_name": "City of Santa Fe", "jurisdiction_level": "municipality", "state_code": "NM", "document_title": "Green Infrastructure and Low Impact Design Guide (Albuquerque/Bernalillo — NM municipal reference)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "No durable city design-manual PDF found. Using Albuquerque/Bernalillo GSI/LID Guide as New Mexico municipal green infrastructure reference for volume reduction / LID practices.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure / LID practices", "Infiltration / bioretention", "Harvest and use" ] }, "evidence": [ { "field": "design_parameters.max_drawdown_hours", "excerpt": "Requires permeable soils for infiltration in under 96 hours.", "page_or_section": "Glossary — Infiltration Trench (page 26)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Intended to release water into the soil within 96 hours.", "page_or_section": "Glossary — Passive Rainwater Harvesting (page 26)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of trench should be at least 3' above seasonal high water table", "page_or_section": "Type 2 Infiltration Trench DPM Detail 3.0 (page 9)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" minimum depth of planting soil mix, for low plantings only, and 24\" minimum for trees", "page_or_section": "Stormwater Planter Box DPM Detail 8.1 (page 16)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" minumum depth shown for planting soil mix for low plantings only, minimum depth for tree plantings should be increased To 24\"", "page_or_section": "Stormwater Curb Extension DPM Detail 5.1 (page 11)" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Regional NM GI placeholder — replace with city drainage criteria when found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://swefc.unm.edu/gardb/wp-content/uploads/2025/03/61-Green_Infrastructure_and_Low_Impact_Design_Guide_1-1.pdf", "landing_page_url": "https://www.bernco.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "santa-fe-nm.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:05:11.881Z", "enrich_model": "composer-2.5:run-bb11d078-69d4-476e-ad2d-28430a8deb37", "enrich_notes": "Santa Fe proxy uses Albuquerque/Bernalillo GSI/LID Guide; arid-context emphasis on bioinfiltration vs retention, 96-hour infiltration/dewatering norm, and SHWT separation for subsurface trenches. No explicit WQv depth or NM DOT-style numeric sizing in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "santa-rosa-ca", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/santa-rosa-ca/", "data_url": "https://stormwateratlas.com/data/manuals/santa-rosa-ca.json", "document_metadata": { "jurisdiction_name": "City of Santa Rosa", "jurisdiction_level": "municipality", "state_code": "CA", "document_title": "2020 Storm Water Low Impact Development Technical Design Manual", "version_or_edition": "2020", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Water quality design storm is 1.0 inch in a 24-hour period. Treatment: treat all runoff from impermeable surfaces generated by that storm. Delta Volume Capture: infiltrate/reuse any increase in runoff volume for the WQ storm (projects creating/replacing <1 acre impervious); hydromodification control for ≥1 acre requires capture and retention of 100% of post-development volume from 1.0\" rain over 24 hours. Volume calculations use the Curve Number Method.", "peak_flow_calculation_method": [ "Curve Number Method", "TR-55 (referenced)" ], "required_hydrologic_hydraulic_software": [ "Storm Water Calculator (Appendix C)" ], "approved_bmp_categories": [ "Rainwater harvesting", "Green roofs", "Interceptor trees", "Buffer strips", "Flow-through planters", "Downspout disconnects / impervious area disconnection", "Bioretention", "Pervious concrete / permeable pavement", "Detention (lower priority)", "Proprietary units (constrained sites)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Manual apply to projects within the jurisdiction of City of Santa Rosa, City of Healdsburg", "page_or_section": "Chapter 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Santa Rosa", "page_or_section": "Chapter 1" }, { "field": "document_metadata.state_code", "excerpt": "North Coast Regional Water Quality Control Board", "page_or_section": "Acronyms" }, { "field": "document_metadata.document_title", "excerpt": "2020 Storm Water Low Impact Development Technical Design Manual", "page_or_section": "TOC footer" }, { "field": "document_metadata.version_or_edition", "excerpt": "2020 Storm Water Low Impact Development Technical Design Manual", "page_or_section": "TOC footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This design manual is covered under the North Coast Regional Area (Region 1)", "page_or_section": "Acronyms — NCRWQCB" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The water quality design storm used for all SWLIDS calculations is 1.0 inch in a 24-hour period.", "page_or_section": "Chapter 6 — Design Requirements" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "All volume calculations are completed using the Curve Number Method", "page_or_section": "Chapter 6" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Storm Water Calculator located in Appendix C", "page_or_section": "Chapter 4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "rainwater harvesting, green roofs, interceptor trees, buffer strips, and flow through planters", "page_or_section": "Chapter 5 — Universal BMPs" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "100% volume capture is the capture and retention of 100% of the volume of runoff generated by 1.0\" of rain over a 24-hour period.", "page_or_section": "ACRONYMS, ABBREVIATIONS AND DEFINITIONS, page 14" }, { "field": "practice_mentions.bioretention", "excerpt": "BIORETENTION A-64", "page_or_section": "APPENDIX E table of contents, page 8" }, { "field": "practice_mentions.swale", "excerpt": "Examples of treatment controls include: vegetated swales, extended detention basins, vegetated buffer strips, Bioretention areas, and media filters.", "page_or_section": "ACRONYMS, ABBREVIATIONS AND DEFINITIONS, page 14" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Prepared from City DocumentCenter View/14974 (listed as 2017 narrative URL); extracted text headers identify the 2020 LID Technical Design Manual. Covers Santa Rosa and Sonoma County co-permittees geographically.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years" ] }, "source": { "document_url": "https://www.srcity.org/DocumentCenter/View/14974/2017-Storm-Water-Technical-Design-Manual-Narrative-revised-1621", "landing_page_url": "https://www.srcity.org/1255/Low-Impact-Development", "retrieved_at": "2026-08-10T09:11:27.297Z", "original_filename": "santa-rosa-ca.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:05:37.133Z", "enrich_model": "composer-2.5:run-841ca373-b639-4c1f-aa22-7a594ec35983", "enrich_notes": "Provided corpus is largely Appendix E table of contents plus Ch. 1 LID definition, Ch. 4 site assessment (2 ft seasonal high groundwater relative to BMP bottom—not stated as a minimum separation design value), and acronyms. Numeric BMP sizing appears on fact sheets A-21+ which are not in the excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "scottsdale-az", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/scottsdale-az/", "data_url": "https://stormwateratlas.com/data/manuals/scottsdale-az.json", "document_metadata": { "jurisdiction_name": "City of Scottsdale", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Design Standards & Policies Manual", "version_or_edition": "2018", "adoption_or_effective_date": "2018-02-20", "last_revised_date": "2018", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 50, 100 ], "water_quality_volume_method": "First Flush Volume V = CPA with P = 0.5 inches (converted to feet); retention of first flush encouraged if storage evacuated within 36 hours (Section 4-1.201). Broader stormwater storage requirements also referenced to SRC Chapter 37. Stormwater storage facilities designed primarily as detention facilities.", "peak_flow_calculation_method": [ "Grading & Drainage Chapter 4 standards", "100-year storm flooding / channel capacity criteria", "Street drainage design storm table (10-/25/50-/100-year)", "Detention / stormwater storage basin design" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater storage / detention basins", "Underground stormwater storage", "First flush retention", "Channel / wash conveyance" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Scottsdale", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Scottsdale", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Contractors shall provide a valid Arizona Registrar of Contractors (ROC) license number. The permit and permit inspection card shall remain on site for inspection at all times. Failure to produce the required permits will result in immediate suspension of all work until the", "page_or_section": "p. 38" }, { "field": "document_metadata.document_title", "excerpt": "DESIGN STANDARDS & POLICIES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "City of Scottsdale - 2018", "page_or_section": "Header" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "of options are often most effective. All dust control measures shall be maintained as appropriate to effectively control dust. Materials: i. Watering ii. Stabilization with gravel or decomposed granite iii. Stabilization with recycled asphalt paving iv. Stabilizatio", "page_or_section": "p. 84" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "SRC, Chapter 37 Stormwater and Floodplain Management", "page_or_section": "Chapter 4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-YEAR 25/50-YEAR 100-YEAR", "page_or_section": "Street drainage" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "P = the required precipitation depth of 0.5 inches, converted to feet", "page_or_section": "First Flush Volume" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Stormwater storage facilities shall be designed primarily as detention facilities", "page_or_section": "4-1.201" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "STORMWATER STORAGE / DETENTION BASINS", "page_or_section": "Chapter 4 TOC" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = the required precipitation depth of 0.5 inches, converted to feet", "page_or_section": "GRADING & DRAINAGE 4-1.201, page 186" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "positive outflow pipe that can drain the facility within 36 hours", "page_or_section": "STORMWATER STORAGE 4-1.201 Rating 1, page 184" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The applicant can illustrate the basin(s) will drain within 36 hours", "page_or_section": "STORMWATER STORAGE 4-1.201 Rating 2, page 184" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Retention of the first flush volume is encouraged, if the stormwater storage facility will be fully evacuated within 36 hours", "page_or_section": "Section 4-1.201 First Flush, page 187" }, { "field": "practice_mentions.extended_detention", "excerpt": "Stormwater storage facilities shall be designed primarily as detention facilities.", "page_or_section": "STORMWATER STORAGE 4-1.201 GENERALLY, page 184" }, { "field": "practice_mentions.extended_detention", "excerpt": "Rating 1 – Detention Basins", "page_or_section": "Section 4-1.201, page 184" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Rating 2 – Retention Basins Utilizing Basin Floor Percolation", "page_or_section": "Section 4-1.201, page 184" }, { "field": "practice_mentions.swale", "excerpt": "Refer to Figure 4-1.3, Typical Cross Section for Roadside Swales", "page_or_section": "Section 4-1.204, page 195" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "DSPM 2018 truncated text extract; first-flush and storage criteria confirmed. Full Chapter 37 numeric storage may live in code. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://ww2.scottsdaleaz.gov/Assets/ScottsdaleAZ/Design/DSPM/DSPM+2018.pdf", "landing_page_url": "https://www.scottsdaleaz.gov/design/dspm", "retrieved_at": "2026-08-10T08:24:40.117Z", "original_filename": "scottsdale-az.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 36, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T10:07:15.167Z", "enrich_model": "composer-2.5:run-8d475cd2-d5d3-440b-abf7-04cac73aed1f", "enrich_notes": "First flush WQ storage uses V=CPA with P=0.5 in; retention encouraged if fully evacuated within 36 h (Section 4-1.201). Primary preference is detention basins with positive outflow draining within 36 h; retention via basin-floor percolation is secondary (Rating 2) with same 36 h drain requirement and FCDMC double-ring infiltrometer testing. Full-storage facility drain times stated as generally 12–24 h (design guidance, not ED-specific). Parking-lot storage max water depth 6 in. Outflow invert typically 3 in above basin floor. Broader volume requirements referenced to SRC Chapter 37 (not in excerpt).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "scranton-pa", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/scranton-pa/", "data_url": "https://stormwateratlas.com/data/manuals/scranton-pa.json", "document_metadata": { "jurisdiction_name": "City of Scranton", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual / Act 167", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "PA PCSM Manual pollutant-load approach coupling volume and water quality management; Act 167 / MS4 ordinances require BMPs consistent with Pennsylvania Stormwater BMP / PCSM Manual.", "peak_flow_calculation_method": [ "PA PCSM / Stormwater BMP Manual methods", "Act 167 stormwater management ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Volume-reducing SCMs", "Water quality SCMs", "Post-construction BMPs per PA Manual" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Scranton MS4 / Act 167 cites PA PCSM Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DRAFT / Page 1-3 1.1 OVERVIEW OF PCSM MANUAL This PCSM Manual establishes DEP-approved procedures for conducting PCSM stormwater analyses and provides SCM standards that can be used for regulatory compliance under Chapter 102. These procedures and standards may be applied to he", "page_or_section": "p. 12" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / page B-31" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance Above SHWT 2 ft", "page_or_section": "Table 3-90 / page 388" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil Media Depth Min. ... Min. 18 in", "page_or_section": "Table 3-90 (3.5.1 Bioinfiltration, 3.6.1 Bioretention) / page 388" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil media depth should be at least 18 inches.", "page_or_section": "Section 3.4.6 Vegetated Conveyance / page 174" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum Ponding/Storage Depth ... 2 ft", "page_or_section": "Table 3-90 (3.6.1 Bioretention) / page 388" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Permeable pavement materials with greater than or equal to one foot of storage underneath are considered permeable pavement systems with underground storage", "page_or_section": "Section 3.5.3 / page 204" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Section 3.8.1 Wet Basin / page 364" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Temporary pool should draw down to the permanent pool elevation within three days.", "page_or_section": "Section 3.8.1 Wet Basin / page 364" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length to width ratio should be at least two to one.", "page_or_section": "Section 3.6.6 Engineered Stormwater Treatment Wetland / page 283" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The length to width ratio of the basin should be a minimum of 2:1 to avoid short circuiting.", "page_or_section": "Section 3.8.1 Wet Basin / page 364" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Soil Media Depth Min. ... Min. 3 in", "page_or_section": "Table 3-90 (3.6.2 Green Roof) / page 388" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Maximum Ponding Time ... 72 hrs", "page_or_section": "Table 3-90 (3.8.2 Naturalized Detention Basin) / page 388" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via PA PCSM Manual (Allentown/Harrisburg pattern). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_parameters.shwt_separation_inches" ] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "scranton-pa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:08:08.374Z", "enrich_model": "composer-2.5:run-08b3b1f7-90d5-47ce-ad13-95211ad59e52", "enrich_notes": "PA PCSM Manual (Act 167); Scranton follows state PCSM guidance. WQ sizing uses 1.2-inch/2-hour rainfall for permanent pool and MRC examples; infiltration suitability thresholds cite 0.25 and 0.4 in/hr (classification, not a single design rate). Table 3-90 consolidates ponding times (often 72–96 hr), media mins, and 2 ft SHWT separation for infiltration SCMs.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "seattle-wa-2026", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/seattle-wa-2026/", "data_url": "https://stormwateratlas.com/data/manuals/seattle-wa-2026.json", "document_metadata": { "jurisdiction_name": "City of Seattle", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Manual", "version_or_edition": "Joint Directors' Rule Public Utilities DWW-200 (rev. 3) / Department of Construction & Inspections 03-2026", "adoption_or_effective_date": "2026-07-01", "last_revised_date": null, "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "The daily runoff volume at or below which 91 percent of the total runoff volume for the simulation period occurs, determined by ranking daily runoff volumes and sequentially summing them until the total equals 9 percent of the total volume.", "peak_flow_calculation_method": [ "Single Event Hydrograph Method", "Continuous Simulation Method", "Rational Method" ], "required_hydrologic_hydraulic_software": [ "Western Washington Hydraulic Model (WWHM)", "MGSFlood" ], "approved_bmp_categories": [ "Soil Amendment", "Tree Planting and Retention", "Dispersion BMPs", "Infiltration BMPs", "Rainwater Harvesting BMPs", "Alternative Surface BMPs", "Detention BMPs", "Non-infiltrating BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Seattle", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Seattle", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Washington State Department of Ecology", "page_or_section": "1.1" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "JOINT DIRECTORS’ RULE\nPublic Utilities DWW-200 (rev. 3)\nDepartment of Construction & Inspections 03-2026", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "which Ecology has determined meets the requirements contained in the Phase I NPDES Municipal Stormwater Permit, with reference to the Stormwater Management Manual for Western Washington (SWMMWW)", "page_or_section": "1.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year, 5-year, 10-year, 25-year, 50-year, and 100-year recurrence intervals", "page_or_section": "3.8, 5.3, 5.3.5, 4.3.6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The daily runoff volume at or below which 91 percent of the total runoff volume for the simulation period occurs, as determined using an approved continuous model.", "page_or_section": "5.4.1.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Single Event Hydrograph Method, Continuous Simulation Method, Rational Method", "page_or_section": "4.3.6" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "the Western Washington Hydraulic Model (WWHM) can be used to size flow control... The same design steps can generally be used for MGSFlood", "page_or_section": "4.4.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Soil Amendment, Tree Planting and Retention, Dispersion BMPs, Infiltration BMPs, Rainwater Harvesting BMPs, Alternative Surface BMPs, Detention BMPs, Non-infiltrating BMPs", "page_or_section": "Volume 3 Table of Contents" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The surface pool drawdown time must be a maximum of 24 hours (drain time is calculated as the maximum ponding depth divided by the subgrade soil design infiltration rate).", "page_or_section": "Volume 3, Chapter 5, Section 5.4.4 Ponding Area, page 5-69 (420)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The rain garden soil depth must be a minimum of 12 inches.", "page_or_section": "Volume 3, Chapter 5, Section 5.4.5, page 5-96 (447)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The average ponding depth must be no less than 2 inches. The ponding depth must be no more than 12 inches unless it meets the maximum drawdown time criteria and is approved by the Director.", "page_or_section": "Volume 3, Chapter 5, Section 5.4.4 Ponding Area, page 5-69 (420)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Table 3.3. Minimum Measured Infiltration Rates. (multiple BMP-specific minimums in in/hr, e.g., Infiltration Trenches 2, Drywells 5, Infiltrating Bioretention without underdrain 0.6)", "page_or_section": "Volume 3, Chapter 3, Table 3.3, page 3-12 (311)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Minimum Vertical Separation (ft) Groundwater … Infiltrating Bioretention without Underdrain … Wet Season … 3 … Permeable Pavement Facilities … Wet Season … 1", "page_or_section": "Appendix D, Comprehensive Subsurface Investigation Elements, page D-6 (840)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "All fields were successfully mapped based on direct, explicit text references. No interpolation or estimation was used. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.seattle.gov/documents/departments/sdci/codes/stormwatercode/2026stormwatermanualcombined.pdf", "landing_page_url": "https://www.seattle.gov/sdci/codes/codes-we-enforce-(a-z)/stormwater-code", "retrieved_at": "2026-08-07T11:41:19.738Z", "original_filename": "seattle-wa-2026.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:09:24.326Z", "enrich_model": "composer-2.5:run-fe6161d3-2334-43fc-b179-efc2cdf6d9fd", "enrich_notes": "WQv is defined as a daily runoff volume threshold (91st-percentile volume method), not an inch depth in the provided excerpts. Minimum measured infiltration rates vary by BMP in Table 3.3 (e.g., 0.3–5 in/hr); Appendix D vertical separation to groundwater is given in feet by BMP type and season, not as a single inches value. Bioretention ponding rules state minimum average depth 2 in and maximum 12 in (6 in in high-pedestrian ROW), so no single ponding depth was assigned.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "seattle-wa", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/seattle-wa/", "data_url": "https://stormwateratlas.com/data/manuals/seattle-wa.json", "document_metadata": { "jurisdiction_name": "City of Seattle", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Manual", "version_or_edition": "July 2021", "adoption_or_effective_date": "2021-07-01", "last_revised_date": "2021-03-23", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "The daily runoff volume at or below which 91 percent of the total runoff volume for the simulation period occurs, as determined using an approved continuous model.", "peak_flow_calculation_method": [ "Continuous Simulation Method", "Single Event Hydrograph Method", "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "On-site stormwater management", "Flow control", "Water quality treatment", "Conveyance", "Soil amendment", "Tree planting and retention", "Dispersion", "Infiltration", "Rainwater harvesting", "Alternative surface", "Detention", "Non-infiltrating" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Seattle", "page_or_section": "Page 2 of 1086" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Seattle", "page_or_section": "Page 2 of 1086" }, { "field": "document_metadata.state_code", "excerpt": "Washington State Department of Ecology", "page_or_section": "Volume 1, Chapter 1, Page 1-1" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Manual", "page_or_section": "Page 2 of 1086" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Ecology has determined to meet the requirements contained in the Phase I NPDES Municipal Stormwater Permit, with reference to the Stormwater Management Manual for Western Washington (Ecology 2019).", "page_or_section": "Volume 1, Chapter 1, Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year, 5-year, 10-year, 25-year, 50-year, 100-year", "page_or_section": "Volume 1 & Volume 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The daily runoff volume at or below which 91 percent of the total runoff volume for the simulation period occurs, as determined using an approved continuous model.", "page_or_section": "Volume 1, Chapter 5, Page 5-14" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Single Event Hydrograph Method... Continuous Simulation Method... Rational Method", "page_or_section": "Volume 3, Chapter 4, Page 4-46 & Page 4-65" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "This volume covers four primary functional categories of stormwater BMPs: On-site stormwater management, Flow control BMPs, Water quality treatment BMPs, Conveyance BMPs", "page_or_section": "Volume 3, Chapter 2, Page 2-1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The surface pool drawdown time shall be a maximum of 24 hours", "page_or_section": "Volume 3, Section 5.4.4 Infiltrating Bioretention, page 402 (5-70)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Pool Drawdown Time: The surface pool drawdown time for maximum ponding depth shall be less than 24 hours after water has ceased being added to the BMP.", "page_or_section": "Appendix D, Section D-8.1, page 779 (D-17)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The average ponding depth shall be no less than 2 inches. The ponding depth shall be no more than 12 inches.", "page_or_section": "Volume 3, Section 5.4.4 Ponding Area, page 402" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches 5 5 ... Infiltrating Bioretention without underdrain 0.6 0.6 ... Infiltrating Bioretention with underdrain 0.3", "page_or_section": "Table 3.3 Minimum Measured Infiltration Rates, page 294" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Minimum Vertical Separation (ft) Groundwater ... Infiltrating Bioretention without Underdrain ... Wet Season ... 3 ... Dry Season ... 8", "page_or_section": "Appendix D Comprehensive Subsurface Investigation, page 768 (D-6)" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Proprietary and Emerging Water Quality Treatment Technologies — refer to Section 5.8.11", "page_or_section": "Volume 3, Section 3.5.2.4 Basic Treatment, page 309" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.seattle.gov/documents/Departments/SDCI/Codes/ChangesToCodes/UpdatingStormwaterRegulations/2021SWFullManualFinalClean.pdf", "landing_page_url": "https://www.seattle.gov/sdci/codes/codes-we-enforce-(a-z)/stormwater-code", "retrieved_at": "2026-08-07T11:39:56.302Z", "original_filename": "seattle-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:10:04.051Z", "enrich_model": "composer-2.5:run-1532e353-8a47-4a36-868b-de5bf91de0b9", "enrich_notes": "Seattle WQv is defined via continuous simulation (91% of runoff volume), not as an inch depth in the provided excerpts. Bioretention ponding: average depth not less than 2 in, maximum 12 in (6 in max in some ROW). Minimum measured infiltration rates in Table 3.3 (e.g., 5 in/hr trenches, 0.6 in/hr infiltrating bioretention without underdrain, 0.3 in/hr with underdrain); design rate is corrected measured rate per Appendix D, not a fixed manual value. Vertical separation to groundwater is BMP- and season-specific in Appendix D (e.g., 1–8 ft), with separate 10 ft and 15 ft investigation thresholds in Section 3.2. Infiltration trenches/drywells require site measured rate at least 5 in/hr for On-site List (Section 2.5). Proprietary technologies referenced without naming TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "shreveport-la", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/shreveport-la/", "data_url": "https://stormwateratlas.com/data/manuals/shreveport-la.json", "document_metadata": { "jurisdiction_name": "City of Shreveport", "jurisdiction_level": "municipality", "state_code": "LA", "document_title": "Drainage Design Standards", "version_or_edition": "October 14, 2021", "adoption_or_effective_date": "2021-10-14", "last_revised_date": "2021-10-14", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 100 ], "water_quality_volume_method": "Detention basins reduce post-development peak flow to pre-development for the 10-, 25-, and 100-year design storms. Design frequencies (Table 2-1): storm sewers/inlets 10-year; main channels / arterial cross drains / detention features 25-year; 100-year hydraulic gradient in SFHA and critical arterial underpasses. Rational Method ≤200 ac; NRCS 200–2,000 ac.", "peak_flow_calculation_method": [ "Rational Method (≤200 acres)", "NRCS Method (200–2,000 acres)", "USGS Method (>2,000 acres)", "Detention routing for 10-/25-/100-year storms" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater detention basins", "Retention features", "Storm sewers and inlets", "Open channels / main drainage channels", "Cross drains / side drains" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Engineering & Environmental Services Department www.shreveport.la.gov", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "DRAINAGE DESIGN STANDARDS", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "October 14, 2021", "page_or_section": "Cover" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Storm Sewers and Inlets ... 10-yr; Main Drainage Channels 25-yr; Detention or Retention Features 25yr; 100-year frequency storm ... SFHA", "page_or_section": "Table 2-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "reducing peak flow of a post-development site to peak flow the pre-development ... 10-year, 25-year, and 100-year design storms", "page_or_section": "§9 Stormwater Detention" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent city drainage design standards", "page_or_section": "Coverage note" }, { "field": "practice_mentions.extended_detention", "excerpt": "Section 9 Stormwater Detention 9-1 ... 9.3 Minimum Requirements for Detention Basin Design", "page_or_section": "Table of Contents / Section 9" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Examples of green infrastructure ... permeable pavement, green roofs, bioswales/stormwater parks", "page_or_section": "Section 11.2 Green Infrastructure Types, page 317" }, { "field": "practice_mentions.green_roof", "excerpt": "Examples of green infrastructure ... permeable pavement, green roofs, bioswales/stormwater parks", "page_or_section": "Section 11.2 Green Infrastructure Types, page 317" }, { "field": "practice_mentions.swale", "excerpt": "Inlets can be placed in roadside ditches, grass or lined swales, parking or pavement area depressions", "page_or_section": "Section 4.4 Inlet Placement, page 78" }, { "field": "practice_mentions.bioretention", "excerpt": "rain gardens/bioretention, cisterns and rainfall harvesting devices, subsurface infiltration", "page_or_section": "Section 11.2 Green Infrastructure Types, page 317" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Large standards PDF (324 pages / many detail sheets); WQ focus is primarily peak detention rather than fixed rainfall-depth WQv.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.shreveportla.gov/DocumentCenter/View/29000", "landing_page_url": "https://www.shreveportla.gov/2774/Engineering", "retrieved_at": "2026-08-10T09:45:18.880Z", "original_filename": "shreveport-la.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:10:21.747Z", "enrich_model": "composer-2.5:run-871e7d38-d391-4f9a-8c31-745039cfd27f", "enrich_notes": "Provided excerpts include Section 9 stormwater detention (TOC and section titles only; no numeric basin criteria in corpus). Section 11 Green Infrastructure lists example GI types (permeable pavement, green roofs, bioswales, rain gardens/bioretention, subsurface infiltration) with EPA descriptive text but no local numeric design parameters. Hydrology excerpt limits Rational Method to sites 200 acres or less. Atlas context indicates WQ/control via detention peak-matching for 10-, 25-, and 100-year storms rather than a stated WQv rainfall depth; Table 2-1 frequencies are not included in corpus excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "sioux-falls-sd", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/sioux-falls-sd/", "data_url": "https://stormwateratlas.com/data/manuals/sioux-falls-sd.json", "document_metadata": { "jurisdiction_name": "City of Sioux Falls", "jurisdiction_level": "municipality", "state_code": "SD", "document_title": "SDDOT Erosion and Sediment Control and Stormwater Management Course Manual (partial)", "version_or_edition": "Revised October 2024", "adoption_or_effective_date": null, "last_revised_date": "2024-10", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Erosion Control BMPs", "Sediment Control BMPs", "Slope / channel velocity controls", "Stabilized construction entrance" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Sioux Falls — partial coverage via SDDOT ESC/stormwater course manual (city design PDF 403)", "page_or_section": "Coverage note" }, { "field": "practice_mentions.swale", "excerpt": "open vegetated swales, natural depressions to allow infiltration of runoff onsite", "page_or_section": "5.3 SWPPP Contents / page 95" }, { "field": "practice_mentions.swale", "excerpt": "they improve the efficiency of other sediment controls, such as vegetated swales, filter strips, or infiltration devices", "page_or_section": "Slope Flow Control / page 16" }, { "field": "practice_mentions.swale", "excerpt": "Check dams – are small dams constructed in an open channel, swale, or ditch.", "page_or_section": "Channel Velocity Control / page 17" }, { "field": "practice_mentions.wet_pond", "excerpt": "structural stormwater management practices such as stormwater ponds, open vegetated swales", "page_or_section": "5.3 Post-Construction Stormwater Management / page 95" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Check dams are generally placed in areas where the slope is 6% or greater", "page_or_section": "Channel Velocity Control / page 17" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "ESC-focused state course manual — not a full municipal post-construction design manual.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://dot.sd.gov/media/kywakwy4/escontrolsw.pdf", "landing_page_url": "https://danr.sd.gov/", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "sioux-falls-sd.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:10:35.062Z", "enrich_model": "composer-2.5:run-cea31b98-162e-4bc1-baf8-3db7ebb8913e", "enrich_notes": "Corpus is SDDOT erosion/sediment control and construction general permit material (SWPPP, inspections, dewatering). Post-construction stormwater is referenced only generically (stormwater ponds, open vegetated swales, infiltration/natural depressions) without numeric SCM sizing, WQv depth, drawdown, or media depths. Check dam text cites 6% channel/slope threshold and 50-foot natural buffer; neither maps to requested design parameter fields.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "south-bend-in", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/south-bend-in/", "data_url": "https://stormwateratlas.com/data/manuals/south-bend-in.json", "document_metadata": { "jurisdiction_name": "City of South Bend", "jurisdiction_level": "municipality", "state_code": "IN", "document_title": "Indiana Storm Water Quality Manual (city MS4 / IDEM reference)", "version_or_edition": "October 2007", "adoption_or_effective_date": "2007-10-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Treat at least one-half inch of storm water runoff (water quality volume or storage) from impervious surfaces, targeting ≥80% TSS removal on an annual average basis; post-development peak discharge rates and volumes should not exceed predevelopment levels.", "peak_flow_calculation_method": [ "Rational Method", "NRCS TR-55", "NRCS TR-20" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Swales", "Filter Strip / Filter Ridge", "Bioretention Systems", "Infiltration Trench / Basin", "Dry Extended Detention / Wet Detention", "Constructed Storm Water Wetlands", "Pervious pavement systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "South Bend MS4 references Indiana Storm Water Quality Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treat at least one-half inch of storm water runoff", "page_or_section": "Indiana Storm Water Quality Manual" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume (WQV). The volume of runoff generated by one inch of rainfall on a site.", "page_or_section": "Appendix A — Glossary, page 734" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The pond should contain a low-flow drain with an adjustable gate valve allowing for gradual discharge. Recommended drawdown is 24 hours.", "page_or_section": "Chapter 8, Wet Detention Ponds, Table 3, page 639" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of the basin > 3 feet above the seasonal high water table depth", "page_or_section": "Chapter 8, Infiltration Basin, Table 2, page 609" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the bioretention area should be three feet or more above the seasonal high water table", "page_or_section": "Chapter 8, Bioretention Systems, page 619" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Aeration and drainage for planting bed is provided by a 12 to 20-inch deep sand and/or gravel bed.", "page_or_section": "Chapter 8, Bioretention Systems, Table 2, page 620" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Any system wider than 20 feet should be at least twice as long to evenly distribute the flow.", "page_or_section": "Chapter 8, Bioretention Systems, page 619" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via Indiana Storm Water Quality Manual (Evansville pattern).", "fields_not_found": [] }, "source": { "document_url": "https://www.inafsm.net/assets/docs/indiana%20storm%20water%20quality%20manual.pdf", "landing_page_url": "https://www.in.gov/idem/stormwater/resources/indiana-storm-water-quality-manual/", "retrieved_at": "2026-08-10T10:10:49.504Z", "original_filename": "south-bend-in.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:11:25.898Z", "enrich_model": "composer-2.5:run-683478f6-f51e-4e75-b5fd-612574f427de", "enrich_notes": "Atlas (South Bend) cites treating at least 0.5 inch of runoff from impervious surfaces; manual glossary defines WQV as runoff from one inch of rainfall. Small-storm treatment sizing for pervious pavement, infiltration trench, and infiltration basin references typically 0.5–1.5 inches (not a single mandated depth). SHWT separation of 3 feet appears for bioretention, infiltration basin, infiltration trench, porous pavement reservoirs, wet ponds, and constructed wetlands. Bioretention ponding recommended 6–9 inches (range only). Wet extended detention variant releases over 12–48 hours (range only).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "south-salt-lake-ut", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/south-salt-lake-ut/", "data_url": "https://stormwateratlas.com/data/manuals/south-salt-lake-ut.json", "document_metadata": { "jurisdiction_name": "City of South Salt Lake", "jurisdiction_level": "municipality", "state_code": "UT", "document_title": "South Salt Lake Stormwater Design Manual", "version_or_edition": "July 2020", "adoption_or_effective_date": "2020-07", "last_revised_date": "2020-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 50, 100 ], "water_quality_volume_method": "80th percentile storm volume using 0.6-inch precipitation depth (d80) with volumetric runoff coefficient (Reese or NRCS soil group method); V80 = RV × d80 × A.", "peak_flow_calculation_method": [ "Rational Method", "NRCS Curve Number Method (TR-55)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Cells", "Bioswales", "Rain Gardens", "Tree Box Filters", "Vegetated Strips", "Detention Ponds", "Retention Ponds", "Low Impact Development BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "THE CITY OF SOUTH SALT LAKE", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The City of South Salt Lake implemented ordinances for storm water management", "page_or_section": "Section 1.3, Page 1" }, { "field": "document_metadata.state_code", "excerpt": "The State of Utah MS4 Permit", "page_or_section": "Section 1.2, Page 1" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER DESIGN MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The federal, state, and local regulations shall be followed for all stormwater discharge and design.", "page_or_section": "Chapter 1, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The City of South Salt Lake requires 100 years 24 hours storm event for the new development/re-development hydrology calculations... Table 5-1 South Salt Lake City 24-hr Storm Event Intensity Rate... 10-year* 25-year* 50-year* 100-year", "page_or_section": "Section 5.2 and Table 5-1, Pages 5-9 to 5-10" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For new developments, the new MS4 permit requires 80th percentile storm precipitation for the total disturbed area... 80th Percentile: 0.6 inches... V80 = RV × d80 × A", "page_or_section": "Sections 3.1 and 3.2, Pages 3-4 to 3-5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The City of South Salt Lake allows Rational Method and SCS Curve Number Method (NRCS TR-55 Hydrology Design Method) for the design of hydrology system.", "page_or_section": "Section 5.1, Page 5-9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Sheet BR – Bioretention Cell... Sheet BS – Bioswale... Sheet RG – Rain Garden... Sheet TB – Tree Box Filters... Sheet VS – Vegetated Strips", "page_or_section": "Appendix A, Page 15" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "80th Percentile: 0.6 inches", "page_or_section": "Chapter 3, §3.1 80th Percentile Volume, page 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Percentile Precipitation Depth\n80th Percentile: 0.6 inches", "page_or_section": "Chapter 4, §4.1 80th Percentile Volume, page 9" }, { "field": "practice_mentions.bioretention", "excerpt": "Sheet BR – Bioretention Cell ... Sheet RG – Rain Garden", "page_or_section": "Appendix A Post Construction BMPs, page 18" }, { "field": "practice_mentions.swale", "excerpt": "Sheet BS – Bioswale ... Sheet VS – Vegetated Strips", "page_or_section": "Appendix A Post Construction BMPs, page 18" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Sheet TB – Tree Box Filters", "page_or_section": "Appendix A Post Construction BMPs, page 18" }, { "field": "practice_mentions.extended_detention", "excerpt": "LID BMP ApplicationsRetained Volume\nDetention Pond Retention Pond", "page_or_section": "Figure 3-1 Design Process Flowchart for New Development, page 8" }, { "field": "practice_mentions.wet_pond", "excerpt": "Detention Pond Retention Pond", "page_or_section": "Figure 3-1 / Figure 4-1 flowcharts, pages 8 and 11" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Compact manual with explicit 80th percentile 0.6-inch volume method, 100-year 24-hour design storm, Rational/TR-55 methods, and post-construction BMP appendix. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://sslc.gov/DocumentCenter/View/475/South-Salt-Lake-Stormwater-Design-Manual-PDF", "landing_page_url": "https://sslc.gov/", "retrieved_at": "2026-08-08T01:05:00.000Z", "original_filename": "south-salt-lake-ut.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:12:57.119Z", "enrich_model": "composer-2.5:run-89586ea7-b4a5-4e33-a340-3d60b41a9dcb", "enrich_notes": "Volume control uses 80th percentile precipitation depth d80 = 0.6 in with V80 = RV × d80 × A (Reese or NRCS soil-group RV). Site hydrology uses 100-year 24-hour storm; allowable discharge 0.2 cfs/acre. Appendix A lists post-construction BMP sheets (BR, BS, RG, TB, VS) but appendix body pages in corpus are blank—no facility sizing parameters extracted. Geotechnical report must highlight infiltration rate for onsite retention; no numeric design infiltration rate stated.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "springfield-il", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/springfield-il/", "data_url": "https://stormwateratlas.com/data/manuals/springfield-il.json", "document_metadata": { "jurisdiction_name": "City of Springfield", "jurisdiction_level": "municipality", "state_code": "IL", "document_title": "Illinois Model Stormwater Management Ordinance (capital MS4 template reference)", "version_or_edition": "September 2015", "adoption_or_effective_date": null, "last_revised_date": "2015-09", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "IL Model Stormwater Management Ordinance / Illinois Urban Manual BMP framework. Site runoff controls for large storms through the 100-year event with post-development discharge rates not exceeding pre-development for specified events. Minor storm sewers/inlets/swales designed for the 10-year critical duration storm; BMPs per Illinois Urban Manual.", "peak_flow_calculation_method": [ "Hydrologic methods allowed by ordinance (e.g., HEC-HMS)", "10-year critical duration for minor conveyance", "100-year site runoff / flood controls" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Illinois Urban Manual BMPs", "Detention / retention", "Storm sewers and swales", "Erosion and sediment controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Local Government, may be granted using criteria more permissive than the requirements contained in this ordinance. F. In a flood-prone area or a regulatory floodplain (without a mapped regulatory floodway) where the tributary drainage area is 640 acres or more, a variance", "page_or_section": "p. 57" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "10-year critical duration storm shall be used as a minimum for the design of storm sewers, storm inlets, and minor swales", "page_or_section": "IL Model Ordinance §506" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The basin must be designed to dewater within 72 hours following the end of the 100-year critical duration storm event.", "page_or_section": "504.0 Detention Facilities / 17.A (ORDINANCE COMMENTARY p.32)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration basin must be at least four (4) feet above the seasonal high groundwater elevation.", "page_or_section": "504.0 Detention Facilities / 17.F (ORDINANCE COMMENTARY p.33)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The underlying soils must have an infiltration rate of at least 0.5 inches per hour as determined by an engineer.", "page_or_section": "504.0 Detention Facilities / 17.B (ORDINANCE COMMENTARY p.32)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum depth of 24 inches between the bottom of the facility and the infiltration horizon", "page_or_section": "505.0 Non-Structural BMPs / 2.A (ORDINANCE COMMENTARY p.33)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Infiltration basins may be used as detention facilities subject to the following:", "page_or_section": "504.0 Detention Facilities / 17 (p.32-33)" }, { "field": "practice_mentions.swale", "excerpt": "The 10-year critical duration storm shall be used as a minimum for the design of storm sewers, storm inlets, and minor swales.", "page_or_section": "506.0 Stormwater Conveyance Systems / 1.A (p.34)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "For new permeable pavement, designers should use one-half of the measured infiltration rate during design", "page_or_section": "402.0 / 8.D (ORDINANCE COMMENTARY p.24)" }, { "field": "practice_mentions.green_roof", "excerpt": "Approaches may include green roofs, naturalized detention facilities, trees and tree boxes, rain gardens, vegetated swales", "page_or_section": "Green Infrastructure definition (p.13)" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Placeholder statewide model ordinance — replace when City of Springfield publishes a local drainage/stormwater design manual PDF.", "fields_not_found": [] }, "source": { "document_url": "https://dnr.illinois.gov/content/dam/soi/en/web/dnr/waterresources/documents/il-model-stormwater-ordinance.pdf", "landing_page_url": "https://dnr.illinois.gov/waterresources/stormwatermanagement.html", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "springfield-il.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:13:54.811Z", "enrich_model": "composer-2.5:run-39f8de7a-c10d-4388-8384-368266366a42", "enrich_notes": "Source is IDNR/OWR Model Stormwater Management Ordinance (Springfield placeholder). BMP design details defer to Illinois Urban Manual (Oct 2013). Appendix A credits use 0.25 inch runoff depth for non-structural volume reduction, not stated as a standalone WQV design depth. Infiltration BMPs require 24 inches minimum between facility bottom and infiltration horizon (505.2.A), distinct from 4 ft seasonal high groundwater separation for infiltration basins.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "springfield-ma", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/springfield-ma/", "data_url": "https://stormwateratlas.com/data/manuals/springfield-ma.json", "document_metadata": { "jurisdiction_name": "City of Springfield", "jurisdiction_level": "municipality", "state_code": "MA", "document_title": "Massachusetts Stormwater Management Handbook (city follows MassDEP Standards)", "version_or_edition": "Third Edition / 2023 draft handbook mirror", "adoption_or_effective_date": null, "last_revised_date": "2023-12", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Required runoff depth multiplied by total post-construction impervious site area (MassDEP Stormwater Management Standards / Handbook). Includes recharge, TSS removal, and peak-rate attenuation standards.", "peak_flow_calculation_method": [ "NRCS Technical Release WinTR20 Project Formulation Method", "WinTR55 Small Watershed Hydrology Method" ], "required_hydrologic_hydraulic_software": [ "WinTR-20", "WinTR-55" ], "approved_bmp_categories": [ "Non-Structural", "Structural Pretreatment", "Structural Treatment", "Structural Conveyance", "Structural Infiltration", "Structural Other" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Springfield follows MassDEP Stormwater Handbook / Standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Performance Removal Curves and the MassDEP pollutant removal credits – i.e., the EPA-PRCs and MassDEP pollutant removal credits assume that the SCM has been designed with proper pretreatment in accordance with the Appendix A Structural SCM Specifications and the Massachusett", "page_or_section": "p. 30" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "calculated as the required runoff depth multiplied by the total post-construction impervious site area", "page_or_section": "MassDEP Handbook" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Required WQv is at least 1.0 inch times the total impervious area of the post-development site.", "page_or_section": "Table 2-4d / springfield-ma-c0017, page 47" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Media Filters must be sized to treat the water quality volume (1.0 inch)", "page_or_section": "Appendix A Media Filter / springfield-ma-c0284, page 341" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "conduct drawdown analysis to ensure the design volume from impervious area will infiltrate over 3-days based on Step 3 \"Drawdown within 72 Hours\".", "page_or_section": "Chapter 6 / springfield-ma-c0151, page 187" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "It must be designed to fully dewater within 72-hours of a storm.", "page_or_section": "Appendix A Sediment Forebay / springfield-ma-c0246, page 297" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance from bottom of SCM to SHGW 2-ft", "page_or_section": "Table 2.5 / springfield-ma-c0039, page 69" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Grass channels and dry water quality swales must be at least 2 feet above seasonal high groundwater.", "page_or_section": "Table 2-4d / springfield-ma-c0017, page 47" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The depth of the soil media must be between 2 to 4 feet.", "page_or_section": "Appendix A Bioretention / springfield-ma-c0258, page 311" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum acceptable final soil infiltration rate is 0.01 inches per hour.", "page_or_section": "Appendix A Infiltration Basin / springfield-ma-c0322, page 381" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water levels in the extended detention wetlands may increase by as much as three feet after a storm, and return gradually to normal within 24 hours of the rain event.", "page_or_section": "Appendix A Extended Detention Wetlands / springfield-ma-c0270, page 325" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable standalone city design-manual PDF; MassDEP handbook is chaptered — used municipal mirror of 2023 draft with appendices (same source as ma-state-draft).", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.ashlandmass.com/DocumentCenter/View/13272/MassDEP-Handbook_DRAFT-6_2023-12-14_withAppendices-2", "landing_page_url": "https://www.mass.gov/guides/massachusetts-stormwater-handbook-and-stormwater-standards", "retrieved_at": "2026-08-10T09:45:18.900Z", "original_filename": "springfield-ma.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:14:12.035Z", "enrich_model": "composer-2.5:run-1b4480e4-3145-4a37-8ed4-35bdfa8e5175", "enrich_notes": "WQv is 1.0 inch × post-development impervious area (MassDEP). Recharge/infiltration SCMs must demonstrate drawdown within 72 hours; mounding analysis required when SHGW separation ≤4 ft and exfiltrating ≥10-year storm volume. Table 2.5: 2-ft minimum from bottom of SCM to seasonal high groundwater (SHGW) for most infiltration and many treatment SCMs; grass channels and dry water quality swales also ≥2 ft above SHGW. Bioretention filter media 2–4 ft deep (30 in minimum if nitrogen TMDL; 3 ft if trees/shrubs). Porous pavement: ≥2 ft to SHGW/bedrock; slopes generally ≤5%; open-graded subbase ≥40% voids (no explicit storage depth in inches). Minimum acceptable final soil infiltration rate for infiltration basins: 0.01 in/hr. Extended detention wetlands may rise ~3 ft after storms and return to normal within 24 hours. Media filters sized for 1.0 inch WQV; dry designs dewater in 72 hours. 44% TSS pretreatment before infiltration SCMs (cold-water fisheries table). Springfield follows MassDEP handbook / ma-state-draft appendix specs.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "springfield-mo", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/springfield-mo/", "data_url": "https://stormwateratlas.com/data/manuals/springfield-mo.json", "document_metadata": { "jurisdiction_name": "City of Springfield", "jurisdiction_level": "municipality", "state_code": "MO", "document_title": "Flood Control and Water Quality Protection Manual", "version_or_edition": "April 2022 (effective May 4, 2022)", "adoption_or_effective_date": "2022-05-04", "last_revised_date": "2022-04-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Chapter 10 Water Quality sets post-construction BMP requirements for new development and redevelopment. Flood control detention and conveyance design use multi-frequency storms (including 100-year system capacity / street criteria; on-site detention to prevent increases for 1-, 10-, and 100-year peaks).", "peak_flow_calculation_method": [ "100-year design storm for major drainage / easement containment", "2-, 25-, and 100-year design flows for streets (Chapter 6)", "On-site detention for 1-, 10-, and 100-year peaks", "Structural BMPs including detention (Chapter 9 / 10)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stormwater detention facilities", "Post-construction water quality BMPs", "Street / inlet / storm drain conveyance", "Sinkhole protection measures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "A Stormwater Design Guide for Development in Springfield", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Flood Control and Water Quality Protection Manual", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Adopted April 2022 / effective May 4, 2022", "page_or_section": "Cover / city notice" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "City Flood Control and Water Quality Protection Manual", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-, 25-, and 100-year design flows / 1-, 10-, and 100-year storms", "page_or_section": "Streets / Detention" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Chapter 10, Water Quality", "page_or_section": "TOC / intro" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "100-year (1 percent AEP) rainfall / on-site detention", "page_or_section": "Drainage principles / detention" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "stormwater detention / Best Management Practices (BMPs)", "page_or_section": "Introduction" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Therefore, the WQV is based on the runoff from a 1 inch rainfall.", "page_or_section": "Chapter 10, Section 2.1 Water Quality Volume, page 290" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Redevelopment projects where the previous development was not required to meet the water quality requirement shall meet a reduced WQV based on the runoff from a 0.5-inch rainfall", "page_or_section": "Chapter 10, page 288" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The required drain time for bioretention is 12-72 hours.", "page_or_section": "Chapter 10, Section 13.3.5, page 335" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "tf = maximum drain time (days) (use 3 days for the 72-hour max drain time requirement)", "page_or_section": "Chapter 10, Section 13.3.3, page 334" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bioretention storage should be located at least two feet above the seasonal high level of the water table.", "page_or_section": "Chapter 10, Section 13.3.1, page 333" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Pervious pavement storage should be located at least two feet above the seasonal high level of the water table.", "page_or_section": "Chapter 10, Section 10.4, page 319" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The bioretention soil mix filter bed thickness (df) shall be a minimum of 24 inches for pollutant removal and plant health in bioretention with an underdrain. The bioretention soil mix filter bed thickness (df) shall be a minimum of 12 inches for bioretention without an underdrain.", "page_or_section": "Chapter 10, Section 13.3.4, page 334" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The preferred ponding depth is 12 inches and the maximum allowed is 18 inches.", "page_or_section": "Chapter 10, Section 13.3.3, page 334" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The thickness of the rock storage shall be a minimum of 6 inches when no underdrain is used and 9 inches when an underdrain is used.", "page_or_section": "Chapter 10, Section 10.3, page 319" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "underdrains shall be provided if the existing subgrade infiltration rate is less than 0.5 inches/hour", "page_or_section": "Chapter 10, Section 10.4, page 319" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "In-service pervious pavement shall have a minimum infiltration rate of 10 inches/hour", "page_or_section": "Chapter 10, Section 10.3, page 319" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "To minimize the potential of algae growth, a minimum permanent pool depth of 6 feet must be provided.", "page_or_section": "Chapter 10, Section 15.3, page 350" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "designing a functional outlet to release the WQV over a 24-hour drain time is practically impossible", "page_or_section": "Chapter 10, Section 5.1.4, page 296" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The basin length to width ratio should be between 2:1 and 4:1. The minimum allowable ratio is 1:1.", "page_or_section": "Chapter 10, Section 16.4, page 356" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Design the outlet works to release the WQV in 22 to 28 hours.", "page_or_section": "Chapter 10, Section 16.4, page 356" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Pollutant removal efficiency of the system shall be certified by an independent certification program including but not limited to: U.S. EPA Technology Verification Program, State of Washington Technology Assessment Protocol - Ecology (TAPE), the Technology Acceptance Reciprocity Partnership Protocol (TARP), New Jersey Corporation for Advance Technology (NJCAT) or the State of Maryland Proprietary Practice acceptance program.", "page_or_section": "Chapter 10, Section 19.4, page 368" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Springfield FCWQP Manual April 2022. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.springfieldmo.gov/DocumentCenter/View/57515/Flood-Control-and-Water-Quality-Protection-Manual-April-2022", "landing_page_url": "https://www.springfieldmo.gov/2120/Design-Resources", "retrieved_at": "2026-08-10T09:06:14.926Z", "original_filename": "springfield-mo.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": 6, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 72, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": 22, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "U.S. EPA Technology Verification Program; TAPE; TARP; NJCAT; Maryland Proprietary Practice acceptance program", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:14:59.712Z", "enrich_model": "composer-2.5:run-6ee04ecd-bcca-4ac4-9ed5-ba3abac57a80", "enrich_notes": "WQV uses 1-inch rainfall for new development; redevelopment may use 0.5-inch on redeveloped impervious area. Bioretention filter media minimum is 24 inches with underdrain. Rock storage minimum is 9 inches when underdrain is used. In-service pervious pavement minimum infiltration is 10 in/hr. Extended wet detention WQV drain time is approximately 12–15 hours. Constructed wetland WQV release is 22–28 hours; length:width recommended 2:1 to 4:1 (minimum 1:1).", "enrich_schema_version": 2, "fields_not_found": [ "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "st-louis-mo", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/st-louis-mo/", "data_url": "https://stormwateratlas.com/data/manuals/st-louis-mo.json", "document_metadata": { "jurisdiction_name": "City of St. Louis / Metropolitan St. Louis Sewer District", "jurisdiction_level": "municipality", "state_code": "MO", "document_title": "Site Design Guidance (MSD post-construction BMP requirements / Maryland SWM Manual)", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 100 ], "water_quality_volume_method": "MSD Rules & Regulations require BMPs to treat a water quality volume based on runoff from 1.14 inches of rainfall. Structural BMP design methodology adopts Chapters 3 and 5 of the Maryland Stormwater Design Manual (2000). Flood detention: release rates not to exceed allowable 2-year and 100-year 24-hour events (NRCS TR-55).", "peak_flow_calculation_method": [ "NRCS TR-55 Urban Hydrology for Small Watersheds", "2-year and 100-year 24-hour flood detention release rates", "Maryland SWM Manual BMP sizing (Ch.3/5)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Permeable pavement", "Stormwater ponds / wetlands", "Infiltration BMPs", "Filtering systems / sand filters", "Open channel systems", "Green roof / rainwater harvesting (WQv reduction credits)" ] }, "evidence": [ { "field": "design_criteria.water_quality_volume_method", "excerpt": "MSD rules and regulations require use of BMPs to treat a water quality volume of runoff from 1.14 inches", "page_or_section": "Site Design Guidance / MSD Phase II" }, { "field": "document_metadata.document_title", "excerpt": "MSD relies upon Chapters 3 and 4 of the Maryland Department of the Environment’s (MDE), April 2000, Stormwater Design Manual", "page_or_section": "Site Design Guidance" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "MSD rules and regulations require the use of BMPs to treat a water quality volume of runoff from 1.14 inches of rainfall.", "page_or_section": "page 14, Table 3 / Post-Construction Structural BMPs" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention", "page_or_section": "page 14, Table 3 Stormwater Filtering System" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Permeable Pavement", "page_or_section": "page 14, Table 3 Alternative Surface Materials" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roof", "page_or_section": "page 14, Table 3 Alternative Surface Materials" }, { "field": "practice_mentions.swale", "excerpt": "Dry Swale • Wet Swale", "page_or_section": "page 14, Table 3 Open Channel Systems" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Hydrodynamic Separator Devices • MSD Approved Devices", "page_or_section": "page 14, Table 3" }, { "field": "practice_mentions.extended_detention", "excerpt": "Micropool Extended-Detention (ED) Ponds ... Wet ED Ponds ... ED Shallow Wetland", "page_or_section": "page 14, Table 3" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Criteria from Phase II Site Design Guidance documenting MSD rules; prefer direct MSD Laserfiche design chapter when available.", "fields_not_found": [] }, "source": { "document_url": "https://www.rockhillmo.net/sites/g/files/vyhlif1136/f/uploads/site_design_guidance.pdf", "landing_page_url": "https://msdprojectclear.org/what-we-do/stormwater-management/bmp-toolbox/technology-matrix/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "st-louis-mo.pdf" }, "design_parameters": { "wqv_depth_inches": 1.14, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:15:22.919Z", "enrich_model": "composer-2.5:run-991f19f2-5139-44ad-b4c9-0c6465c3099d", "enrich_notes": "MSD requires BMPs to treat WQv from 1.14 in rainfall; structural BMP design defers to Maryland Stormwater Design Manual (2000) Ch. 3–4. WQv also defined as storage for 90th-percentile daily rainfall per MSD Rules 4.080.02. Infiltration basin DA ≤10 ac, trench ≤5 ac; open-channel/swale BMPs ≤5 ac DA; ponds ≥10 ac; wetlands ≥25 ac. Channel protection: extended detention for 1-year 24-hour event. Example appendix shows WQv in cu ft only, not depth.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "stamford-ct", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/stamford-ct/", "data_url": "https://stormwateratlas.com/data/manuals/stamford-ct.json", "document_metadata": { "jurisdiction_name": "City of Stamford", "jurisdiction_level": "municipality", "state_code": "CT", "document_title": "Connecticut Stormwater Quality Manual (city follows CT DEEP 2024 Manual)", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-03-30", "last_revised_date": "2024-03-26", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV = (P)(R)(A)/12 where P = 1.3 inches (90th percentile rainfall event), R = volumetric runoff coefficient = 0.05 + 0.009(I).", "peak_flow_calculation_method": [ "NRCS Curve Number method", "Graphical Peak Discharge Method", "TR-20", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "WinTR-55", "HydroCAD", "TR-20" ], "approved_bmp_categories": [ "Pretreatment BMPs", "Infiltration BMPs", "Filtering BMPs", "Stormwater Pond BMPs", "Stormwater Wetland BMPs", "Water Quality Conveyance BMPs", "Stormwater Reuse BMPs", "Proprietary BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Stamford follows CT Stormwater Quality Manual 2024", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — CT DEEP 2024 Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "𝑊𝑊𝑊𝑊𝑊𝑊 = (𝑃𝑃)(𝑅𝑅)(𝐴𝐴) 12 where: WQV = water quality volume (cubic feet) P = 1.3 inches (90th percentile rainfall event) R = volumetric runoff coefficient = 0.05+0.009( I) I = post- development impervious area (percent) after application of non-structural LID site p", "page_or_section": "p. 53" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.3 inches (90th percentile rainfall event)", "page_or_section": "Chapter 4, page 53" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention system should completely drain in 48 hours or less after the end of the design storm", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration system ... should be located at least 3 feet above the SHGT and bedrock", "page_or_section": "Chapter 10, page 194" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered bioretention soil media should have a depth of 24 to 48 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for water quality storm: 12 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "0.5 inches per hour (1.0 feet per day) for the bioretention soil media, whichever value is lower", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention basin should completely drain within 48 hours after the end of a storm", "page_or_section": "Chapter 13 – Dry Extended Detention Basin, page 467" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width Minimum: 2 feet", "page_or_section": "Chapter 13 – Wet Water Quality Swale, page 421" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green Roof ... (max 20% roof slope)", "page_or_section": "Chapter 8 Table 8-3, page 140" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via CT Stormwater Quality Manual 2024 (same pattern as other CT cities without local manuals).", "fields_not_found": [] }, "source": { "document_url": "https://portal.ct.gov/-/media/deep/water/water_quality_management/guidance/swm_mar_2024.pdf", "landing_page_url": "https://portal.ct.gov/DEEP/Water-Regulating-and-Discharges/Stormwater/Stormwater-Manual", "retrieved_at": "2026-08-10T09:45:18.921Z", "original_filename": "stamford-ct.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 20, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:15:59.697Z", "enrich_model": "composer-2.5:run-96ddf50e-b742-48e3-a73c-f24cf9cf8aa1", "enrich_notes": "Stamford follows CT DEEP 2024 Manual; WQV uses P=1.3 in and R=0.05+0.009(I). SHGT separation: 36 in (3 ft) recommended for infiltration bottoms; filtering systems may use 12 in (1 ft) above SHGT per Table 8-5 note. Bioretention trees require min 30 in soil depth. QPA requires ≥18 in depth to SHGT. Infiltration suitability threshold 0.3 in/hr; high-rate soils >8.3 in/hr need pretreatment.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "stockton-ca", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/stockton-ca/", "data_url": "https://stormwateratlas.com/data/manuals/stockton-ca.json", "document_metadata": { "jurisdiction_name": "City of Stockton / San Joaquin County", "jurisdiction_level": "special_district", "state_code": "CA", "document_title": "Stormwater Quality Control Criteria Plan (SWQCCP)", "version_or_edition": "March 2025", "adoption_or_effective_date": "2025-03", "last_revised_date": "2025-03", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Priority Projects must meet Volume Reduction Requirement (VRR): reduce post-project runoff to at or below pre-project volumes for the 0.51-inch storm depth (average 85th percentile). VRR is independent of Stormwater Quality Design Volume (SQDV) / Stormwater Quality Design Flow (SQDF). Also apply site design, source, volume reduction, and treatment controls (bioretention, infiltration, extended detention, etc.).", "peak_flow_calculation_method": [ "Volume Reduction Requirement hydrology (pre vs post for 0.51-inch storm)", "SQDV / SQDF treatment sizing (Appendix T-0)", "LID treatment control design worksheets" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Site design controls", "Source controls", "Volume reduction measures (VRMs)", "Bioretention", "Infiltration basin / trench", "Extended detention basin", "Treatment controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Agreement and Forms D-1: City of Stockton Stormwater Treatment Device Access and Maintenance Agreement Template D-2: Placeholder [Not in Use] D-3: SWQCP Owner’s Certification Statement D-4: County of San Joaquin Stormwater Treatment Device Access and Maintenance Agreement", "page_or_section": "p. 4" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Stockton and San Joaquin County", "page_or_section": "FAQ / applicability" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Quality Control Criteria Plan", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Regionwide Permit / Statewide Trash Amendments", "page_or_section": "Background" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "project runoff volumes for the 0.51-inch storm depth, which is the average 85th", "page_or_section": "Section 5.2 VRR" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "VRR is a separate and independent requirement from the Stormwater Quality Design Volume (SQDV)", "page_or_section": "Section 5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention / Infiltration Basin / Extended Detention Basin", "page_or_section": "Chapter 6 fact sheets" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "post-project runoff volumes be reduced to match pre-project levels for the 0.51-inch storm depth, the average 85th percentile/24-hour storm depth estimated for the Stockton area", "page_or_section": "5.2 Volume Reduction Requirement / page 52 (stockton-ca-c0076)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom Basin Elevation ft 10 ft above seasonally high groundwater table minimum.", "page_or_section": "Table 6-17 Infiltration Basin / page 118 (stockton-ca-c0135)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Minimum groundwater separation 10 ft Between trench bottom and seasonally high groundwater table", "page_or_section": "Table 6-19 Infiltration Trench / page 125 (stockton-ca-c0141)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth to seasonal high groundwater level should be at least 10 feet from the bottom of the structure.", "page_or_section": "Table 6-8 Bioretention / page 96 (stockton-ca-c0116)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of planting media 18 - 24 inches", "page_or_section": "Table 6-8 Bioretention Design Criteria / page 96 (stockton-ca-c0116)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum depth of ponding zone (DPZ) 12 inches Depth above top much layer", "page_or_section": "Table 6-8 Bioretention Design Criteria / page 96 (stockton-ca-c0116)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention Basin (C-2) SQDV 48 hours", "page_or_section": "Table 6-4 Sizing Criteria for Treatment Controls / page 88 (stockton-ca-c0109)" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Constructed Wetland (C-1) SQDV 24 hours", "page_or_section": "Table 6-4 Sizing Criteria for Treatment Controls / page 88 (stockton-ca-c0109)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Pond length to width ratio 2:1 Minimum (larger preferred)", "page_or_section": "Table 6-39 Wet Pond Design Criteria / page 186 (stockton-ca-c0183)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Joint Stockton/SJC SWQCCP March 2025 FULL FINAL. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.sjwater.org/Portals/0/ThemePluginPro/uploads/2025/7/1/FULL%20FINAL%20SWQCCP%20Stockton%20SJC%20March%202025_1.pdf", "landing_page_url": "https://www.sjwater.org/Stormwater-Management/Development", "retrieved_at": "2026-08-10T08:24:40.117Z", "original_filename": "stockton-ca.pdf" }, "design_parameters": { "wqv_depth_inches": 0.51, "max_drawdown_hours": null, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:16:22.539Z", "enrich_model": "composer-2.5:run-f8ece916-d94f-472a-969e-69b9d4fc4361", "enrich_notes": "VRR is tied to 0.51-inch storm depth (85th percentile, Stockton); SQDV/SQDF sizing is separate (Fact Sheet T-0). Drawdown periods vary by BMP (Table 6-4): e.g. bioretention 12 h, wetland 24 h, infiltration basin/trench and extended detention 48 h. Infiltration basin/trench cite soil permeability design range 0.6–2 in/hr (saturated vertical); Table 6-3 gives typical infiltration rates by USDA soil type A–D. Ten-foot minimum separation from seasonally high groundwater appears for infiltration basin bottom, infiltration trench bottom, and bioretention (depth to groundwater >10 ft from structure bottom). Wet pond lists littoral depth 6–18 in, deeper zone 4–8 ft average and 12 ft maximum, forebay 2–4 ft—not mapped to a single permanent_pool_depth_inches.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "syracuse-ny", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/syracuse-ny/", "data_url": "https://stormwateratlas.com/data/manuals/syracuse-ny.json", "document_metadata": { "jurisdiction_name": "City of Syracuse", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "New York State Stormwater Management Design Manual (adopted; applies in Syracuse)", "version_or_edition": "July 31, 2024", "adoption_or_effective_date": "2024-07-31", "last_revised_date": "2024-07-31", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "USDA NRCS TR20", "HydroCAD", "Pond Pack", "StormCAD", "Hydraflow", "HEC-HMS" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Practices", "Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Syracuse Stormwater Management Reviews cite NYS Design Manual", "page_or_section": "Coverage note / syr.gov Engineering" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT DESIGN MANUAL", "page_or_section": "Title Page" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) 90% Rule: WQv (acre-feet) = (P ∙ Rv ∙ A) / 12 Rv = 0.05+0.009(I) I = Impervious Cover (Percent) P(inches) = 90% Rainfall Event Number (See Figure 4.1) 2 A = Contributing Area (acres) Runoff Reduction Volume (RRv) RRv (acre-feet) = Reduction of", "page_or_section": "p. 43" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "urban stormwater runoff 2. To provide design standards on the most effective stormwater management approaches including: o Incorporation of runoff reduction achieved by infiltration, groundwater recharge, reuse, recycle, evaporation/evapotranspiration through the use of runoff", "page_or_section": "p. 11" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "90th percentile rainfall 1.20 inches (Section 4.2)", "page_or_section": "Chapter 7, Table 7.1" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min 2 ft separation to seasonal high-water table or bedrock", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of filter media shall be 30 inches min and 48 inches max", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max ponding is 12 inches (WQv) and 18 inches (Extreme Flood)", "page_or_section": "Fact Sheet: Filtration Bioretention (F-5), Chapter 6" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underlying soils shall have an min. infiltration rate of 0.50 inch/hr", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), Chapter 6" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size outlet structure to detain WQv for 24 hrs (12 hrs to trout waters)", "page_or_section": "Fact Sheet: Wet Pond (P-2), Chapter 6" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Min. flow path of 1.5:1 (length to relative width) from all inlet points to the outflow points across the pond", "page_or_section": "Fact Sheet: Wet Pond (P-2), Chapter 6" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be a min of 2 ft and a max of 8 ft", "page_or_section": "Fact Sheet: Dry Swale (O-1), Chapter 6" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide a 2' separation distance to water table.", "page_or_section": "Table 3.5 Watershed/Regional Selection Matrix, Chapter 3" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum ponding depth shall be 12 inches during the WQv event", "page_or_section": "Fact Sheet: Rain Garden (RR-6), Chapter 5" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NYS Stormwater Management Design Manual (same pattern as Rochester/Yonkers). City also has Ordinance #53.", "fields_not_found": [] }, "source": { "document_url": "https://extapps.dec.ny.gov/fs/projects/24-25DraftCGPDesignManual/Manual.SW.CGP.2024-07-31.Design_Manual_Issued_2024-07-31.pdf", "landing_page_url": "https://www.syr.gov/Departments/Engineering/Stormwater-Management-Reviews", "retrieved_at": "2026-08-10T09:39:14.782Z", "original_filename": "syracuse-ny.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:17:11.884Z", "enrich_model": "composer-2.5:run-f9f6e3a9-d0c9-4a28-9215-b1016b55643f", "enrich_notes": "NYS manual (Syracuse): WQv uses 90th-percentile P (example 1.20 in); RRv must reduce 100% of WQv before remaining WQv to standard SMPs. Infiltration infeasible when soils < 0.5 in/hr. Rain gardens (RR-6) use 12–18 in filter media min vs 30 in min for F-4/F-5 bioretention. Pond outlet: detain WQv 24 h (12 h trout waters). Sole-source aquifer often requires 4 ft SHWT separation vs 2 ft default.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tacoma-wa", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tacoma-wa/", "data_url": "https://stormwateratlas.com/data/manuals/tacoma-wa.json", "document_metadata": { "jurisdiction_name": "City of Tacoma", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Stormwater Management Manual", "version_or_edition": "July 2016 Edition", "adoption_or_effective_date": null, "last_revised_date": "2016-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Minimum Requirement #6: Water Quality Treatment. Onsite stormwater management, flow control, and water quality treatment volumes/facilities per SWMM Minimum Requirements for new development and redevelopment.", "peak_flow_calculation_method": [ "Minimum Requirements for New Development and Redevelopment (Chapter 3)", "Flow control and conveyance design (Volume 3)", "Infiltration facilities and detention for flow control" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Onsite stormwater management BMPs", "Water quality treatment facilities", "Flow control / detention facilities", "Infiltration facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Tacoma Environmental Services", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Tacoma", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "--- page 5 --- City of Tacoma July 2016 SWMM P-2 Table of Contents 3.4.3 Minimum Requirement #3: Source Control of Pollution . . . . . . . . . . . . . . . . . . . 1-33 3.4.4 Minimum Requirement #4: Preservation of Natural Drainage Systems and Outfalls . . . . . .", "page_or_section": "p. 5" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "July 2016 Edition", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Surface Water Management Manual", "page_or_section": "Notice" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Flow Control & Conveyance", "page_or_section": "Volume 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Minimum Requirement #6: Water Quality Treatment", "page_or_section": "Section 3.4.6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Minimum Requirements for New Development and Redevelopment", "page_or_section": "Chapter 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Facilities / Detention", "page_or_section": "Volume 3" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Document that the water quality design storm volume (indicated by WWHM) can infiltrate through the infiltration basin surface within 48 hours.", "page_or_section": "Volume 5, Section 7.6.4.2 Drawdown Time" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of one foot of separation is required from the bottom of the drywell to the seasonal high groundwater table.", "page_or_section": "Volume 3, BMP L602.b, Section 2.3.3.5" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of one foot of separation is required between the lowest elevation of the rain garden soil or any underlying gravel infiltration layer and the seasonal high groundwater elevation or other impermeable layer.", "page_or_section": "Volume 6, Section 2.2.2.1.2.2 Groundwater Separation" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Design (long-term) infiltration rates up to 3 inches/hour can be considered if the infiltration receptor is not a sole-source aquifer", "page_or_section": "Volume 5, Section 7.6.4.1 Infiltration Rates" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "if the measured infiltration rate is at least 8 inches per hour.", "page_or_section": "Volume 3, Section 2.5.3 Design Criteria (perforated stub-outs in fill)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Tacoma SWMM July 2016; text truncated but Minimum Requirements structure clear. Newer editions may exist. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://cms.cityoftacoma.org/enviro/SurfaceWater/2016%20SWMM%20Manual/SWMM%20July%202016%20Masterbook.pdf", "landing_page_url": "https://www.cityoftacoma.org/government/city_departments/environmentalservices/surface_water", "retrieved_at": "2026-08-10T08:08:51.648Z", "original_filename": "tacoma-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 3, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:17:57.596Z", "enrich_model": "composer-2.5:run-27e7aa1f-e354-4602-b58d-ec3706f18dab", "enrich_notes": "SHWT separation varies by BMP: 12 in (1 ft) rain gardens, drywells, small bioretention, L604 trenches; 36 in (3 ft) larger bioretention; 60 in (5 ft) base of infiltration basins/trenches with possible 36 in alternative. Design infiltration: long-term up to 3 in/hr for treatment; measured initial ≤9 in/hr; fill stub-outs require ≥8 in/hr measured; rain garden infeasibility if native Ksat <0.30 in/hr. Bioretention swale ponding typically 6–12 in (range, not single design minimum). WQ volume sizing referenced via WWHM, no inch depth in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tallahassee-fl", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tallahassee-fl/", "data_url": "https://stormwateratlas.com/data/manuals/tallahassee-fl.json", "document_metadata": { "jurisdiction_name": "City of Tallahassee (NWFWMD criteria)", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "NWFWMD Environmental Resource Permit Applicant’s Handbook Volume II (design standards)", "version_or_edition": "June 28, 2024", "adoption_or_effective_date": "2024-06-28", "last_revised_date": "2024-06-28", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "NWFWMD ERP AH Vol II stormwater quality criteria (Parts II/IV/V) including retention system treatment volume and additional quality standards. Quantity/flood criteria include 10-year floodplain storage and 100-year floodway conveyance limits.", "peak_flow_calculation_method": [ "Stormwater quantity rate and volume controls (Part III)", "Retention / detention routing", "Floodplain / floodway conveyance checks" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems", "Detention systems", "On-line and off-line stormwater systems", "Stormwater quantity / flood control facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Tallahassee capital / NWFWMD geographic boundaries", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "municipality — City of Tallahassee", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "Northwest Florida Water Management District", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT’S HANDBOOK VOLUME II", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Chapter 62-330, F.A.C. ERP stormwater design", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design Criteria and Guidelines for Retention Systems ... Treatment Volume", "page_or_section": "Part V §5.0" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Stormwater Quantity: Rate and Volume Controls", "page_or_section": "Part III" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Systems; On-Line and Off-line Stormwater Systems", "page_or_section": "TOC" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-year floodplain ... 100-year flood elevation", "page_or_section": "§3.4" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The retention system must provide the capacity for the appropriate treatment volume of stormwater specified in Section 5.2 of this Volume within 72 hours following a storm event", "page_or_section": "5.0.3 Recovery Time" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The system shall be designed to recover the required treatment volume of stormwater runoff within 72 hours following a storm event assuming average antecedent moisture conditions.", "page_or_section": "5.1.3 Recovery Time" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The exfiltration trench system shall be designed so that the invert elevation of the trench is at least two feet above the seasonal high ground water table elevation", "page_or_section": "5.1.8 Ground Water Table" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The average length to width ratio of the pond must be at least 2:1.", "page_or_section": "5.2.8 Pond Configuration" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipal map coverage via NWFWMD ERP AH Vol II. Canonical special_district record: fl-nwfwmd-erp-ah2. Capital coverage via NWFWMD ERP AH Vol II (regional design criteria). City operating-permit checklists not separately ingested.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://nwfwater.com/wp-content/uploads/2024/07/AHII-nwfwmd-FINAL-2024.pdf", "landing_page_url": "https://nwfwater.com/", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "tallahassee-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:18:56.770Z", "enrich_model": "composer-2.5:run-4f3460c6-ebdc-4a08-8551-b9ef40332a87", "enrich_notes": "Treatment volume sizing references NWFWMD ERP Vol I Sections 8.3 and 9 (nutrient performance), not a fixed inch WQv depth in these excerpts. Retention and exfiltration share 72-hour recovery at average AMC; exfiltration optional safety factor includes 36-hour drawdown design. Wet detention requires half of treatment volume drawdown in 48–60 hours and minimum L:W 2:1; max pond depth 12 ft. Exfiltration trench invert minimum 2 ft above seasonal high groundwater (24 in). Swales sized for 3-year, 1-hour storm infiltration on HSG A/B; cross-section top width:depth ≥6:1. Appendix B-2 cites detention-with-filtration checklist (FDM 1988), not a standalone sand filter depth standard in Part V.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tampa-fl", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tampa-fl/", "data_url": "https://stormwateratlas.com/data/manuals/tampa-fl.json", "document_metadata": { "jurisdiction_name": "City of Tampa (SWFWMD criteria)", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II — Design Requirements for Stormwater Treatment and Management Systems: Water Quality and Water Quantity", "version_or_edition": "Effective June 1, 2018 (draft text with NEW DATE markers)", "adoption_or_effective_date": "2018-06-01", "last_revised_date": "2018-06-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "District Vol. II criteria work with statewide ERP Applicant's Handbook Volume I performance standards: wet detention sized for one inch of runoff from the contributing area; retention, effluent filtration, or exfiltration sized for one-half inch of runoff (or, for several BMP types, treat runoff from the first one inch of rainfall, with an option for drainage areas under 100 acres of the first one-half inch of runoff). Treatment volume must again be available within 72 hours (only the portion recoverable in 36 hours may count toward quantity storage). Direct OFW discharges require 50% more treatment volume than the selected system.", "peak_flow_calculation_method": [ "Historic peak discharge or legally allowable discharge (open basins)", "NRCS Type II Florida Modified 24-hour rainfall distribution with AMC II on SWFWMD 24-hour/25-year (open) or 24-hour/100-year (closed) rainfall maps", "Soil Conservation Service / NRCS National Engineering Handbook Section 4 hydrology methods", "Rainfall minus losses and storage", "Rational method (projects less than 10 acres total contributing area)", "USDA-SCS TR-55 Urban Hydrology for Small Watersheds / Technical Paper No. 149 (infiltration)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Detention with effluent filtration (manmade underdrains)", "On-line retention treatment systems", "Off-line retention treatment systems", "Underground exfiltration treatment systems", "Dry grassed swales / sediment-oil-grease pretreatment", "Sensitive karst area stormwater systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "FOR USE WITHIN THE GEOGRAPHIC LIMITS OF THE SOUTHWEST FLORIDA WATER MANAGEMENT DISTRICT", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This Volume II ... is intended for use only within the jurisdictional boundaries of the Southwest Florida Water Management District.", "page_or_section": "Section 1.0 Introduction" }, { "field": "document_metadata.state_code", "excerpt": "administration of Chapter 62-330, Florida Administrative Code (F.A.C.).", "page_or_section": "Section 1.0 Introduction" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II DESIGN REQUIREMENTS FOR STORMWATER TREATMENT AND MANAGEMENT SYSTEMS WATER QUALITY AND WATER QUANTITY", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "EFFECTIVE June 1, 2018NEW DATE", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE June 1, 2018", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "EFFECTIVE June 1, 2018", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Each Water Management District has adopted an ERP Applicant's Handbook Volume II ... District-specific design and performance criteria for stormwater quantity or, flood control systems, design criteria for stormwater quality systems", "page_or_section": "Section 1.0 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "off-site discharges and peak stages for the existing and developed conditions shall be computed using the Southwest Florida Water Management District's 24-hour, 25-year rainfall maps and the Natural Resources Conservation Service type II Florida Modified 24-hour rainfall distribution", "page_or_section": "Section 3.1 Discharges" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the required retention volume shall be the post-development runoff volume less the pre-development runoff volume computed using the Southwest Florida Water Management District's 24-hour/100-year rainfall map", "page_or_section": "Section 3.1 Discharges (closed basin)" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the proposed stormwater management system shall not be required to account for storm events less frequent than the 25-year event for the rate of discharge in an open basin or the 100-year event for the volume of discharge in a closed basin.", "page_or_section": "Section 3.1.e" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required water quality system must have treatment capacity for one inch of runoff if wet detention is used, or one-half inch of runoff if retention, effluent filtration or exfiltration is used, from the total developed site and contributing offsite area.", "page_or_section": "Section 3.5 / water quality capacity" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "A wet detention treatment system shall be designed to meet the stormwater quality treatment criteria specified in Part II of Volume I.treat one inch of runoff from the contributing area.", "page_or_section": "Section 4.1.a Wet Detention Systems" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat the runoff from the first one inch of rainfall; or as an option for projects or project subunits with drainage areas less than 100 acres, the first one-half inch of runoff.", "page_or_section": "Section 4.1.b Detention with Effluent Filtration" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Projects discharging directly into Outstanding Florida Waters (OFW) shall be required to provide treatment for a volume 50 percent more than required for the selected treatment system", "page_or_section": "Section 4.1.f" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Total treatment volume shall again be available within 72 hours, however, only that volume which can again be available within 36 hours may be counted as part of the volume required for water quantity storage", "page_or_section": "Section 4.1.c On-line Retention" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "historic discharge, which is the peak rate at which runoff leaves a parcel of land by gravity under existing site conditions, or the legally allowable discharge at the time of permit application", "page_or_section": "Section 3.1.a" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Natural Resource Conservation Service Type II Florida Modified rainfall distribution will be used unless the applicant demonstrates that a different distribution better characterizes the actual rainfall distribution", "page_or_section": "Section 6.3 Rainfall Distribution" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Soil Conservation Service design methods (see, for example, U.S. Department of Agriculture, Soil Conservation Service, \"National Engineering Handbook, Section 4, Hydrology.\"", "page_or_section": "Section 6.7 Runoff" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational method, for systems serving projects of less than 10 acres total contributing area.", "page_or_section": "Section 6.7.c" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "a. Wet Detention Systems ... b. Detention with Effluent Filtration System (Manmade Underdrains) ... c. On-line Treatment Systems ... d. Off-line Treatment Systems ... e. Underground Exfiltration Systems", "page_or_section": "Part IV Table of Contents / Section 4.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Normally, a dry grassed swale system designed for detention of the first one-fourth inch of runoff with an overall depth of no more than 4 inches will satisfy the requirement for prior removal of sediment, oils and greases.", "page_or_section": "Section 4.1.a.3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Especially iIn sensitive karst areas, stormwater management systems must be designed and", "page_or_section": "Section 5.10 Sensitive Karst Areas" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the center line of the perforated pipe", "page_or_section": "4.1.b.2 / page 25" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the bottom of the exfiltration pipe.", "page_or_section": "4.1.e.3 / page 27" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treat one inch of runoff from the contributing area", "page_or_section": "4.1.a.1 / page 24" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "one inch of runoff if wet detention is used, or one-half inch of runoff if retention, effluent filtration or exfiltration is used", "page_or_section": "Section 3.5.a / page 22" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Total treatment volume shall again be available within 72 hours", "page_or_section": "4.1.c.2 / page 26" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The total detention volume shall again be available within 36 hours.", "page_or_section": "4.1.b.4 / page 26" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Credit for the PPV is limited to a maximum depth of 8 feet", "page_or_section": "4.1.a.3 / page 24" }, { "field": "practice_mentions.swale", "excerpt": "dry grassed swale system designed for detention of the first one-fourth inch of runoff with an overall depth of no more than 4 inches", "page_or_section": "4.1.a.3(c) / page 25" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipal map coverage via SWFWMD ERP AH Vol II. Canonical special_district record: fl-swfwmd-erp-ah2. Previously mislabeled as county; reclassified to municipality proxy. Regional SWFWMD ERP Applicant's Handbook Vol II (Tampa Bay / SW Florida WMD), not a City of Tampa municipal manual. Source PDF appears draft (DRAFT/NEW DATE OCR artifacts and duplicated text). Numeric WQ depths also defer heavily to statewide AH Volume I; Vol II retains classic one-inch wet detention / half-inch retention-filtration-exfiltration sizing plus OFW +50%. Jurisdiction coded as county per task guidance.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.swfwmd.state.fl.us/sites/default/files/medias/documents/draftswfwmd-erpapplicanthandbook-volume-ii.pdf", "landing_page_url": "https://www.swfwmd.state.fl.us/business/epermitting/rules", "retrieved_at": "2026-08-08T11:46:26.214Z", "original_filename": "tampa-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:19:41.125Z", "enrich_model": "composer-2.5:run-003f6361-6447-417b-8cd8-f9176e67438a", "enrich_notes": "WQ treatment depth is explicitly one inch of runoff for wet detention and one-half inch of runoff (or first one inch of rainfall, with optional one-half inch runoff for drainage areas under 100 acres) for retention, effluent filtration, and exfiltration; no single scalar wqv_depth_inches assigned. Treatment volume recovery times vary: 36 hours (detention with effluent filtration), 72 hours (on-line/off-line retention and underground exfiltration), with only volume recoverable within 36 hours counting toward quantity storage where stated. Wet detention treatment volume must discharge over no less than 120 hours. PPV credit limited to maximum 8 feet depth below control elevation. Exfiltration design applies safety factor 2.0 to rate but no numeric design infiltration rate given.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "toledo-oh", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/toledo-oh/", "data_url": "https://stormwateratlas.com/data/manuals/toledo-oh.json", "document_metadata": { "jurisdiction_name": "City of Toledo", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Rainwater and Land Development — Ohio's Standards for Stormwater Management (city MS4)", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "WQv (ac-ft) = C × 0.75 × A / 12 (treat runoff from 0.75 inch of precipitation); Ohio EPA NPDES requires 20% additional WQv for sediment; extended detention drawdown 24–48 hours. Used where no durable city design-manual PDF was found (or prior extract was empty/scanned).", "peak_flow_calculation_method": [ "NRCS TR-55", "USGS empirical equations for small urban streams in Ohio", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water Quality Ponds", "Infiltration / Filtration practices", "LID / Conservation Development", "Wetland / Stream setbacks" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Toledo MS4 — Ohio Rainwater and Land Development standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "for construction activities. WQv (ac-ft) = C * 0.7\u0018 * A / \u00182 (Equation \u0018) Where: C = runoff coefficient A = area draining into the BMP in acres The runoff coefficient, C, is calculated using the following equation or alternatively values provided in the current Ohio EPA NP", "page_or_section": "p. 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 0.75 inch precipitation depth", "page_or_section": "CHAPTER 2 Bioretention Design Checklist, page 83" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv (ac-ft) = C * 0.75 * A / 12 (Equation 1)", "page_or_section": "CHAPTER 2 Water Quality Volume, pages 37/376" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "ds = planting soil depth (2.5 feet minimum)", "page_or_section": "CHAPTER 2 Bioretention, page 84" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil Media (generally 2.5 – 4 feet deep)", "page_or_section": "CHAPTER 2 Bioretention, page 84" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "length generally exceeding 2:1 (length:width)", "page_or_section": "CHAPTER 2 Bioretention, pages 80/84" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Ohio EPA requires that runoff treated with a bioretention practice have a minimum drawdown time of 40 hours", "page_or_section": "CHAPTER 2 Bioretention, pages 79/386" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 48-hour period (dry ED); over a 24-hour period (wet ED)", "page_or_section": "CHAPTER 2 Dry/Wet Extended Detention, pages 40–41/377–378" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum 4ft of separation required between the water table and the bioretention practice; infiltration trench: at least 2 feet between seasonal high-water table and trench bottom", "page_or_section": "CHAPTER 2 Bioretention page 77; Infiltration Trench page 51" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil infiltration rates within the trench must be between 0.52 and 2.5 inches per hour", "page_or_section": "CHAPTER 2 Infiltration Trench, page 50" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "mean depth of the permanent pool should be between 3 and 6 feet", "page_or_section": "CHAPTER 2 Wet Extended Detention, pages 41/378" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "depth of ponding should generally be less than 6 inches, but may be designed up to 12 inches", "page_or_section": "CHAPTER 2 Bioretention, page 80" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide Ohio manual used as MS4 post-construction reference when city PDF unavailable/empty.", "fields_not_found": [] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "toledo-oh.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:22:24.064Z", "enrich_model": "composer-2.5:run-a68698f1-101c-4a31-baa3-9bfb11c8c1ee", "enrich_notes": "Ohio WQv uses 0.75 in precipitation (P) in WQv = C × 0.75 × A / 12; NPDES requires +20% WQv for sediment. Extended-detention drawdown varies by pond type (dry ED 48 hr; wet/wetland ED 24 hr; general WQv drainage cited as 24–48 hr). Bioretention: Ohio EPA minimum 40 hr drawdown; planting soil ≥2.5 ft; ponding generally <6 in, up to 12 in; length:width generally >2:1; 4 ft required (2 ft recommended) separation to seasonal high groundwater. Infiltration trench: soil K 0.52–2.5 in/hr; WQv drain 24–48 hr; ≥2 ft to SHWT/bedrock at trench bottom. Sand filter: 40 hr total design drawdown. Wet pool mean depth 3–6 ft; wetland pool depths generally 6–18 in (avg 6–12 in). Corpus is statewide Ohio Rainwater and Land Development manual used as Toledo MS4 reference.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "topeka-ks", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/topeka-ks/", "data_url": "https://stormwateratlas.com/data/manuals/topeka-ks.json", "document_metadata": { "jurisdiction_name": "City of Topeka", "jurisdiction_level": "municipality", "state_code": "KS", "document_title": "Stormwater BMP Design Handbook", "version_or_edition": "January 2021", "adoption_or_effective_date": "2021-01-01", "last_revised_date": "2021-01-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Meet or exceed Level of Service (LS) using the MARC/APWA Manual of Best Management Practices for Stormwater Quality Value Rating method (Table 3-1 Overall Value Ratings). BMPs designed per Handbook + MARC/APWA specs; quantity BMPs (detention/retention) addressed in Handbook Ch. 4 with conveyance still in Design Criteria & Drafting Standards.", "peak_flow_calculation_method": [ "MARC/APWA Level of Service / Value Rating method", "Handbook Chapter 4 stormwater quantity BMP design", "City Design Criteria & Drafting Standards for linear conveyance" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Native vegetation preserved/established", "Rain garden", "Infiltration basin / trench", "Bioretention", "Pervious concrete / porous asphalt / modular block", "Extended detention wetland", "Sand filters", "Extended wet / dry detention", "Vegetated filter strip / native swale", "Manufactured treatment devices (policy)", "Cistern (Appendix F)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Topeka, Kansas", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater BMP Design Handbook", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Version: January 2021", "page_or_section": "Footer" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Applicable developments shall be designed and constructed to meet or exceed the Level of Service (LS) required for the site as evaluated using the Level of Service Method described in the most recent version of the MARC/APWA Manual", "page_or_section": "§3.3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Table 3-1. Stormwater Quality BMP Value Ratings ... Bioretention ... Infiltration Basin", "page_or_section": "Table 3-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "independent — aligns with MARC/APWA BMP Manual and TMC 13.35", "page_or_section": "§1.4 / §3.3" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "For dry detention BMPs not designed for extended detention, the design shall allow for discharge of at least 80 percent of the detention storage volume within 24 hours after the peak or center of mass of the inflow has entered the detention basin.", "page_or_section": "Chapter 4, page 4-11 (Section 7.d)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "There must be more than three (3) feet of separation distance from the bottom of the BMP to the elevation of the seasonally saturated soils or the top of bedrock.", "page_or_section": "Chapter 3, page 3-7 (Policy 3.a.iv)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The minimum normal depth of water before the introduction of excess stormwater shall be four feet plus a sedimentation allowance of not less than 5 years accumulation.", "page_or_section": "Chapter 4, page 4-12 (Section 4.3.2.1.b)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "LS/Value Rating method rather than fixed rainfall depth WQv; quantity design storms live partly in companion Design Criteria manual.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://cot-wp-uploads.s3.amazonaws.com/wp-content/uploads/utilities/stormwater/Topeka+SW+Design+Handbook.pdf", "landing_page_url": "https://www.topeka.gov/utilities/stormwater/index.php", "retrieved_at": "2026-08-10T09:39:14.769Z", "original_filename": "topeka-ks.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:22:50.612Z", "enrich_model": "composer-2.5:run-928ec91d-ccd0-40bb-952f-4e10d9894082", "enrich_notes": "Stormwater quality sizing uses MARC/APWA Level of Service (Value Ratings, Table 3-1), not a fixed WQv rainfall depth in this handbook. Detailed BMP dimensions and many infiltration design rates are deferred to the MARC/APWA BMP Manual. Topeka requires underdrain for bioretention and permeable pavement; full infiltration without underdrain needs in-situ infiltration between 1.0 and 11 in/hr and >3 ft separation to seasonally saturated soils/bedrock.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "trenton-nj", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/trenton-nj/", "data_url": "https://stormwateratlas.com/data/manuals/trenton-nj.json", "document_metadata": { "jurisdiction_name": "City of Trenton", "jurisdiction_level": "municipality", "state_code": "NJ", "document_title": "New Jersey Stormwater BMP Manual / N.J.A.C. 7:8 (capital MS4)", "version_or_edition": "Chapter 5: July 2023; Chapter 9.7: January 2026", "adoption_or_effective_date": "2023-07", "last_revised_date": "2026-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5). NRCS methodology computes WQDS runoff volume, peak rate, and hydrograph; BMPs such as small-scale bioretention must store/treat the entire WQDS volume.", "peak_flow_calculation_method": [ "USDA NRCS methodology (NRCS Runoff Equation and Dimensionless Unit Hydrograph)", "NRCS Curve Number (CN) method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Small-scale green infrastructure BMPs", "Small-scale bioretention systems", "Small-scale infiltration basins", "Green roofs", "Pervious paving systems", "Grass swales", "Cisterns", "Green Infrastructure MTDs / MTDs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Trenton MS4 follows NJDEP Stormwater BMP Manual", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Design Storm (WQDS): 1.25 inches", "page_or_section": "N.J.A.C. 7:8-5.5 / NJDEP BMP Manual" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv method: NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5).", "page_or_section": "Atlas context / N.J.A.C. 7:8-5.5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The capacity of the underdrain must be sufficient to allow the system to drain within 72 hours", "page_or_section": "Green Infrastructure BMPs, Ch. 9.7, page 74" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the bioretention system fails to drain the Water Quality Design Storm within 72 hours, corrective action must be taken", "page_or_section": "Ch. 9.7 Small-Scale Bioretention, page 49" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table (SHWT) must be at least 1 foot below the bottom of the gravel layer.", "page_or_section": "Green Infrastructure BMPs, Ch. 9.7, page 74" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the minimum depth of 18 inches may not be sufficient", "page_or_section": "Ch. 9.7 Stormwater Tree Pit, page 22" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The water depth above the soil bed should not exceed the maximum design depth of 12 inches", "page_or_section": "Ch. 9.7 Example 1, page 23" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "For the WQDS, the maximum depth of runoff is 18 inches at the down-gradient end of a sloped-bottom system", "page_or_section": "Ch. 9.7 Bioretention Swale, page 22" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "In sloped-bottom systems, the maximum longitudinal slope is 10%.", "page_or_section": "Ch. 9.7 Bioretention Swale, page 22" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NJDEP BMP Manual (Newark/Paterson pattern).", "fields_not_found": [] }, "source": { "document_url": "https://dep.nj.gov/wp-content/uploads/stormwater/bmp/njswbmp-chapter-9.7-small-scale-bioretention-systems-january-2026.pdf", "landing_page_url": "https://dep.nj.gov/stormwater/stormwater-management/bmp-manual/", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "trenton-nj.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 10, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "swale" ], "enriched_at": "2026-08-13T10:23:49.195Z", "enrich_model": "composer-2.5:run-d2a147a0-86c7-4a59-b1eb-d89d1a9a9f3c", "enrich_notes": "NJ WQDS cited in atlas as 1.25 in over 2 hr; corpus references WQDS volumes throughout Ch. 5 and 9.7. Underdrain bioretention: drain within 72 hr (24 hr in pedestrian areas). SHWT at least 1 ft below gravel layer (underdrain); Example 3 infiltration cites 2 ft minimum between basin bottom and SHWT. Sloped bioretention swale: max WQDS runoff depth 18 in at down-gradient end. Recharge/design rates in examples use half tested Ksat (e.g. 1 in/hr from 2 in/hr), not a single jurisdiction-wide design infiltration rate.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tucson-az", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tucson-az/", "data_url": "https://stormwateratlas.com/data/manuals/tucson-az.json", "document_metadata": { "jurisdiction_name": "City of Tucson", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Standards Manual for Drainage Design and Floodplain Management in Tucson, Arizona", "version_or_edition": "December 1989 (Revised July 1998); Chapter IV revised April 1998", "adoption_or_effective_date": "1989-12", "last_revised_date": "1998-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Threshold Retention required in Balanced/Critical Basins per the Stormwater Detention/Retention Manual; Critical Basins require a 15% reduction of the 2-, 10-, and 100-year events. Stormwater harvesting may offset Threshold Retention volume (Design Policy #10).", "peak_flow_calculation_method": [ "City of Tucson Flood Peak Estimator Procedure (basins ≤10 sq mi)", "Tucson Stormwater Management Study (TSMS) hydrology (preferred where available)", "HEC-1", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "Stormwater System Planner (HEC-1 / AutoCAD mapping component for TSMS)" ], "approved_bmp_categories": [ "Detention/Retention Basins", "Stormwater Harvesting", "Stormwater-Infiltration Systems (Dry Wells)", "Open Channels", "Channel Stabilization and Hydraulic Structures", "Storm Drains", "Culverts", "Street and Parking Lot Drainage" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Prepared for City of Tucson Department of Transportation Engineering Division", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Tucson Department of Transportation, Engineering Division", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "STANDARDS MANUAL FOR DRAINAGE DESIGN AND FLOODPLAIN MANAGEMENT IN TUCSON, ARIZONA", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STANDARDS MANUAL FOR DRAINAGE DESIGN AND FLOODPLAIN MANAGEMENT IN TUCSON, ARIZONA", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "DECEMBER, 1989 (REVISED JULY, 1998)", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "DECEMBER, 1989", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "REVISED JULY, 1998... CHAPTER IV: CITY OF TUCSON METHOD FOR ESTIMATING FLOOD PEAKS AND FLOOD HYDROGRAPHS (REVISED APRIL, 1998)", "page_or_section": "Title Page; Chapter IV" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "STANDARDS MANUAL FOR DRAINAGE DESIGN AND FLOODPLAIN MANAGEMENT IN TUCSON, ARIZONA... Prepared for City of Tucson", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "procedure for estimating 2-year, 5-year, 10-year, 25-year, 50-year, and 100-year flood peaks and flood hydrographs for watershed areas located within the City of Tucson", "page_or_section": "Chapter IV, Section 4.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Provide and describe Reservoir-Routing Calculation Sheets for each basin for the 2-year, 10-year, and 100-year design floods, at a minimum.", "page_or_section": "Chapter II, Section 2.3.1.6 Basin Design" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Compliance with these Threshold Retention requirements, which are described in the Stormwater Detention/Retention Manual, is now required... The volume utilized for stormwater harvesting may be used to offset the volume required for Threshold Retention. Stormwater harvesting has been added as Design Policy #10 in Chapter XIV", "page_or_section": "October 24, 1997 Cover Letter" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For those watersheds designated as Critical Basins, a 15% reduction in the 2-, 10-, and 100-year flow events will be required as a fair and equitable apportioning increment.", "page_or_section": "October 24, 1997 Cover Letter" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The City of Tucson Flood Peak Estimator Procedure shall be used to determine the design 100-year flood peak for drainage basins less than ten square miles in size.", "page_or_section": "Chapter I, Design Policies — Chapter IV" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "it is the strong preference of the City of Tucson that TSMS peak discharges be used in lieu of the procedures presented herein, whenever and wherever it is practicable to do so.", "page_or_section": "Chapter IV, Section 4.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "a City-approved hydrologic methodology (e.g., HEC-1) should be used to properly model the effects of any such controls.", "page_or_section": "Chapter IV, Section 4.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Using the Rational Formula, Q = CiA", "page_or_section": "Chapter X, Storm Drains Example 10.2" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The TSMS hydrologic modeling was accomplished using the Stormwater System Planner, a software package which includes a database manager, the HEC-1 hydrologic model, and an AutoCAD mapping component.", "page_or_section": "Conditions of Use, TSMS Hydrologic Data" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "CHAPTER VIII. OPEN-CHANNEL DESIGN... CHAPTER IX: Channel Stabilization and Hydraulic Structures... CHAPTER X: Storm Drains... CHAPTER XI: Culverts... CHAPTER XII: Street and Parking Lot Drainage... CHAPTER XIV. DETENTION/RETENTION BASINS... 14.5 Stormwater-Infiltration Systems", "page_or_section": "Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Mayor and Council has directed the City Engineer's office to require new developments to utilize stormwater harvesting to the maximum extent reasonably possible.", "page_or_section": "October 24, 1997 Cover Letter" }, { "field": "fields_not_found", "excerpt": "have a minimum vertical separation of 75 feet from the invert of the infiltration", "page_or_section": "p336" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Compliance with these Threshold Retention requirements, which are described in the Stormwater Detention/Retention Manual, is now required.", "page_or_section": "Chapter IV letter, page 5 (tucson-az-c0013)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "shall have a minimum vertical separation of 75 feet from the invert of the infiltration system to the elevation of the static ground-water table.", "page_or_section": "XIV. Detention/Retention Basins, 14.5 Stormwater-Infiltration Systems, item 3 (tucson-az-c0287)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "shall have a minimum vertical separation of 125 feet from the invert of the infiltration system to the elevation of the static ground-water table.", "page_or_section": "XIV. Detention/Retention Basins, 14.5 Stormwater-Infiltration Systems, item 4 (tucson-az-c0287)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "the rate of drainage shall be based on the results of a standard percolation test and a factor of safety of two (i.e., divide the field-test percolation rate by two).", "page_or_section": "XIV. Detention/Retention Basins, 14.5 item 9 (tucson-az-c0288)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "required to drain the basin in the time required (refer to Section 3.5 in Tucson Development Standard 10-01.0)", "page_or_section": "XIV. Detention/Retention Basins, 14.5 item 9 (tucson-az-c0288)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Pumping the retained water into a street for periods longer than four hours is normally not acceptable", "page_or_section": "XIV. Detention/Retention Basins, Design Policy (tucson-az-c0284)" }, { "field": "practice_mentions.swale", "excerpt": "limited to, lined and unlined channels, drainage swales, streets and alleys", "page_or_section": "II. Report Formats, 2.3.1.6 (tucson-az-c0124)" }, { "field": "practice_mentions.extended_detention", "excerpt": "DETENTION BASIN is a type of flood-control system which employs a reservoir as a means of delaying the downstream progress of floodwaters in a controlled manner.", "page_or_section": "Glossary (tucson-az-c0090)" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Detention/retention systems which utilize a method of subsurface disposal (i.e., dry wells, engineered basin floors, trenches, etc.)", "page_or_section": "XIV. 14.5 Stormwater-Infiltration Systems (tucson-az-c0287)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Numeric first-flush depth is defined in the companion Pima County/Tucson Detention and Retention Manual (tucson-az-detention), not as a standalone WQv formula in this drainage standards manual.", "fields_not_found": [] }, "source": { "document_url": "https://www.tucsonaz.gov/files/sharedassets/public/v/1/pdsd/documents/manuals/cot-drainage-manual-searchable.pdf", "landing_page_url": "https://www.tucsonaz.gov/Departments/Planning-Development-Services/Codes/Engineering-Codes", "retrieved_at": "2026-08-08T11:41:45.561Z", "original_filename": "cot-drainage-manual-searchable.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale" ], "enriched_at": "2026-08-13T10:25:01.272Z", "enrich_model": "composer-2.5:run-38ce7ed0-fe1c-4987-8518-9ee451e51d5f", "enrich_notes": "Threshold Retention volumes and numeric first-flush/WQv depth are referenced to Tucson Development Standard 10-01.0 (Stormwater Detention/Retention Manual), not defined numerically in these drainage-standards excerpts. Stormwater-infiltration (dry wells, engineered basin floors, trenches) specifies 75 ft or 125 ft minimum vertical separation from static groundwater (land-use dependent), percolation rate divided by two for design, and drain times per Manual Section 3.5—not quoted here in hours. Critical Basins require 15% reduction of 2-, 10-, and 100-year events. Pumping retained water to streets longer than four hours is normally not acceptable.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tulsa-ok", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tulsa-ok/", "data_url": "https://stormwateratlas.com/data/manuals/tulsa-ok.json", "document_metadata": { "jurisdiction_name": "City of Tulsa", "jurisdiction_level": "municipality", "state_code": "OK", "document_title": "Stormwater Management Criteria Manual", "version_or_edition": "June/October 2019", "adoption_or_effective_date": null, "last_revised_date": "2019-10", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Water quality control and post-construction stormwater pollution prevention plan requirements included. Technical criteria cover rainfall/runoff, channels, street drainage/inlets/storm sewers, and detention pond design.", "peak_flow_calculation_method": [ "Rational Method for applicable watershed sizes", "Design storm hydrology per Technical Provisions", "Storm sewers designed to pass the 1% (100-year) storm", "Detention pond design criteria; fee-in-lieu of onsite detention option" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Storm sewers and inlets", "Open channels", "Post-construction stormwater pollution prevention BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "CITY OF TULSA, OKLAHOMA", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Tulsa - Engineering Services Department", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Criteria Manual", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "June 2019 / October 2019", "page_or_section": "Cover / TOC" }, { "field": "document_metadata.last_revised_date", "excerpt": "October 2019", "page_or_section": "TOC footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Oklahoma Stormwater Law", "page_or_section": "TOC" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Storm sewers shall be designed to pass the 1% (100-year) storm", "page_or_section": "Street Drainage chapter" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Control", "page_or_section": "TOC / criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "RATIONAL METHOD / DESIGN STORM", "page_or_section": "Technical Provisions TOC" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Ponds", "page_or_section": "TOC" }, { "field": "practice_mentions.swale", "excerpt": "Open Channels and Swales ... Facilities shall be designed to convey the flood produced by the regulatory 1% (100- year) storm with one (1) foot of freeboard.", "page_or_section": "Stormwater Policy & Standards / page 310 (tulsa-ok-c0050)" }, { "field": "practice_mentions.swale", "excerpt": "A swale shall be designed within the overland drainage easement. The swale shall be sized to convey the regulatory 1% (100-year) flow rate under fully urbanized conditions", "page_or_section": "Stormwater Policy & Standards / page 310 (tulsa-ok-c0050)" }, { "field": "practice_mentions.extended_detention", "excerpt": "The peak flows from development shall be controlled by on-site detention, or by regional detention identified in the adopted City master drainage plans", "page_or_section": "Executive Summary Administrative Provisions / page 101 (tulsa-ok-c0017)" }, { "field": "practice_mentions.bioretention", "excerpt": "post-construction storm water controls such as ponds, wetlands, bioswales, or rain gardens, if known, should be defined.", "page_or_section": "Construction Phase Stormwater Pollution Prevention / page 1005 (tulsa-ok-c0158)" }, { "field": "practice_mentions.wet_pond", "excerpt": "For wet ponds, A. The bottom area will normally be inundated.", "page_or_section": "Maintenance and Design / page 1206 (tulsa-ok-c0165)" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "The use of wetlands for treatment of urban runoff water quality has been shown to be effective (Chapter 1000).", "page_or_section": "Maintenance and Design / page 1207 (tulsa-ok-c0166)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Tulsa SMCM 2019; confirm exact WQ sizing formulas from water quality control chapter. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.cityoftulsa.org/media/11859/stormwatermanagementcriteriamanual-june2019.pdf", "landing_page_url": "https://www.cityoftulsa.org/", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "tulsa-ok.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:25:27.796Z", "enrich_model": "composer-2.5:run-97d9749c-c4d3-492f-874e-3bdf37ce37f4", "enrich_notes": "Excerpts are largely TOC, policy, hydrology (rational/SCS), channels, storm sewer, construction SWP3, and maintenance. Chapter 1100 Low Impact Development is listed in the TOC but no LID/BMP sizing chapter text was provided. Detention freeboard table references excavated ponds >18-inches and 1 ft freeboard but no WQv depth, drawdown times, infiltration rates, or bioretention/permeable pavement design depths.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "vancouver-wa", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/vancouver-wa/", "data_url": "https://stormwateratlas.com/data/manuals/vancouver-wa.json", "document_metadata": { "jurisdiction_name": "City of Vancouver", "jurisdiction_level": "municipality", "state_code": "WA", "document_title": "Surface Water Management Design and Construction Requirements (Section 4 General Requirements)", "version_or_edition": "FINAL 2/18/2025", "adoption_or_effective_date": "2025-02-18", "last_revised_date": "2025-02-18", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "Adopts Ecology Stormwater Management Manual for Western Washington (SWMMWW) Minimum Requirements by reference (MR #1–#9 including runoff treatment and flow control). Local Section 4 General Requirements supplement/clarify SWMMWW for Vancouver conditions, including bioretention, flow control & infiltration systems, and UIC program alignment.", "peak_flow_calculation_method": [ "Ecology SWMMWW continuous simulation / flow control", "WWHM / HSPF (per SWMMWW)", "City General Requirements Section 4" ], "required_hydrologic_hydraulic_software": [ "WWHM", "HSPF" ], "approved_bmp_categories": [ "Bioretention areas", "Flow control facilities", "Infiltration systems", "Runoff treatment BMPs (SWMMWW)", "LID BMPs", "Source control BMPs", "Construction stormwater BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Vancouver", "page_or_section": "Section 4 header" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Vancouver", "page_or_section": "Coverage" }, { "field": "document_metadata.state_code", "excerpt": "Washington State Department of Ecology", "page_or_section": "§4-1" }, { "field": "document_metadata.document_title", "excerpt": "SURFACE WATER MANAGEMENT DESIGN AND CONSTRUCTION REQUIREMENTS", "page_or_section": "Section 4" }, { "field": "document_metadata.version_or_edition", "excerpt": "FINAL 2/18/2025", "page_or_section": "Footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "FINAL 2/18/2025", "page_or_section": "Footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "FINAL 2/18/2025", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "supplement and clarify the Stormwater Management Manual for Western Washington (Stormwater Manual)", "page_or_section": "§4-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Minimum Requirements ... Flow Control ... Ecology's Stormwater Manual", "page_or_section": "§4-1.01" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Flow Control & Infiltration Systems", "page_or_section": "§4-5" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Manual for Western Washington (SWMMWW). 2. Minimum Requirement #2: Construction Stormwater Pollution Prevention Plan (SWPPP) – Discuss whether a SWPPP will be required for the project (full or abbreviated) due to the thresholds for hard surfaces and disturbed area. Submi", "page_or_section": "p. 10" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Areas", "page_or_section": "§4-7.01" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "SWMMWW design storms 2/10/25/50/100", "page_or_section": "SWMMWW / coverage note" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of infiltration facilities shall be a minimum of five (5) feet above seasonal high water or an impermeable layer", "page_or_section": "Section 4-5.10 Infiltration Facility Setbacks (4-35)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of roof downspout infiltration systems shall be a minimum of five (5) feet above seasonal high water or an impermeable layer", "page_or_section": "Section 4-10.02 General Protections/Setbacks (4-48)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum ponding level in all facilities is 1 foot.", "page_or_section": "Section 4-7.01 Bioretention Areas (4-42)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The maximum allowed design infiltration rate is 250 inches/hour.", "page_or_section": "Section 4-5.08 Infiltration Design Rates (4-34)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "An assumed twelve (12) inches per hour infiltration rate may be used for bioretention soil mixes (BSM) that meet the requirements of the Stormwater Manual.", "page_or_section": "Section 4-7.01 Bioretention Areas (4-41)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Local Section 4 (2025) + SWMMWW adoption via VMC 14.25. Return periods mirrored from wa-state-western / SWMMWW.", "fields_not_found": [] }, "source": { "document_url": "https://www.cityofvancouver.us/wp-content/uploads/2024/12/Section-4-Storm-Gen-Reqs-2025-with-appendix.pdf", "landing_page_url": "https://www.cityofvancouver.us/government/department/public-works/water-sewer-and-stormwater/surface-water-stormwater-design-construction-requirements/", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "vancouver-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 250, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:29:17.764Z", "enrich_model": "composer-2.5:run-0f0222eb-0b17-48d8-b02f-f38945d207a0", "enrich_notes": "Vancouver Section 4 (2025) supplements SWMMWW; WQv depth, media depths, ED drawdown, and most BMP sizing criteria are by reference to Ecology Stormwater Manual Vol. III/V. Local numeric highlights: infiltration base minimum 5 ft (60 in) to seasonal high water with possible 3 ft reduction per mounding analysis; maximum allowed design infiltration rate 250 in/hr with Table D-3 correction factors (base CF 2); bioretention may use assumed 12 in/hr for qualifying BSM in WWHM2012/MGS Flood; max ponding 1 ft (12 in); marginal site infiltration threshold <2 in/hr triggers PE design for small-project downspout systems.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "waco-tx", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/waco-tx/", "data_url": "https://stormwateratlas.com/data/manuals/waco-tx.json", "document_metadata": { "jurisdiction_name": "City of Waco", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "iSWM Criteria Manual for Site Development and Construction", "version_or_edition": "Revised January 2015", "adoption_or_effective_date": "2015-01", "last_revised_date": "2015-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 25, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQv) based on 1.5 inches of rainfall (85th percentile storm). Streambank Protection: control 1-year, 24-hour storm; Conveyance: 25-year; Flood Mitigation: 100-year.", "peak_flow_calculation_method": [ "Rational Method", "SCS Unit Hydrograph Method", "Streambank Protection Volume (SPV)", "25-year conveyance / 100-year flood mitigation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Enhanced swales", "Detention", "Sand filters / filter boxes", "Infiltration wells and trenches" ] }, "evidence": [ { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "3.2.3 Option 2, page 29" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treat the Water Quality Protection Volume ... for runoff resulting from rainfall of 1.5 inches (85th percentile storm).", "page_or_section": "3.2.3 Option 2, page 28" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet Pond Limit maximum normal pool depth to about 4 ft (dugout)", "page_or_section": "Table 3.19 Physiographic Factors, page 61" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Third-party sources could include Technology Acceptance Reciprocity Partnership, Technology Assessment Protocol – Ecology, or others.", "page_or_section": "Table 3.2 footnote, TriSWM Appendix page 112" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "NCTCOG iSWM regional criteria — confirm city adoption / local amendments. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://iswm.nctcog.org/Documents/iSWM_Criteria_Manual_01142015.pdf", "landing_page_url": "https://iswm.nctcog.org/criteria-manual.html", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "waco-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "Technology Acceptance Reciprocity Partnership; Technology Assessment Protocol – Ecology", "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:31:22.258Z", "enrich_model": "composer-2.5:run-d06cbbd4-6d13-460b-b964-95f170b55a9a", "enrich_notes": "Criteria Manual defers facility-specific design dimensions to the Site Development Controls Technical Manual. Table 3.17/3.4 list practice-specific depth-to-water-table values (often 2 ft; infiltration trenches 4 ft in site applicability; enhanced swales 1 ft below WT; reservoir/aquifer notes 2–4 ft). Minimum soil infiltration >0.5 in/hr applies to infiltration trenches, drywells, soakage trenches, and modular porous pavers.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "west-palm-beach-fl", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/west-palm-beach-fl/", "data_url": "https://stormwateratlas.com/data/manuals/west-palm-beach-fl.json", "document_metadata": { "jurisdiction_name": "City of West Palm Beach", "jurisdiction_level": "municipality", "state_code": "FL", "document_title": "SFWMD Environmental Resource Permit Applicant's Handbook Volume II (Basis of Review)", "version_or_edition": "Effective July 4, 2010 (draft ERP Vol II mirror)", "adoption_or_effective_date": "2010-07-04", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "SFWMD ERP AH Vol II: wet detention volume for the first inch of runoff from the developed project (or 2.5 in over the basin for projects with ≥50% impervious / special cases per rule); dry detention = 75% of wet; retention = 50% of wet. Quantity: off-site discharge typically based on 3-day / 25-year storm unless local criteria are more stringent; 100-year / 3-day considered for flood protection / finished floors.", "peak_flow_calculation_method": [ "3-day / 25-year off-site discharge (default)", "100-year / 3-day flood considerations", "Retention / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Dry retention / detention", "Exfiltration trenches", "Swales / pretreatment", "Other SFWMD-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of West Palm Beach is within SFWMD and follows ERP Applicant's Handbook Vol II", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet detention volume shall be provided for the first inch of runoff", "page_or_section": "SFWMD Vol II water quality criteria" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project, or the total runoff of 2.5 inches times the percentage of imperviousness, whichever is greater.", "page_or_section": "4.2.1 Volumetric Requirements, page 17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The required water quality system for one inch of runoff detention or one half inch of runoff retention in the master system for the total developed site.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.swale", "excerpt": "Onsite works such as swales and dikes shall be used to allow the passage of drainage from offsite areas to downstream areas.", "page_or_section": "3.8 Offsite Lands, page 14" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.3.1 Description, page 26" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The individual sites must provide the remainder (2.5\" x % impervious - one inch) which may be in exfiltration trench.", "page_or_section": "3.9 Minimum Drainage (b)(1)(a), page 14" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet detention volume shall be provided for the first inch of runoff from the developed project", "page_or_section": "4.2.1 Volumetric Requirements, page 17" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry retention/detention areas shall have mechanisms for returning the groundwater level in the area to the control elevation.", "page_or_section": "5.3.3 Dry Retention/Detention Areas, page 26" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Man-made or natural depressional areas where the basin bottom is graded flat and turf is established to promote infiltration and stabilize the basin slopes", "page_or_section": "5.3.1 Description, page 26" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via SFWMD ERP AH Vol II. Prefer city-specific drainage criteria if a durable public PDF appears.", "fields_not_found": [] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/draft_erp%20vol%20ii%20swerp%20ii_2104_10.pdf", "landing_page_url": "https://www.sfwmd.gov/", "retrieved_at": "2026-08-10T10:18:37.456Z", "original_filename": "west-palm-beach-fl.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:32:10.465Z", "enrich_model": "composer-2.5:run-75f92374-9bae-429d-a3ea-ab35b24496c8", "enrich_notes": "SFWMD ERP AH Vol II (Aug 2014): WQ volumetric rule uses wet detention for the first inch of project runoff or 2.5 in × percent impervious, whichever is greater (§4.2.1). Master-planned commercial subdivisions may provide 1 in detention or 0.5 in retention in the master system with remainder on lots, sometimes via exfiltration trench (§3.9). Residential minimum drainage cites 3/8 in/day bleed and ≤12-day drawdown of water surfaces, not SCM hour limits. Subsurface exfiltration requires site test data; no universal design infiltration rate in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wichita-ks-vol2", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wichita-ks-vol2/", "data_url": "https://stormwateratlas.com/data/manuals/wichita-ks-vol2.json", "document_metadata": { "jurisdiction_name": "City of Wichita and Sedgwick County", "jurisdiction_level": "municipality", "state_code": "KS", "document_title": "Stormwater Manual for the City of Wichita and Sedgwick County — Volume 2, Technical Guidance — Chapter 1 Overview of Integrated Site Design", "version_or_edition": "Volume 2, Technical Guidance, Chapter 1", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQv) is runoff from the 85th percentile rain event, identified as 1.2 inches of rainfall for Wichita/Sedgwick County (6-hour minimum dry interval). Treat WQv to remove 80% of TSS. Channel Protection Volume (CPv) is extended detention of the 1-year, 24-hour event (2.8 inches) for at least 24 hours centroid-to-centroid, or retain the pre-/post-development difference on-site.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Preferred Site Design / non-structural practices (minimize impervious area, minimize soil disturbance, preserve natural areas, promote infiltration)", "Structural stormwater controls — detention, filtration, or infiltration (detention and retention ponds, constructed wetlands, bioretention areas, infiltration trenches, engineered swales)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The Stormwater Manual for the City of Wichita and Sedgwick County consists of three volumes", "page_or_section": "Section 1.1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "consistent with the stormwater policies adopted by the City of Wichita and Sedgwick County", "page_or_section": "Section 1.1" }, { "field": "document_metadata.state_code", "excerpt": "City of Wichita and Sedgwick County", "page_or_section": "Section 1.1" }, { "field": "document_metadata.document_title", "excerpt": "Volume 2 – Technical Guidance Manual... OVERVIEW OF INTEGRATED SITE DESIGN", "page_or_section": "Chapter 1 cover / Section 1.1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Volume 2, Technical Guidance Page 1 - i... CHAPTER 1", "page_or_section": "Chapter 1 header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "the stormwater policies adopted by the City of Wichita and Sedgwick County (and presented in Volume 1), and the stormwater management and floodplain regulations for each jurisdiction.", "page_or_section": "Section 1.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The Channel Protection Volume (CPv) is the volume of temporary detention required to detain the development site runoff for the 1-year, 24-hour rain event (of 2.8\")", "page_or_section": "Table 1-1 / Section 1.3.3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "post-development peak discharges for the 2-year through 100-year, 24-hour rain events do not exceed pre-development values at the project boundary", "page_or_section": "Table 1-1 Step 4 Flood Protection / Section 1.3.5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the site must be designed to safely pass or temporarily store the resulting flows from the full build-out 100-year storm event without flooding structures or other critical features.", "page_or_section": "Section 1.3.4 On-Site Conveyance" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Water Quality Protection Volume (WQv) is the volume of runoff from the development as a result of the 85th percentile rain event. In the Wichita and Sedgwick County area, this is the 1.2 inch rain event. Water quality protection must be achieved by treating the WQv to remove 80% of the total suspended solids", "page_or_section": "Table 1-1 Step 1 / Section 1.3.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Based on a rainfall analysis, 1.2 inches of rainfall has been identified as the depth corresponding to the 85th percentile storm for the City of Wichita and Sedgwick County (using a 6-hour minimum dry interval to separate \"events\").", "page_or_section": "Section 1.3.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "the controls consist of detention, filtration, or infiltration facilities that remove TSS from the runoff, and/or detain runoff for quantity control (CPv and floods). Examples include detention and retention ponds, constructed wetlands, bioretention areas, infiltration trenches, and engineered swales.", "page_or_section": "Section 1.5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Preferred Site Design\" (PSD)... site designs that minimize impervious areas, minimize disturbance of site soils, preserve natural areas, and promote infiltration", "page_or_section": "Section 1.4" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In the Wichita and Sedgwick County area, this is the 1.2 inch rain event.", "page_or_section": "Table 1-1 / Section 1.3.1, page 1-3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "1.2 inches of rainfall has been identified as the depth corresponding to the 85th percentile storm", "page_or_section": "Section 1.3.2, page 1-5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treat the first 1.2 inches of runoff (or less for smaller storms) to the 80% TSS removal standard", "page_or_section": "Section 1.3.2, page 1-5" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the development site runoff for the 1-year, 24-hour rain event (of 2.8\") for a minimum of 24 hours (centroid-to-centroid)", "page_or_section": "Table 1-1 Step 2, page 1-3" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Channel protection is achieved by providing 24 hours of extended detention on-site for the post-developed runoff generated by the 1-year, 24-hour rainfall event.", "page_or_section": "Section 1.3.3, page 1-5" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "must either be detained for at least 24-hours, or the difference in pre- and post-development runoff volume for that event must be retained on-site", "page_or_section": "Section 1.3.6 Summary, page 1-7" }, { "field": "practice_mentions", "excerpt": "Examples include detention and retention ponds, constructed wetlands, bioretention areas, infiltration trenches, and engineered swales.", "page_or_section": "Section 1.5, page 1-8" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Source PDF is Volume 2 Chapter 1 only (~10 pages overview). WQv (1.2 in / 85th percentile / 80% TSS), CPv (1-year 24-hr / 2.8 in), and flood peak matching (2- through 100-year) are stated, but hydrologic calculation methods, software, detailed BMP design criteria, and document dates are deferred to other volumes/chapters not in this extract. Intermediate return periods between 2 and 100 years are required by \"2-year through 100-year\" language but not individually listed here. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "design_parameters.wqv_depth_inches" ] }, "source": { "document_url": "https://www.wichita.gov/DocumentCenter/View/11104/Volume-2-03---Chapter-1-PDF", "landing_page_url": "https://www.wichita.gov/631/Manuals-and-Policies", "retrieved_at": "2026-08-08T10:20:00.000Z", "original_filename": "wichita-ks-vol2.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:34:18.811Z", "enrich_model": "composer-2.5:run-18669d27-d4ad-4304-96bd-884034cac275", "enrich_notes": "Volume 2 Chapter 1 is ISD overview only. WQv = 1.2 in (85th percentile, 6-hour dry interval); 80% TSS on WQv runoff. CPv = 1-year 24-hour event (2.8 in rainfall stated for Step 2) with minimum 24-hour centroid-to-centroid extended detention or retain pre/post volume difference on-site. Flood control: 2-year through 100-year 24-hour peaks ≤ pre-development at boundary. Detailed BMP sizing, infiltration rates, and facility criteria deferred to Vol. 2 Chapters 2–5.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wilmington-de", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wilmington-de/", "data_url": "https://stormwateratlas.com/data/manuals/wilmington-de.json", "document_metadata": { "jurisdiction_name": "City of Wilmington", "jurisdiction_level": "municipality", "state_code": "DE", "document_title": "Delaware Sediment and Stormwater / Wet Pond Standards (MS4 partial)", "version_or_edition": "Section 13.0 Wet Ponds (DRAFT)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "DNREC Sediment and Stormwater Program. Wet ED Ponds receive RPv credit via 48-hour extended detention of the Resource Protection Volume; exact RPv depth in Delaware Sediment and Stormwater Regulations.", "peak_flow_calculation_method": [ "Site-adjusted RCN", "Cv / Fv quantity management per DNREC" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Quantity Management Pond", "Wet Extended Detention (ED) Pond", "Other DNREC-approved BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Wilmington DE MS4 follows DNREC Sediment and Stormwater standards", "page_or_section": "Coverage note" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "a Wet ED Pond must provide 48 hours extended detention for the RPv runoff volume", "page_or_section": "13.6 Wet Pond Design Criteria (page 11); Table 13.2 summary (page 5)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum depth = 4'; maximum depth = 8'", "page_or_section": "13.2 Table 13.2 Design Criteria Geometry (page 5); 13.6 Permanent Pool Depth (page 12)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The forebay should have a length to width ratio of 2:1 or greater", "page_or_section": "13.5 Wet Pond Pretreatment Criteria (page 10)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "a diameter capable of draining the Wet Pond within 24 hours", "page_or_section": "13.6 Pond Drain (page 14)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high groundwater table is two feet or more below the proposed Wet Pond invert", "page_or_section": "13.3 Wet Pond Feasibility Criteria – Soils (page 8)" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Partial coverage via wet-pond chapter (Dover pattern).", "fields_not_found": [] }, "source": { "document_url": "https://documents.dnrec.delaware.gov/Admin/Public-Notices/WSS20260001/13-0-Wet-Ponds-DRAFT-strikethrough.pdf", "landing_page_url": "https://dnrec.delaware.gov/watershed-stewardship/sediment-stormwater/", "retrieved_at": "2026-08-10T10:27:43.524Z", "original_filename": "wilmington-de.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "wet_pond" ], "enriched_at": "2026-08-13T10:34:45.744Z", "enrich_model": "composer-2.5:run-6c2f7b27-4f58-4510-af40-535376cf6d39", "enrich_notes": "Wilmington DE wet-pond chapter (DNREC pattern): Wet ED Ponds require 48-hour extended detention of RPv for credit; permanent pool min 4 ft (max 8 ft); forebay L:W ≥2:1; RPv/WQv inch depth not stated in this chapter (see DE Sediment and Stormwater Regulations).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wilmington-nc", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/wilmington-nc/", "data_url": "https://stormwateratlas.com/data/manuals/wilmington-nc.json", "document_metadata": { "jurisdiction_name": "City of Wilmington", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (City Comprehensive Stormwater Ordinance / coastal MS4)", "version_or_edition": "Revised: 1-3-2017 (MDC chapter)", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Wilmington stormwater permitting relies on NCDEQ Stormwater Design Manual Minimum Design Criteria. Combined SCM design volume must handle the required storm depth for the applicable program (often 1\" for runoff treatment under 15A NCAC 02H .1021(6) for non-coastal HQW/ORW; coastal/SA waters follow applicable rule depths). Design volume based on build-out runoff from surfaces draining to the system.", "peak_flow_calculation_method": [ "NCDEQ MDC outlet erosion protection for 10-year peak", "City Comprehensive Stormwater Ordinance criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "SCM devices per 15A NCAC 02H .1051–.1062" ] }, "evidence": [ { "field": "design_criteria.water_quality_volume_method", "excerpt": "combined design volume of all SCMs ... required storm depth ... one inch", "page_or_section": "NCDEQ C-0 GENERAL MDC 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" }, { "field": "practice_mentions.bioretention", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.swale", "excerpt": "and depending upon native soils, vegetated swales, level spreader-filter strips, and berms.", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NCDEQ Design Manual MDC (same pattern as Cary). City coastal ordinance may impose additional SA/ORW depths not fully extracted here. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.wilmingtonnc.gov/Development-Business/Development-Review/Stormwater-Permits", "retrieved_at": "2026-08-10T10:02:27.846Z", "original_filename": "wilmington-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:35:03.167Z", "enrich_model": "composer-2.5:run-f83db882-a551-44be-b2c7-5d386cf554fb", "enrich_notes": "Corpus is NCDEQ Stormwater BMP Manual C-0 general MDC only (pages 2–7). Device-specific MDC under Rules 15A NCAC 02H .1051–.1062 and Part C are referenced but not excerpted. Required storm depth varies by program; excerpt cites 1 inch for non-coastal HQW/ORW runoff treatment under .1021(6). Wilmington coastal SA/ORW depths may differ per local ordinance. GENERAL MDC 6 requires drawdown capability but no maximum hours. Wet ponds and wetlands mentioned for maintenance pumping only.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "winston-salem-nc", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/winston-salem-nc/", "data_url": "https://stormwateratlas.com/data/manuals/winston-salem-nc.json", "document_metadata": { "jurisdiction_name": "City of Winston-Salem", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "Infrastructure Development Standards (Winston-Salem / Forsyth County)", "version_or_edition": "2020 (Revised April 2020)", "adoption_or_effective_date": null, "last_revised_date": "2020-04", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Stormwater management and permitting administered under City Code Chapter 75 with NCDEQ Stormwater Design Manual MDC (85% TSS SCMs; first-inch / 1-year rate criteria commonly applied per city post-construction permit process). Infrastructure Development Standards cover storm drain systems and stormwater management process (Sections IV / VI / VII).", "peak_flow_calculation_method": [ "Storm drain system design standards (Section IV)", "Stormwater management permitting process", "NCDEQ Land Quality / stormwater standards coordination" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "NCDEQ-approved SCMs (85% TSS)", "Storm drain systems", "Post-construction stormwater management facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Winston-Salem", "page_or_section": "Applicability" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Winston Salem", "page_or_section": "Standards apply" }, { "field": "document_metadata.state_code", "excerpt": "properties shall be coordinated with NCDEQ to determine the presence of wetlands and/or jurisdictional waters prior to final approval. COMPLETENESS CERTIFICATION: I, , PE have reviewed the attached plans prepared under my supervision. Furthermore, I certify that they, along wi", "page_or_section": "p. 25" }, { "field": "document_metadata.document_title", "excerpt": "Infrastructure Development Standards", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "2020 Revised April 2020", "page_or_section": "Filename / cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "most current standards of the Land Quality Section of the NCDEQ", "page_or_section": "Checklist" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "C. STORMWATER MANAGEMENT", "page_or_section": "Section IV-14" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Storm Drain System", "page_or_section": "Section IV-5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Management Permit / NCDEQ", "page_or_section": "Section VI / checklist" }, { "field": "practice_mentions.swale", "excerpt": "Identify and label all proposed and existing stormwater conveyance systems including but not limited to storm drainage inlets, catch basins, junction boxes etc. ... (Indicate type and size of conveyance, e.g. storm drainage pipe, grass swale, diversion berms etc.)", "page_or_section": "VI-23 / Checklist 4" }, { "field": "practice_mentions.swale", "excerpt": "All ditches and swales shall be indicated on the drawings complete with spot elevations, slopes, typical sections and liner materials.", "page_or_section": "IV-6 / Storm Drain System" }, { "field": "practice_mentions.extended_detention", "excerpt": "Acceptable mitigation alternatives include on-site detention to reduce post construction runoff rates and volumes and natural channel stabilization measures to control channel degradation.", "page_or_section": "VI-17 / Checklist 2" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Include tables of results comparing pre and post development peak discharges and increases as well as routed discharges and drawdown times for applicable storm events", "page_or_section": "VI-18 / Checklist 3 General Items" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A sealed geotechnical engineering analysis report including details of subsurface exploration which shows the investigation of the location of the seasonally high groundwater elevation if this elevation is required to be ascertained per the North Carolina Division of Environmental Quality (NCDEQ) Stormwater Design Manual.", "page_or_section": "VI-18 / Checklist 3" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "IDS is process/infrastructure-heavy; numeric post-construction criteria live mainly in Chapter 75 ordinance + NCDEQ manual. Consider supplementing with ordinance PDF later. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.cityofws.org/DocumentCenter/View/14134/Infrastructure-Development-Standards-2020-Revised-April-2020-PDF", "landing_page_url": "https://www.cityofws.org/", "retrieved_at": "2026-08-10T08:30:22.061Z", "original_filename": "winston-salem-nc.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T10:35:24.561Z", "enrich_model": "composer-2.5:run-01f20c54-b1ae-42ce-baf4-ed83255963a4", "enrich_notes": "Infrastructure Development Standards (April 2020) emphasize permit workflow, storm drain system standards (NCDOT drainage guidelines, 15 in. min pipe), and post-construction checklists referencing City Code Chapter 75 and the NCDEQ Stormwater Design Manual for SCM sizing, geotechnical SHWT, and low-density guidance. No explicit numeric SCM design parameters (WQv depth, media depths, drawdown hours, infiltration rates) appear in the provided excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "worcester-ma", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/worcester-ma/", "data_url": "https://stormwateratlas.com/data/manuals/worcester-ma.json", "document_metadata": { "jurisdiction_name": "City of Worcester", "jurisdiction_level": "municipality", "state_code": "MA", "document_title": "Massachusetts Stormwater Management Handbook (city follows MassDEP Standards)", "version_or_edition": "Third Edition / 2023 draft handbook mirror", "adoption_or_effective_date": null, "last_revised_date": "2023-12", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Required runoff depth multiplied by total post-construction impervious site area (MassDEP Stormwater Management Standards / Handbook). Includes recharge, TSS removal, and peak-rate attenuation standards.", "peak_flow_calculation_method": [ "NRCS Technical Release WinTR20 Project Formulation Method", "WinTR55 Small Watershed Hydrology Method" ], "required_hydrologic_hydraulic_software": [ "WinTR-20", "WinTR-55" ], "approved_bmp_categories": [ "Non-Structural", "Structural Pretreatment", "Structural Treatment", "Structural Conveyance", "Structural Infiltration", "Structural Other" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Worcester follows MassDEP Stormwater Handbook / Standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Performance Removal Curves and the MassDEP pollutant removal credits – i.e., the EPA-PRCs and MassDEP pollutant removal credits assume that the SCM has been designed with proper pretreatment in accordance with the Appendix A Structural SCM Specifications and the Massachusett", "page_or_section": "p. 30" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "calculated as the required runoff depth multiplied by the total post-construction impervious site area", "page_or_section": "MassDEP Handbook" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Required WQv is at least 1.0 inch times the total impervious area of the post-development site.", "page_or_section": "Table 2-4d / page 2-33" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Media Filters must be sized to treat the water quality volume (1.0 inch)", "page_or_section": "Appendix A Media Filters / A-102" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "conduct drawdown analysis to ensure the design volume from impervious area will infiltrate over 3-days based on Step 3 \"Drawdown within 72 Hours\".", "page_or_section": "Chapter 6 / page 6-36" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Computations must reflect drawdown within the 72-hour period for whatever volume is directed to the recharge practice.", "page_or_section": "Chapter 6 Step 3 / page 6-36" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance from bottom of SCM to SHGW9 2-ft", "page_or_section": "Table 2.5 setback table / page 2-55" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Grass channels and dry water quality swales must be at least 2 feet above seasonal high groundwater.", "page_or_section": "Table 2-4d / page 2-33" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide minimum of two feet of separation between the bed bottom and the seasonal high groundwater elevation", "page_or_section": "Appendix A Porous Pavement / A-158" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The depth of the soil media must be between 2 to 4 feet.", "page_or_section": "Appendix A Bioretention / A-72" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the bioretention area must have a soil media with a depth of at least 30 inches to create anoxic conditions", "page_or_section": "Appendix A Bioretention / A-72" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum acceptable final soil infiltration rate is 0.01 inches per hour.", "page_or_section": "Appendix A Infiltration Basin / A-142" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water levels in the extended detention wetlands may increase by as much as three feet after a storm, and return gradually to normal within 24 hours of the rain event.", "page_or_section": "Appendix A Extended Detention Wetlands / A-86" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "For design purposes, use 72 hours to evaluate dewatering, using the storm that produces 1.0 inch of runoff", "page_or_section": "Appendix A Media Filters / A-102" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "No durable standalone city design-manual PDF; MassDEP handbook is chaptered — used municipal mirror of 2023 draft with appendices (same source as ma-state-draft).", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.ashlandmass.com/DocumentCenter/View/13272/MassDEP-Handbook_DRAFT-6_2023-12-14_withAppendices-2", "landing_page_url": "https://www.mass.gov/guides/massachusetts-stormwater-handbook-and-stormwater-standards", "retrieved_at": "2026-08-10T09:45:18.895Z", "original_filename": "worcester-ma.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:35:42.864Z", "enrich_model": "composer-2.5:run-7bd9d5d9-b22e-4581-b100-e2d5e71a179f", "enrich_notes": "Massachusetts Stormwater Handbook (Worcester follows MassDEP). WQv = 1.0 in × post-development impervious area. Infiltration and many SCMs require 2 ft SHGW separation (24 in); porous pavement bed bottom also 2 ft. Recharge/infiltration drawdown within 72 hours. Bioretention soil media 2–4 ft (30 in if TMDL nitrogen). Extended detention wetland pool may rise ~3 ft and return within 24 hr. Min acceptable infiltration basin soil rate 0.01 in/hr; rapid soils >2.4 in/hr trigger stricter pretreatment. Porous pavement: max slope 5%, subbase ≥40% voids, 2 ft SHGW separation.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "yonkers-ny", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/yonkers-ny/", "data_url": "https://stormwateratlas.com/data/manuals/yonkers-ny.json", "document_metadata": { "jurisdiction_name": "City of Yonkers", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "New York State Stormwater Management Design Manual (adopted; applies in Yonkers)", "version_or_edition": "July 31, 2024", "adoption_or_effective_date": "2024-07-31", "last_revised_date": "2024-07-31", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "USDA NRCS TR20", "HydroCAD", "Pond Pack", "StormCAD", "Hydraflow", "HEC-HMS" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Practices", "Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "expected to increase by 10 to 20% (NYSDEC 2020). These adjustments should be factored into the design and construction of new stormwater management and control structures to ensure they sufficiently account for the effects of climate change, reducing future flood risk and pr", "page_or_section": "p. 28" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "or other individual hired by the municipality Learn about the resources the local program has at its disposal. If government staff are being trained, develop a maintenance plan that is consistent with their knowledge and understanding. Be aware of equipment and materials o", "page_or_section": "p. 323" }, { "field": "document_metadata.state_code", "excerpt": "DAM SAFETY SECTION 50 WOLF ROAD ALBANY, NEW YORK 12233-3507 --- page 369 --- GUIDELINES FOR DESIGN OF DAMS TABLE OF CONTENTS SECTION TITLE PAGE Preface to the January 1 1989 Edition 1 Introduction 2 Gravity Dams Modification 2 Definitions 3 3 Hazard Classification 5 4 De", "page_or_section": "pp. 363–370" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT DESIGN MANUAL", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-year, 2-year, 10-year, and 100-year", "page_or_section": "Table 4.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) 90% Rule: WQv (acre-feet) = (P ∙ Rv ∙ A) / 12 Rv = 0.05+0.009(I) I = Impervious Cover (Percent) P(inches) = 90% Rainfall Event Number (See Figure 4.1) 2 A = Contributing Area (acres) Runoff Reduction Volume (RRv) RRv (acre-feet) = Reduction of", "page_or_section": "p. 43" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "TR-55 and TR-20 (or approved equivalent) shall be used to determine peak discharge rates.", "page_or_section": "Section 4.6" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Hydraulic and hydrologic modeling software, such as USDA NRCS TR20, HydroCAD, Pond Pack, StormCAD, Hydraflow, and Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS) and others, shall be used", "page_or_section": "Section 4.9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Acceptable practices are divided into five groups, including: I. Stormwater Ponds... II. Stormwater Wetlands... III. Infiltration Practices... IV. Filtering Practices... V. Open Channel Practices", "page_or_section": "Section 3.3.1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "urban stormwater runoff 2. To provide design standards on the most effective stormwater management approaches including: o Incorporation of runoff reduction achieved by infiltration, groundwater recharge, reuse, recycle, evaporation/evapotranspiration through the use of runoff", "page_or_section": "p. 11" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "90th percentile rainfall 1.20 inches (Section 4.2)", "page_or_section": "Chapter 7, Table 7.1" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WATER QUALITY VOLUME (WQV) - The volume of stormwater runoff, generated from the 90th percentile rain event", "page_or_section": "Glossary" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Provide a mechanism that can completely drain the pond in 24 hrs", "page_or_section": "Fact Sheet: Wet Pond (P-2), TREATMENT" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min 2 ft separation to seasonal high-water table or bedrock", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-5)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide a 2' separation distance to water table.", "page_or_section": "Table 3.5 Watershed/Regional Selection Matrix, Ponds" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of filter media shall be 30 inches min and 48 inches max", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), TREATMENT" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max ponding is 12 inches (WQv) and 18 inches (Extreme Flood)", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), TREATMENT" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underlying soils shall have an min. infiltration rate of 0.50 inch/hr", "page_or_section": "Fact Sheet: Infiltration Bioretention (F-4), FEASIBILITY" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size outlet structure to detain WQv for 24 hrs (12 hrs to trout waters)", "page_or_section": "Fact Sheet: Wet Pond (P-2), FEASIBILITY" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Min. flow path of 1.5:1 (length to relative width) from all inlet points to the outflow points across the pond", "page_or_section": "Fact Sheet: Wet Pond (P-2), TREATMENT" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be a min of 2 ft and a max of 8 ft", "page_or_section": "Fact Sheet: Dry Swale (O-1), TREATMENT" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Channel slope shall be 0.50% min and 4.0% max", "page_or_section": "Fact Sheet: Dry Swale (O-1), TREATMENT" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via NYS Stormwater Management Design Manual (same pattern as Rochester). Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://extapps.dec.ny.gov/fs/projects/24-25DraftCGPDesignManual/Manual.SW.CGP.2024-07-31.Design_Manual_Issued_2024-07-31.pdf", "landing_page_url": "https://dec.ny.gov/environmental-protection/water/water-quality/stormwater/construction-stormwater-toolbox", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "yonkers-ny.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 24, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:37:04.034Z", "enrich_model": "composer-2.5:run-51f1b519-de76-445e-ac85-4059538dc368", "enrich_notes": "WQv uses 90th percentile rainfall depth 1.20 in (Ch. 7 example). Common SHWT separation is 2 ft (24 in); sole-source aquifer and some infiltration contexts require 4 ft (48 in). Rain gardens specify 12–18 in min filter media by variant; standard infiltration/filtration bioretention require 30 in min media. Infiltration feasibility threshold fc ≥ 0.50 in/hr; pond outlets detain WQv 24 hr (12 hr trout waters). Dry swale channel slope 0.50%–4.0% (single canonical slope value not specified).", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "youngstown-oh", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/youngstown-oh/", "data_url": "https://stormwateratlas.com/data/manuals/youngstown-oh.json", "document_metadata": { "jurisdiction_name": "City of Youngstown", "jurisdiction_level": "municipality", "state_code": "OH", "document_title": "Rainwater and Land Development — Ohio's Standards for Stormwater Management (city MS4)", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "WQv (ac-ft) = C × 0.75 × A / 12 (treat runoff from 0.75 inch of precipitation); Ohio EPA NPDES requires 20% additional WQv for sediment; extended detention drawdown 24–48 hours. Used where no durable city design-manual PDF was found (or prior extract was empty/scanned).", "peak_flow_calculation_method": [ "NRCS TR-55", "USGS empirical equations for small urban streams in Ohio", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Water Quality Ponds", "Infiltration / Filtration practices", "LID / Conservation Development", "Wetland / Stream setbacks" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Youngstown MS4 — Ohio Rainwater and Land Development standards", "page_or_section": "Coverage note" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "for construction activities. WQv (ac-ft) = C * 0.7\u0018 * A / \u00182 (Equation \u0018) Where: C = runoff coefficient A = area draining into the BMP in acres The runoff coefficient, C, is calculated using the following equation or alternatively values provided in the current Ohio EPA NP", "page_or_section": "p. 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv (ac-ft) = C * 0.75 * A / 12", "page_or_section": "CHAPTER 2, Water Quality Volume, page 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 0.75 inch precipitation depth", "page_or_section": "Bioretention Design Checklist, page 83" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "drained over a 24-48 hour period", "page_or_section": "Water Quality Volume (Applicable to all pond configurations), page 37" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain times in excess of 72 hours should be avoided", "page_or_section": "2.7 Infiltration Trench, page 51" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum 4ft of separation required between the water table and the bioretention practice", "page_or_section": "2.10 Bioretention, page 77" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "leave at least 2 feet between the seasonal high-water table or bedrock and the trench bottom", "page_or_section": "2.7 Infiltration Trench, page 51" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "ds = planting soil depth (2.5 feet minimum)", "page_or_section": "Bioretention sizing, page 84" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 48-hour period", "page_or_section": "Dry Extended Detention Basin – Outlet Design, page 40" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 24-hour period", "page_or_section": "Wet Extended Detention Basin – Outlet Design, page 41" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "length generally exceeding 2:1 (length:width)", "page_or_section": "2.10 Bioretention Area Dimensions, page 80" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "minimum drawdown time of 40 hours", "page_or_section": "2.10 Bioretention Detention, page 79" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide Ohio manual used as MS4 post-construction reference when city PDF unavailable/empty.", "fields_not_found": [] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-10T10:35:05.250Z", "original_filename": "youngstown-oh.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": 48, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:38:05.221Z", "enrich_model": "composer-2.5:run-fdf86e47-ba5a-4642-8336-3adf6eca0c0b", "enrich_notes": "Ohio EPA WQv uses 0.75 in precipitation (P) in WQv = C × 0.75 × A / 12; NPDES requires +20% WQv for sediment. General pond WQv drawdown cited as 24–48 hr; dry extended detention outlet explicitly 48 hr (<50% in first 16 hr); wet extended detention ED drawdown 24 hr (<50% in first 8 hr). Infiltration trench drain 24–48 hr (avoid >72 hr); soil K 0.5–2.5 in/hr; min 2 ft SHWT/bedrock below trench bottom (24 in). Bioretention min 40 hr drawdown (Ohio EPA); filter bed drain time 40 hr (1.66 days) in sizing; SHWT min 4 ft required (2 ft recommended); ponding generally <6 in, up to 12 in; media min 2.5 ft; min width 10 ft; L:W >2:1. Sand filter total drawdown 40 hr. Wetland pool depths 6–18 in (avg 6–12 in); wet pond permanent pool mean depth 3–6 ft (range only).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "yuma-az", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/yuma-az/", "data_url": "https://stormwateratlas.com/data/manuals/yuma-az.json", "document_metadata": { "jurisdiction_name": "City of Yuma", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Drainage Policies and Standards Manual for Maricopa County (adopted by Yuma SWMP)", "version_or_edition": "revised 11/2025", "adoption_or_effective_date": null, "last_revised_date": "2025-11", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 50, 100 ], "water_quality_volume_method": "Yuma SWMP/code adopt Maricopa County Erosion Control Drainage Design Manual and Drainage Policies as technical guidance. Maricopa Policy 3.6.6 First Flush: retain or treat the first 0.5 inches of direct runoff; Standard 6.10.2: new developments retain stormwater from a 100-year, 2-hour duration storm. City Code §192-04 retention also references 100-year 2-hour (1.22 in/hr) for residential basins.", "peak_flow_calculation_method": [ "Local 2-year, 24-hour storm peak control (Yuma §195-09)", "100-year 2-hour retention volume (Maricopa / Yuma §192-04)", "10-year 2-hour street conveyance" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention basins", "Infiltration / LID BMPs per Maricopa ECDDM", "Detention / conveyance controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City adopted Standard Construction Specifications and the Erosion Control Drainage Design Manual for Maricopa County, Arizona", "page_or_section": "Yuma SWMP BMP 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "First Flush: retain or treat the first 0.5 inches of direct runoff", "page_or_section": "Maricopa Drainage Policies 3.6.6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first flush is defined as the first one-half (1/2) inch of direct runoff from the contributing drainage basin.", "page_or_section": "Glossary, page 151" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Analysis confirming basin draining within 36 hours of the end of the design precipitation event is required.", "page_or_section": "6.14.3 Additional Report Requirements item 4, page 131" }, { "field": "practice_mentions.swale", "excerpt": "Interceptor channels (and other low impact development techniques, such as: bioswales, microbasins) may be required/needed to collect offsite flow into an onsite channel.", "page_or_section": "Section 7.2 / page 140" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "2.7.4 Pervious Concrete ... pervious concrete \"is usually part of a water management system used to reduce runoff rates and volumes from on-grade surfaces such as patios, walkways, driveways, fire lanes, and parking spaces\"", "page_or_section": "Summary of Changes 6th Edition Draft, page 195" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Yuma explicitly adopts Maricopa ECDDM/Drainage Policies; local retention rates in City Code Ch.192.", "fields_not_found": [] }, "source": { "document_url": "https://www.esd.maricopa.gov/DocumentCenter/View/2369/Drainage-Policies-and-Standards-Manual-for-Maricopa-County---revised-112025-PDF", "landing_page_url": "https://www.yumaaz.gov/", "retrieved_at": "2026-08-10T10:44:44.192Z", "original_filename": "yuma-az.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 36, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:38:34.927Z", "enrich_model": "composer-2.5:run-01ada31c-662b-4c95-a9c6-46612b27ea57", "enrich_notes": "Corpus defines First Flush as the first 0.5 inch of direct runoff (Glossary). Hydrology report checklist requires retention basin drain analysis within 36 hours after the design precipitation event. Retention basin checklist references jurisdiction-specific max depth and first-flush documentation but numeric SCM dimensions, SHWT separation, and infiltration rates are not in these excerpts (revision history references Standard 6.10.10–6.10.13 without criteria text).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "las-vegas-nv", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/las-vegas-nv/", "data_url": "https://stormwateratlas.com/data/manuals/las-vegas-nv.json", "document_metadata": { "jurisdiction_name": "Clark County Regional Flood Control District", "jurisdiction_level": "special_district", "state_code": "NV", "document_title": "Hydrologic Criteria and Drainage Design Manual (HCDDM)", "version_or_edition": null, "adoption_or_effective_date": "1999", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Regional flood control / drainage design criteria; water quality BMP sizing may be in local agency supplements. Prepared extract truncated for large HCDDM.", "peak_flow_calculation_method": [ "Minor storm: 10-year (§304.2)", "Major storm: 100-year (§304.2)", "Rainfall frequencies from 2-year through 100-year (§500)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention", "Channels", "Storm drains", "Flood control facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Clark County Regional Flood Control District", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Regional Flood Control District", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Hydrologic Criteria and Drainage Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "--- page 7 --- Adopted August 12, 1999 HYDROLOGIC CRITERIA AND DRAINAGE DESIGN MANUAL 100 CLARK COUNTY REGIONAL FLOOD CONTROL DISTRICT HYDROLOGIC CRITERIA AND DRAINAGE DESIGN MANUAL SECTION 100 GENERAL PROVISIONS TABLE OF CONTENTS Page 101 TITLE 101 102 A", "page_or_section": "p. 7" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minor storm 10-year / major storm 100-year", "page_or_section": "§304.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "minor and major storm", "page_or_section": "§304.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "drainage design", "page_or_section": "HCDDM" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "detention / channels / storm drains", "page_or_section": "Design chapters" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The MOP uses 0.37 inches for the Las Vegas Valley for the average rain fall depth", "page_or_section": "Section 1207 / page 468" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Calculations for sizing water quality capture volumes for detention basins should use the maximized detention volume calculation (per Water Environment Federation [WEF] Manual of Practice [MOP] No. 23), a 24-hr drain time", "page_or_section": "Section 1207.1 / page 468" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "EDBs should detain a WQCV for a minimum of 24 hours and up to a maximum of 48 hours", "page_or_section": "Section 1207 / page 468" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The outflow structure should be sized to allow for complete drawdown of the water quality volume in 72 hours", "page_or_section": "Section 1503.12.5 / page 575" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum infiltration or dewatering time is 72 hours", "page_or_section": "Section 1503.13.5 / page 579" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The water table should be at least 2 feet below the bottom of the trench", "page_or_section": "Section 1503.13.5 / page 578" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "For areas longer than 20 ft, the depressed landscape should be twice as long as they are wide", "page_or_section": "Section 1503.6.5 / page 551" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Tributary Area (ac) Swale Slope ≤ 0.5 ≤ 1%", "page_or_section": "Section 1503.4.5 Design Criteria / page 547" }, { "field": "practice_mentions.extended_detention", "excerpt": "incorporating extended detention basins (EDBs) within the regional detention basins", "page_or_section": "Section 1207 / page 468" }, { "field": "practice_mentions.swale", "excerpt": "Landscape swales are typically located in parks, parkways, private landscaped areas", "page_or_section": "Section 1503.4.3 / page 547" }, { "field": "practice_mentions.sand_filter", "excerpt": "tf = Design filter bed drain time or the time required for the WQCV to pass through the filter in hrs (Max: 48 hours)", "page_or_section": "Section 1500 sand filter / page 561" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "An infiltration trench is a shallow excavation (generally 2 to 10 feet in depth)", "page_or_section": "Section 1503.13.1 / page 577" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Infiltration basins are not allowed in areas of shallow groundwater or poor permeability soils", "page_or_section": "Section 1503.12.5 / page 575" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Clark County HCDDM covers Las Vegas metro flood/drainage criteria. Text extract truncated; confirm WQ BMP chapter if present. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://gustfront.ccrfcd.org/pdf_arch1/hcddm/current%20manual%20(complete)/hcddm.pdf", "landing_page_url": "https://www.regionalflood.org/", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "las-vegas-nv.pdf" }, "design_parameters": { "wqv_depth_inches": 0.37, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 1, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale" ], "enriched_at": "2026-08-13T08:56:42.753Z", "enrich_model": "composer-2.5:run-60255ebd-2a91-4f06-9cd8-8578b4d79771", "enrich_notes": "Corpus is policy/plan submittal fragments plus Section 1207 regional EDB/WQCV (MOP 23, 0.37 in Las Vegas rainfall depth, 24–48 hr EDB detention) and Section 1500 BMP excerpts. On-site dry extended detention requires full WQV drawdown in 72 hr with ≤50% in first 24 hr. Infiltration trench: 0.5 in impervious runoff volume basis, 2 ft SHWT separation, 72 hr max dewatering, 0.3 in/hr minimum obtainable rate (0.5 in/hr stated for infiltration basins). Depressed landscaping (not mapped to bioretention) gives 6–12 in ponding and L:W=2. Landscape swale table: slope ≤1%, depth max 9 in. EDB outlet guidance references Denver UDFCD (2008). Porous pavement and full infiltration basin design pages not in excerpt.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "oregon-manual", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/oregon-manual/", "data_url": "https://stormwateratlas.com/data/manuals/oregon-manual.json", "document_metadata": { "jurisdiction_name": "Clean Water Services", "jurisdiction_level": "special_district", "state_code": "OR", "document_title": "Low Impact Development Approaches Handbook", "version_or_edition": "2016", "adoption_or_effective_date": "2016-06", "last_revised_date": "2016-06", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Size LIDA facilities with District sizing factors based on the water quality design storm and typical soils (WQV rate/volume methods are in Design and Construction Standards Chapter 4). Infiltration planter/rain garden, flow-through planter, LIDA swale, and vegetated filter strip use a sizing factor of 0.06 × contributing impervious area when native infiltration is less than 2 in/hr (smaller factors allowed with demonstrated higher infiltration or deeper amended soil). Porous pavement and green roofs replace impervious area at 1:1 and may be deducted as LIDA credits. Extended dry basins and constructed water quality wetlands must accommodate the water quality design storm with 48-hour drawdown; minimum water quality detention volume equals 1 × WQV.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Porous Pavement", "Green Roof", "Infiltration Planter/Rain Garden", "Flow-Through Planter", "LIDA Swale", "Vegetated Filter Strip", "Vegetated Swale", "Extended Dry Basin", "Constructed Water Quality Wetland", "Proprietary Facility" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Clean Water Services (the District) is a water resources management utility in urban areas of the Tualatin River Watershed", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Clean Water Services (the District) is a water resources management utility in urban areas of the Tualatin River Watershed that builds, maintains and enhances the public drainage system in partnership with Washington County and its member Cities.", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "document_metadata.state_code", "excerpt": "strict water quality regulations set for the Tualatin River basin by the Oregon Department of Environmental Quality (DEQ).", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "document_metadata.document_title", "excerpt": "Low Impact Development Approaches Handbook", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Low Impact Development Approaches Handbook 2016", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "The handbook was updated in June 2016", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "document_metadata.last_revised_date", "excerpt": "The handbook was updated in June 2016", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This handbook is a supplement to the Standards and is to be used in conjunction with them and other applicable regulations.", "page_or_section": "Chapter 1: Introduction, Page 4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The water quality storm runoff rate volume calculations for sizing water quality facilities are presented in Chapter 4 of the Design and Construction Standards. ... LIDA Sizing Form ... based on the water quality design storm and typical soil conditions. ... Infiltration Planters/Rain Garden 0.06 Flow-through Planter 0.06 LIDA Swale 0.06 Vegetated Filter Strip 0.06 ... The minimum water quality detention volume is equal to (1) x the water quality volume (WQV). ... sized for a 48 hour drawdown time.", "page_or_section": "Chapter 3 §§3.1–3.2 / LIDA Sizing Form, Pages 17–19; Extended Dry Basin / Constructed Wetland fact sheets, Pages 51 & 55" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Porous Pavement ... Green Roof ... Infiltration Planter/Rain Garden ... Flow-Through Planter ... LIDA Swale ... Vegetated Filter Strip ... Vegetated Swale ... Extended Dry Basin ... Constructed Water Quality Wetland ... proprietary facility may be appropriate.", "page_or_section": "Table of Contents / Table 2: LIDA Fact Sheet Table, Pages 3 & 20–21; Chapter 3 §3.2, Page 19" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "At a minimum, the detention basin must accommodate the water quality design storm and be sized for a 48 hour drawdown time.", "page_or_section": "Extended Dry Basin Design Factors, page 51" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Dry Basin ... 2-cell design, 48-hour draw-down", "page_or_section": "Table 2, page 20" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "be sized for a 48 hour drawdown time", "page_or_section": "Constructed Water Quality Wetland Design Factors, page 55" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "seasonal high water table is at least 10 feet beneath the facility's bottom or drain rock layer", "page_or_section": "Porous Pavement Application & Limitations, page 22" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Diagram labels 3\" (ponding zone above growing medium)", "page_or_section": "Infiltration Planter/Rain Garden, page 30" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Growing medium ... 9\"", "page_or_section": "Infiltration Planter/Rain Garden diagram, page 30" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The minimum width of the bottom of the extended dry basin is 4 feet, and the permanent pool depth is 0.4 feet and covers the entire bottom of the basin.", "page_or_section": "Extended Dry Basin Geometry/Slopes, page 51" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "a maximum 6-inch layer of soil", "page_or_section": "Glossary eco-roof, page 68" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "green roof technology, for roofs with 1:3 pitch or flatter", "page_or_section": "Table 2 / Green Roof fact sheet, page 20" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Handbook is a supplement to Clean Water Services Design and Construction Standards; water quality design storm rainfall depth/intensity and peak-flow hydrology methods are deferred to Standards Chapter 4 and are not specified here. Only freeboard references a 25-year water surface elevation for extended dry basins and wetlands.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.canbyoregon.gov/sites/default/files/fileattachments/streets_and_sewer/page/6341/cws_low_impact_development_lid.pdf", "landing_page_url": "https://cleanwaterservices.org/development/dnc/lida/", "retrieved_at": "2026-08-10T07:09:00.000Z", "original_filename": "oregon-manual.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": 9, "bioretention_ponding_depth_inches": 3, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 4.8, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 6, "green_roof_slope_percent": 33.33, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:35:01.256Z", "enrich_model": "composer-2.5:run-01b5063b-de4b-413f-ad22-6a13fda6a69b", "enrich_notes": "Handbook defers WQV rainfall depth and hydrology to Clean Water Services Design and Construction Standards Chapter 4. LIDA sizing uses 0.06× contributing impervious area for infiltration planters, flow-through planters, LIDA swales, and vegetated filter strips when native infiltration is assumed <2 in/hr. Porous pavement and green roofs are 1:1 impervious credits. Extended dry basins and constructed water quality wetlands require minimum detention volume of 1×WQV with 48-hour drawdown; orifice sizing uses Q=WQV/(48×60×60). Infiltration planter diagram labels 3 in ponding and 9 in growing medium; porous pavement requires SHWT ≥10 ft below bottom/drain rock. Glossary cites max 6 in eco-roof soil; green roof fact sheet allows roofs at 1:3 pitch or flatter.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "mtd_verification_program" ] } }, { "slug": "savannah-ga-css", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/savannah-ga-css/", "data_url": "https://stormwateratlas.com/data/manuals/savannah-ga-css.json", "document_metadata": { "jurisdiction_name": "Coastal Georgia (Chatham County–Savannah region)", "jurisdiction_level": "other", "state_code": "GA", "document_title": "Coastal Stormwater Supplement to the Georgia Stormwater Management Manual", "version_or_edition": "First Edition, April 2009", "adoption_or_effective_date": "2009-04", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Runoff Reduction Volume (RRv) for the 85th percentile / first-flush event: reduce runoff from the 1.2-inch rainfall event (and the first 1.2 inches of larger events); RRv = (1.2 in.)(Rv)(A)/12 with Rv = 0.05 + 0.009(I). Within 1/2-mile of shellfish harvesting areas, target is the 90th percentile / 1.5-inch event. Remaining unreduced 1.2-inch runoff must be treated in practices providing ≥80% TSS reduction and reducing nitrogen and bacteria to the MEP. Aquatic Resource Protection Volume (ARPv): 24 hours extended detention of the 1-year, 24-hour storm.", "peak_flow_calculation_method": [ "SCS Runoff Curve Number Method (NRCS, 1986)", "Modified Graphical Peak Discharge and Storage Volume Estimation Methods from TR-55 (NRCS, 1986)", "NRCS (SCS) unit peak discharge / Type II and Type III rainfall distributions" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Soil Restoration", "Site Reforestation/Revegetation", "Green Roofs", "Permeable Pavements", "Undisturbed Pervious Areas", "Vegetated Filter Strips", "Grass Channels", "Simple Downspout Disconnection", "Rain Gardens", "Stormwater Planters", "Dry Wells", "Rainwater Harvesting", "Bioretention Areas", "Infiltration Practices", "Dry Swales", "Stormwater Ponds", "Stormwater Wetlands", "Filtration Practices", "Swales", "Dry Detention Basins" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The development of this Coastal Stormwater Supplement was facilitated by the Chatham County-Savannah Metropolitan Planning Commission... cities and counties of coastal Georgia.", "page_or_section": "Title / Acknowledgments" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Counties included within Georgia's Coastal Nonpoint Source Management Area include: Bryan, Brantley, Camden, Charlton, Chatham, Effingham, Glynn, Liberty, Long, McIntosh and Wayne.", "page_or_section": "Section 1.2" }, { "field": "document_metadata.state_code", "excerpt": "Georgia Coastal Stormwater Supplement April 2009", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Coastal Stormwater Supplement to the Georgia Stormwater Management Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "First Edition April 2009", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This monitoring protocol provides information that can be used to evaluate the performance of green infrastructure and stormwater management practices in coastal Georgia. The protocol presents a simple, yet comprehensive monitoring approach that can be used to accurately ev", "page_or_section": "p. 493" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "providing 24 hours of extended detention for the stormwater runoff volume generated by the 1-year, 24-hour storm event", "page_or_section": "Table 4.5 / SWM Criteria #3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "controlling (attenuating) the peak discharge generated by the 25-year, 24-hour storm event under post-development conditions.", "page_or_section": "Table 4.5 / SWM Criteria #4 Overbank Flood Protection" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "controlling (attenuating) the peak discharge generated by the 100-year, 24-hour storm event under post-development conditions.", "page_or_section": "Table 4.5 / SWM Criteria #5 Extreme Flood Protection" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "storm events that are smaller than the 25-year, 24-hour storm event and larger than the 1-year, 24-hour storm event (e.g., 2-year, 24-hour storm event, 10-year, 24-hour storm event).", "page_or_section": "Section 4.4.4 Overbank Flood Protection" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "In coastal Georgia, this equates to reducing the stormwater runoff volume generated by the 1.2 inch rainfall event (and the stormwater runoff generated by the first 1.2 inches of all larger rainfall events).", "page_or_section": "Table 4.5 / SWM Criteria #1 Stormwater Runoff Reduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "it should be intercepted and treated in one or more stormwater management practices that: (1) provide for at least an 80 percent reduction in TSS loads; and (2) reduce nitrogen and bacteria loads to the maximum extent practical.", "page_or_section": "Table 4.5 / SWM Criteria #2 Stormwater Quality Protection" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "24 hours of extended detention be provided for the stormwater runoff volume generated by the 1-year, 24-hour storm event... aquatic resource protection volume (ARPv)", "page_or_section": "Section 4.4.3 SWM Criteria #3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "modified version of the Graphical Peak Discharge and Storage Volume Estimation Methods presented in Technical Release 55 (TR-55) (NRCS, 1986).", "page_or_section": "Section 5.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The SCS Runoff Curve Number Method (NRCS, 1986) uses a combination of these factors to assign a runoff curve number", "page_or_section": "Section 5.4.2 Step 2" }, { "field": "design_parameters.practice_mentions.bioretention", "excerpt": "Complex Monitoring Situation (e.g., bioretention areas, dry swales)", "page_or_section": "Appendix C, Table C.4, page 498" }, { "field": "design_parameters.practice_mentions.wet_pond", "excerpt": "Simple Monitoring Situation (e.g., wet pond)", "page_or_section": "Appendix C, Table C.4, page 498" }, { "field": "design_parameters.practice_mentions.swale", "excerpt": "Complex Monitoring Situation (e.g., bioretention areas, dry swales)", "page_or_section": "Appendix C, Table C.4, page 498" }, { "field": "design_parameters.practice_mentions.green_roof", "excerpt": "Nonstructural stormwater management practices include, but are not limited to, ... green roofs, vegetated filter strips and rain gardens.", "page_or_section": "Appendix D, Section 2.0 Definitions, page 520" }, { "field": "design_parameters.practice_mentions.extended_detention", "excerpt": "“Extended Detention” means the temporary storage of stormwater runoff in a stormwater management practice for an extended period of time, typically 24 hours or greater.", "page_or_section": "Appendix D, Section 2.0 Definitions, page 518" }, { "field": "design_parameters.practice_mentions.infiltration_basin", "excerpt": "several groups of green infrastructure and stormwater management practices are not well represented in either of them, including bioretention areas, infiltration practices", "page_or_section": "Appendix C, C.1 Introduction, page 493" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Regional coastal Georgia supplement (facilitated by Chatham County–Savannah MPC), not a City of Savannah ordinance. Jurisdiction level coded as other because the CSS applies across the multi-county Coastal NPS Management Area and Area of Special Interest. Supplements the Georgia Stormwater Management Manual (GSMM); CSS controls on conflict—schema has no 'supplements' enum so relationship_to_state_manual is independent. Pipeline excerpt repair removed 5 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.adoption_or_effective_date", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/Georgia-CSS-Final-Apr-09.pdf", "landing_page_url": "https://epd.georgia.gov/watershed-protection-branch/storm-water/georgia-epd-coastal-stormwater-supplement-stormwater", "retrieved_at": "2026-08-08T10:41:49.492Z", "original_filename": "savannah-ga-css.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:06:07.317Z", "enrich_model": "composer-2.5:run-319583a2-9467-4e78-a015-ebd74847b8be", "enrich_notes": "Provided corpus is Appendix A habitat table, Appendix C monitoring protocol, and Appendix D model ordinance—not BMP design chapters. Runoff reduction and treatment criteria reference the CSS/GSMM by edition without restating rainfall depths or facility dimensions in these excerpts. Extended Detention is defined qualitatively (storage for an extended period, typically 24 hours or greater) without a mandated drawdown rate for a specific SCM.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "co-cwcb-floodplain-stormwater", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/co-cwcb-floodplain-stormwater/", "data_url": "https://stormwateratlas.com/data/manuals/co-cwcb-floodplain-stormwater.json", "document_metadata": { "jurisdiction_name": "Colorado", "jurisdiction_level": "state", "state_code": "CO", "document_title": "CWCB Floodplain and Stormwater Criteria Manual Ch15 Storm Drainage Water Quality", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Extended Detention", "Sand Filter", "Constructed Wetland", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "CWCB Floodplain and Stormwater Criteria Manual Ch15 Storm Drainage Water Quality", "page_or_section": "Title / header" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Extended Detention, Sand Filter, Constructed Wetland", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water quality facilities that provide runoff storage volume for a “water quality capture volume” (WQCV) (ASCE/WEF 1998 and UDFCD 1999) should be required or encouraged", "page_or_section": "CH15-103 / 1.3 GENERAL CRITERIA, page 4" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain times of 12 to 48 hours, depending on the type of BMP selected, are recommended by many of the most common technical references and criteria manuals.", "page_or_section": "CH15-104 / item 3, page 5" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Drain times of 12 to 48 hours, depending on the type of BMP selected, are recommended by many of the most common technical references and criteria manuals.", "page_or_section": "CH15-104 / item 3, page 5" }, { "field": "practice_mentions.extended_detention", "excerpt": "1. Extended detention basin 2. Sand filter extended detention basin 3. Constructed wetland basin 4. Retention pond", "page_or_section": "2.4.5 DETENTION BASIN, page 17" }, { "field": "practice_mentions.sand_filter", "excerpt": "Sand filter extended detention basin", "page_or_section": "2.4.5 DETENTION BASIN, page 17" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "For sites with sufficient water to support wetlands, detention facilities can be developed as a constructed wetland basin.", "page_or_section": "2.4.6 CONSTRUCTED WETLANDS, page 18" }, { "field": "practice_mentions.wet_pond", "excerpt": "4. Retention pond", "page_or_section": "2.4.5 DETENTION BASIN, page 17" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous pavement detention is flat and includes a shallow storage area above the surface for the water quality capture volume (WQCV).", "page_or_section": "2.4.3 POROUS PAVEMENT, page 15" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "includes a shallow storage area above the surface for the water quality capture volume (WQCV)", "page_or_section": "2.4.3 POROUS PAVEMENT, page 15" }, { "field": "practice_mentions.bioretention", "excerpt": "Examples of LID “integrated management practices” include bioretention, permeable pavers, tree box planters, rain gardens, and disconnected downspouts.", "page_or_section": "2.3 SITE DESIGN PRACTICES, page 12" }, { "field": "practice_mentions.green_roof", "excerpt": "Typical Applications: Parking islands, medians and buffers, courtyards, planters, and green roofs.", "page_or_section": "2.4.4 POROUS LANDSCAPE DETENTION, page 16" }, { "field": "practice_mentions.swale", "excerpt": "If flow can be conveyed on the surface in grass swales or in strips of modular block porous pavement, additional stormwater quality benefits will accrue", "page_or_section": "1.5 DESIGN PRINCIPLES AND PROCESS, page 7" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "2.4.7 UNDERGROUND FACILITIES/PROPRIETARY DEVICES", "page_or_section": "Section 2 BMP TOC, page 10" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. CWCB Floodplain and Stormwater Criteria Manual Ch15 Storm Drainage Water Quality (statewide DNR; CDPHE is permit-only) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://dnrweblink.state.co.us/CWCB/0/edoc/211428/Chapter%2015.pdf", "landing_page_url": "https://cwcb.colorado.gov/public-information/technical-tools/floodplain-stormwater-criteria-manual", "retrieved_at": "2026-08-11T17:59:10.610Z", "original_filename": "co-cwcb-floodplain-stormwater.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:55:26.023Z", "enrich_model": "composer-2.5:run-4903aadb-95bb-4109-a774-a5b16e152178", "enrich_notes": "Chapter 15 is a statewide overview; numeric sizing is deferred to local criteria and references (especially UDFCD 1999 Volume 3-BMP and Denver WQMP 2004). WQCV is required or encouraged but no rainfall depth in inches is stated. Timed-release outlets should treat WQCV; drain times of 12–48 hours are cited as recommendations from common references, not as a single mandated maximum or ED-specific value. Detention basin types listed: extended detention, sand filter extended detention, constructed wetland, retention pond. Sites under one acre directed to porous landscape detention and porous pavement detention; basins generally for areas greater than one acre. Porous pavement detention includes shallow surface storage for WQCV without a depth in inches. Porous landscape detention mentions a three-foot tree radius exclusion (landscape rule, not a listed extraction field). Safety: railing at vertical drops of 30 inches or more; retaining walls over 30 inches require handrails (IBC).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ct-ctdot-drainage", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/ct-ctdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ct-ctdot-drainage.json", "document_metadata": { "jurisdiction_name": "Connecticut", "jurisdiction_level": "state", "state_code": "CT", "document_title": "CTDOT Drainage Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Pond", "Dry Pond", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "CTDOT Drainage Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "loodplain. • The predicted value of the 100-year or base flood serves as the present engineering standard for evaluating flood h", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ccurs in the future; • documenting that rationally accepted procedures and analysis were used at the time of the design which we", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wet Pond, Dry Pond, Detention Basin", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the recommended WQV... is equivalent to the runoff associated with the first one-inch of rainfall", "page_or_section": "10.11.3 / page 551" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = design precipitation, inches (1\" for water quality storm)", "page_or_section": "Appendix 11.C / page 673" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The WQV should be detained and released over a period of 24 h.", "page_or_section": "10.11.3 / page 551" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "there should be at least 1.5 m (5 ft) between the bottom of the facility to the seasonable high water table", "page_or_section": "10.13.1 / page 562" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rates of greater than 25 mm/h (1 in/h) are preferred for infiltration facilities.", "page_or_section": "10.13.2 / page 563" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A maximum detention time of 72 h is recommended.", "page_or_section": "10.13.3 / page 566" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Basin depth should be between 1.5 and 3.0 m (5 and 10 ft)", "page_or_section": "10.12.3 / page 557" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The length-to-width ratio should be at least 3:1.", "page_or_section": "10.12.3 / page 557" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. CTDOT Drainage Manual — full PDF Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://portal.ct.gov/dot/-/media/dot/drainage/ctdot-drainage-full-pdf.pdf", "landing_page_url": "https://portal.ct.gov/dot/bureaus/engineering-and-construction/engineering/facilities-and-transit/soils-foundation-hydraulics-and-drainage", "retrieved_at": "2026-08-11T17:59:10.530Z", "original_filename": "ct-ctdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 1, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 24, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:00:07.044Z", "enrich_model": "composer-2.5:run-f17f6d0e-708c-4101-9873-57244d0496b7", "enrich_notes": "WQV follows Connecticut Stormwater Quality Manual first-inch runoff; CTDOT routes WQV with 24 h release for detention basins. Infiltration BMPs require 5 ft to SHWT/bedrock; WQV infiltrate within 48 h (trenches/basins); trench max detention 72 h. Wet detention permanent pool 5–10 ft depth, L:W ≥3:1. Minimum preferred infiltration 1 in/h; subsoil exfiltration figure cites 7 mm/h. Quantity control: 2-, 10-, 25-year peaks to predevelopment; pass 100-year.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ct-state", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/ct-state/", "data_url": "https://stormwateratlas.com/data/manuals/ct-state.json", "document_metadata": { "jurisdiction_name": "Connecticut", "jurisdiction_level": "state", "state_code": "CT", "document_title": "Connecticut Stormwater Quality Manual", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-03-30", "last_revised_date": "2024-03-26", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV = (P)(R)(A)/12 where P = 1.3 inches (90th percentile rainfall event), R = volumetric runoff coefficient = 0.05 + 0.009(I) where I is the post-development impervious area percentage, and A is the drainage area in square feet.", "peak_flow_calculation_method": [ "NRCS Curve Number method", "Graphical Peak Discharge Method", "TR-20", "Rational Formula" ], "required_hydrologic_hydraulic_software": [ "WinTR-55", "HydroCAD", "TR-20", "Hantush Groundwater Mounding Spreadsheet" ], "approved_bmp_categories": [ "Pretreatment BMPs", "Infiltration BMPs", "Filtering BMPs", "Stormwater Pond BMPs", "Stormwater Wetland BMPs", "Water Quality Conveyance BMPs", "Stormwater Reuse BMPs", "Proprietary BMPs", "Other BMPs and BMP Accessories" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Connecticut Stormwater Quality Manual", "page_or_section": "Cover Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "CONNECTICUT DEPARTMENT OF ENERGY & ENVIRONMENTAL PROTECTION", "page_or_section": "Cover Page" }, { "field": "document_metadata.document_title", "excerpt": "Connecticut Stormwater Quality Manual", "page_or_section": "Cover Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Latest Revision March 26, 2024", "page_or_section": "Cover Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective Date: March 30, 2024", "page_or_section": "Cover Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Latest Revision March 26, 2024", "page_or_section": "Cover Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "CONNECTICUT DEPARTMENT OF ENERGY & ENVIRONMENTAL PROTECTION", "page_or_section": "Cover Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Control the 2-year, 24-hour post-development peak flow rate... Control the 10-year, 24-hour post-development peak flow rate... Potentially control the 100-year, 24-hour post-development peak flow rate", "page_or_section": "Page 35, Table 4-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P)(R)(A)/12 where: WQV = water quality volume (cubic feet) P = 1.3 inches (90th percentile rainfall event) R = volumetric runoff coefficient = 0.05+0.009(I) I = post- development impervious area (percent) A = post-development total drainage area of site or design point (square feet)", "page_or_section": "Page 46, Water Quality Volume Calculation" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "using a hydrologic/hydraulic routing model based on the NRCS Curve Number method (e.g., HydroCAD or similar software)... Graphical Peak Discharge Method... routing employed by TR-20... Rational Formula", "page_or_section": "Page 59, Appendix D" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "hydrologic analysis software such as WinTR-55... HydroCAD or similar software... TR-20... USGS and New Jersey Department of Environmental Protection Hantush Groundwater Mounding Spreadsheet", "page_or_section": "Page 55, 59, 190" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "This Manual includes the following major categories and types of structural stormwater BMPs that are recommended for use in Connecticut, based on their primary function: Pretreatment BMPs, Infiltration BMPs, Filtering BMPs, Stormwater Pond BMPs, Stormwater Wetland BMPs, Water Quality Conveyance BMPs, Stormwater Reuse BMPs, Proprietary BMPs, Other BMPs and BMP Accessories", "page_or_section": "Page 110-111, Functional Categories of Structural Stormwater BMPs" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.3 inches (90th percentile rainfall event)", "page_or_section": "Chapter 4, page 53" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention system should completely drain in 48 hours or less after the end of the design storm", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "For infiltration systems, at least 3 feet of separation is recommended", "page_or_section": "Chapter 10, page 194" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered bioretention soil media should have a depth of 24 to 48 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for water quality storm: 12 inches", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "0.5 inches per hour (1.0 feet per day) for the bioretention soil media, whichever value is lower", "page_or_section": "Chapter 13 – Bioretention, page 320" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The detention basin should completely drain within 48 hours after the end of a storm", "page_or_section": "Chapter 13 – Dry Extended Detention Basin, page 467" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom Width Minimum: 2 feet", "page_or_section": "Chapter 13 – Wet Water Quality Swale, page 421" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "BMPs such as water quality swales and permeable pavement is restricted to slopes of approximately 5% or less", "page_or_section": "Chapter 8, page 135" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "Green Roof Ground Slope Not Applicable (max 20% roof slope)", "page_or_section": "Table 8-3, page 140" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "The document is the official Connecticut Stormwater Quality Manual, and all details, including the updated 1.3-inch water quality storm and NOAA Atlas 14 storm return periods, were extracted directly with matching exact citations. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.state_code" ] }, "source": { "document_url": "https://portal.ct.gov/-/media/deep/water/water_quality_management/guidance/swm_mar_2024.pdf", "landing_page_url": "https://portal.ct.gov/DEEP/Water-Regulating-and-Discharges/Stormwater/Stormwater-Manual", "retrieved_at": "2026-08-07T11:22:12.135Z", "original_filename": "ct-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1.3, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 20, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:00:42.354Z", "enrich_model": "composer-2.5:run-318ae098-e9a9-4150-985a-7fa3a8ae15a0", "enrich_notes": "WQV uses P=1.3 in (90th percentile); runoff coefficient R=0.05+0.009(I). Infiltration suitability threshold 0.3 in/hr (HSG A/B); pretreatment required if soil infiltration >8.3 in/hr. SHGT: 36 in (3 ft) recommended below infiltration system bottom; reducible to 24 in (2 ft) in limited cases; unlined filtering systems min 12 in (1 ft) above SHGT. QPA requires ≥18 in depth to SHGT. Bioretention trees min 30 in media depth; media design permeability 0.5 in/hr (1.0 ft/day). ED basins require ≥24 h detention storage; full drawdown ≤48 h. Table 8-7 notes >48 h extended detention for bacteria at ponds/wetlands—not assigned to wetland_detention_hours.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "cook-county-il", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/cook-county-il/", "data_url": "https://stormwateratlas.com/data/manuals/cook-county-il.json", "document_metadata": { "jurisdiction_name": "Cook County", "jurisdiction_level": "county", "state_code": "IL", "document_title": "Technical Guidance Manual for the Implementation of the Watershed Management Ordinance", "version_or_edition": "MWRD TGM (compiled articles; Article 5 stormwater)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Volume control storage equals one (1) inch of stormwater runoff from newly developed impervious surfaces, treated using retention-based volume control practices first, then flow-through practices for any untreated portion. Site detention release rate must not exceed existing runoff rate (or calculated allowable release rate, whichever is smaller). Volume control storage may credit against required site detention volume.", "peak_flow_calculation_method": [ "Existing vs proposed runoff comparison (no increase)", "Site detention with allowable release rate", "Curve number method (CN tables in TGM)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention-based volume control practices", "Flow-through practices (vegetated swales, filter strips, oil/grit separators)", "Site detention facilities", "Erosion and sediment control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "management of stormwater, floodplains, wetlands, and sewer construction for developments in Cook County", "page_or_section": "TGM Introduction" }, { "field": "document_metadata.state_code", "excerpt": "Metropolitan Water Reclamation District of Greater Chicago", "page_or_section": "TGM Introduction" }, { "field": "document_metadata.document_title", "excerpt": "TECHNICAL GUIDANCE MANUAL FOR THE IMPLEMENTATION OF THE WATERSHED MANAGEMENT ORDINANCE", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Technical Guidance Manual", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Watershed Management Ordinance (WMO) ... Cook County", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "requires that one (1) inch of stormwater runoff from all impervious surfaces of the development be treated using volume control practices", "page_or_section": "Article 5 — Site Volume Control Requirements" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "allowable release rate from the site shall be either equal to or less than the existing runoff rate", "page_or_section": "Article 5 — Site Stormwater Management" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "For mechanical flow-through practices, such as an oil and grit separator, an effective maintenance plan is based on performing frequent inspections. The rate at which these devices collect pollutants will vary from site to site, and therefore frequent inspections (onc", "page_or_section": "p. 413" }, { "field": "practice_mentions.swale", "excerpt": "For grassed swales that serve as overland flow routes, regular mowing should be performed to keep grass at an optimum height (less than six inches).", "page_or_section": "Article 7 Maintenance, pages 412-412 (c0048)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Without proper maintenance, the void spaces in porous pavement and infiltration basins may become clogged with sediment, reducing their effectiveness.", "page_or_section": "Article 7 Maintenance, pages 413-413 (c0049)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Without proper maintenance, the void spaces in porous pavement and infiltration basins may become clogged with sediment, reducing their effectiveness.", "page_or_section": "Article 7 Maintenance, pages 413-413 (c0049)" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "For infiltration trenches and basins, the use of a mulch layer above the infiltration practice will work like a filter for the sediment transported by stormwater runoff.", "page_or_section": "Article 7 Maintenance, pages 413-413 (c0049)" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "For mechanical flow-through practices, such as an oil and grit separator, an effective maintenance plan is based on performing frequent inspections.", "page_or_section": "Article 7 Maintenance, pages 413-413 (c0049)" }, { "field": "practice_mentions.bioretention", "excerpt": "The letter will encourage the property owner to correct the condition and will provide information about the Village's cost-sharing programs for lateral rehabilitation, sump repair and installation, rain garden construction, and storm sewer extension.", "page_or_section": "Appendix D Sample PSP, pages 509-509 (c0108)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Extracted from MWRD TGM PDF (538 pages; text truncated/encoding degraded for some symbols). Criteria focus on Article 5 volume control (1 inch) and detention release-rate matching. WMO amendments after TGM compile may add detail. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level" ] }, "source": { "document_url": "https://mwrd.org/sites/default/files/documents/TGM.pdf", "landing_page_url": "https://mwrd.org/doing-business/watershed-management-ordinance-and-infiltrationinflow/watershed-management-ordinance-wmo-and-technical-guidance-manual-tgm/technical-guidance-manual-tgm", "retrieved_at": "2026-08-10T09:19:00.000Z", "original_filename": "cook-county-il.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:59:16.198Z", "enrich_model": "composer-2.5:run-b3a09755-37fd-44df-9cad-f2595a0ac126", "enrich_notes": "Provided corpus excerpts cover Article 6 I/I control, LTOMP/PSP, and Article 7 maintenance—not Article 5 volume-control sizing criteria. BMP types appear mainly in maintenance narrative (porous pavement, infiltration basins/trenches, grassed swales, oil/grit separators). No explicit numeric SCM design parameters (WQv depth, drawdown, media depths, infiltration rates, etc.) in these pages. Monitoring-well spacing for volume control facilities references a numeric interval but text is encoding-corrupted in excerpt.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "los-angeles-ca", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/los-angeles-ca/", "data_url": "https://stormwateratlas.com/data/manuals/los-angeles-ca.json", "document_metadata": { "jurisdiction_name": "County of Los Angeles", "jurisdiction_level": "county", "state_code": "CA", "document_title": "Low Impact Development Standards Manual", "version_or_edition": "2025", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50 ], "water_quality_volume_method": "Stormwater Quality Design Volume (SWQDv) from the greater of the 0.75-inch, 24-hour rain event or the 85th percentile, 24-hour rain event (LA County 85th percentile isohyetal map); Priority Development Projects must retain 100% of SWQDv on-site via infiltration, bioretention, and/or rainfall harvest and use. Flow-based alternative sizing: 0.2 in/hr intensity or 85th percentile hourly intensity × 2.", "peak_flow_calculation_method": [ "MODRAT (Modified Rational Method)", "Rational equation (Q = Cd × I × A)" ], "required_hydrologic_hydraulic_software": [ "HydroCalc", "HEC-RAS" ], "approved_bmp_categories": [ "Bioretention (RET-1)", "Infiltration Basin (RET-2)", "Infiltration Trench (RET-3)", "Dry Well (RET-4)", "Permeable Pavement without an Underdrain (RET-5)", "Rain Barrel/Cistern (RET-6)", "Biofiltration (BIO-1)", "Stormwater Planter (VEG-1)", "Tree-well Filter (VEG-2)", "Vegetated Swales (VEG-3)", "Vegetated Filter Strip (VEG-4)", "Sand Filters (T-1)", "Constructed Wetlands (T-2)", "Extended Detention Basin (T-3)", "Wet Pond (T-4)", "Permeable Pavement with an Underdrain (T-5)", "Proprietary Treatment Control Measures (T-6)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The County of Los Angeles (County) has prepared this 2025 Low Impact Development (LID) Standards Manual", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "guidance for the implementation of stormwater quality control measures in new development and redevelopment projects in unincorporated areas of the County", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "watersheds of Los Angeles and Ventura Counties (CAS004004, Order No. R4-2021-0105)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.document_title", "excerpt": "Low Impact Development Standards Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "This 2025 LID Standards Manual is an update of the 2014 LID Standards Manual", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The 2025 LID Standards Manual supersedes the 2014 LID Standards Manual and addresses the following objectives and goals", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "project applicants must conduct hydrology and hydraulic frequency analyses for LID, 2-, 5-, 10-, 25-, and 50-year storm events per the LACPW Hydraulic and Hydrology manuals", "page_or_section": "Section 8.3, Page 8-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The design storm, from which the SWQDv is calculated, is defined as the greater of the following: The 0.75-inch, 24-hour rain event; The 85th percentile, 24-hour rain event as determined from the Los Angeles County 85th percentile precipitation isohyetal map", "page_or_section": "Section 6.2, Page 6-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All Priority Development Projects must retain 100 percent of the SWQDv on-site through infiltration, bioretention, rainfall harvest and use, or a combination thereof", "page_or_section": "Section 2.2 / Section 7" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The maximum flow rate of runoff produced from a rainfall intensity of 0.2 inch of rainfall per hour, for each hour of a storm event; or The maximum flow rate of runoff produced by the 85th percentile hourly rainfall intensity ... multiplied by a factor of two", "page_or_section": "Section 7.5, Page 7-16" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The volume of stormwater runoff that must be retained at a project site is calculated using MODRAT", "page_or_section": "Section 6.2, Page 6-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Calculate the peak flow rate using the rational equation: Q = Cd × I × A", "page_or_section": "Section 6.2.6, Page 6-3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "LACPW developed a hydrologic calculator (HydroCalc)... Use of this program is encouraged", "page_or_section": "Section 6.3, Page 6-3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "analyze changes in flow velocity, flow volume, and depth/width of flow for all natural drainage systems using HEC-RAS", "page_or_section": "Section 8.3, Page 8-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention-based stormwater quality control measures (RET-1 to RET-6); Biofiltration (BIO-1); Vegetation-based stormwater quality control measures (VEG-1 to VEG-4); Treatment based-stormwater quality control measures (T-1 to T-6)", "page_or_section": "Section 7.2, Page 7-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention (RET-1)... Infiltration Basin (RET-2)... Infiltration Trench (RET-3)... Dry Well (RET-4)... Permeable Pavement without an Underdrain (RET-5)... Rain Barrel/Cistern (RET-6)... Biofiltration (BIO-1)... Stormwater Planter (VEG-1)... Tree-well Filter (VEG-2)... Vegetated Swales (VEG-3)... Vegetated Filter Strip (VEG-4)... Sand Filters (T-1)... Constructed Wetlands (T-2)... Extended Detention Basin (T-3)... Wet Pond (T-4)... Permeable Pavement with an Underdrain (T-5)... Proprietary Treatment Control Measures (T-6)", "page_or_section": "Table 7-1, Pages 7-3–7-4" }, { "field": "fields_not_found", "excerpt": "may preclude infiltration if less than 5 to 10 feet of separation exists between the infiltration surface and the seasonal high groundwater", "page_or_section": "p23" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention areas must completely drain within 96 hours.", "page_or_section": "Appendix D RET-1, D-6" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The base of the gravel drainage layer should have no slope and a maximum drawdown time of 96 hours.", "page_or_section": "Appendix D RET-1 Geometry, D-4" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The planting soil depth must be a minimum of two feet, but three feet is preferred.", "page_or_section": "Appendix D RET-1 Geometry, D-4" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Bioretention areas must be sized to capture and retain the SWQDv with an 18-inch maximum ponding depth.", "page_or_section": "Appendix D RET-1 Geometry, D-4" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The sediment forebay must be designed with a minimum length-to-width ratio of 2:1", "page_or_section": "Appendix D RET-2 Geometry, D-17" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "The minimum width of the vegetated swale bottom is two feet to allow for ease of mowing.", "page_or_section": "Appendix D VEG-3 Geometry, D-87" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "County (unincorporated LA) 2025 LID Standards Manual. SWQDv and retention hierarchy are explicit. Page footers say March 2026; no single ordinance effective date found in extracted text. 100-year storms referenced elsewhere for receiving-water exemptions, not as SWQDv design storms.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://dpw.lacounty.gov/ldd/lddservices/docs/Low_Impact_Development_Standards_Manual.pdf", "landing_page_url": "https://dpw.lacounty.gov/ldd/lddservices/LidIntro.htm", "retrieved_at": "2026-08-08T10:35:19.381Z", "original_filename": "los-angeles-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:00:11.039Z", "enrich_model": "composer-2.5:run-43ae97e9-3bbb-4e02-b718-c3d8ee85ac94", "enrich_notes": "SWQDv sizing referenced in Section 6 (not in excerpts). Retention BMPs require corrected in-situ infiltration ≥0.3 in/hr (GMED GS 200.1); design fdesign is site-specific. Groundwater: 5–10 ft separation range cited for infiltration feasibility; ED basins require basin bottom ≥2 ft above seasonal high groundwater. Biofiltration appendix example uses max ponding 1.5 ft and 96 hr drawdown limit. Proprietary devices require LACPW approval only—no named third-party verification program in text.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "orange-county-ca", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/orange-county-ca/", "data_url": "https://stormwateratlas.com/data/manuals/orange-county-ca.json", "document_metadata": { "jurisdiction_name": "County of Orange", "jurisdiction_level": "county", "state_code": "CA", "document_title": "Orange County Local Drainage Manual", "version_or_edition": "2nd Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Local detention basins chapter includes water quality & hydromodification considerations (7.2.10). Manual focuses on local drainage (tributary ≤640 acres); larger facilities per OCFCD Design Manual. Does not supersede Orange County DAMP.", "peak_flow_calculation_method": [ "Local drainage facility hydraulic design (Chapters 3–9)", "Detention routing analysis procedures", "100-year floodplain procedures (Chapter 11)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Local detention basins", "Vegetated swales (water quality example)", "Storm drains and local drainage structures" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "County of Orange / Orange County Local Drainage Manual", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "unincorporated Orange County", "page_or_section": "Purpose" }, { "field": "document_metadata.state_code", "excerpt": "Porter-Cologne Water Quality Control Act", "page_or_section": "Section 1.6.3" }, { "field": "document_metadata.document_title", "excerpt": "Orange County Local Drainage Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Orange County Drainage Area Management Plan (DAMP)", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year Floodplain", "page_or_section": "Section 11.3.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality & Hydromodification Considerations", "page_or_section": "Section 7.2.10" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Design Procedure - Detention Routing Analysis", "page_or_section": "Chapter 7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Local Detention Basins / Water Quality Vegetated Swale", "page_or_section": "Chapter 7 / Figure 6-9" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "the maximum bed slope should not be more than 6 percent, unless check dams are used", "page_or_section": "Chapter 6 – Open Channels, 6.4.2.3.2 Water Quality Vegetated Swales (page 6-12)" }, { "field": "practice_mentions.swale", "excerpt": "water quality vegetated swales are designed in accordance with the Water Quality Management Plan (WQMP) Technical Guidance Document (TGD)", "page_or_section": "Chapter 6, 6.4.2.3.2" }, { "field": "practice_mentions.extended_detention", "excerpt": "Perforated risers are a special case of orifice flow that can be used to obtain extended detention times.", "page_or_section": "Chapter 7 – Local Detention Basins, 7.4.3.7 (page 7-21)" }, { "field": "practice_mentions.wet_pond", "excerpt": "the water quality retention volume (e.g., volume for infiltration and wet pond volume) shall be provided in addition to the volume designated for flood storage", "page_or_section": "Chapter 7, 7.2.8 Conjunctive Use of Detention Facilities (page 7-9)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "OC Local Drainage Manual is hydraulics-focused; post-construction LID/WQ primarily in OC DAMP/TGD — consider adding TGD next. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://pwip.oc.gov/sites/ocpwocip/files/2021-08/OC%20LDM%20-%202nd%20Edition-secured.pdf", "landing_page_url": "https://ocpublicworks.com/", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "orange-county-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 6, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:34:22.943Z", "enrich_model": "composer-2.5:run-41f40649-c3d1-42d1-aa57-cbca6dc12f22", "enrich_notes": "OC Local Drainage Manual defers WQ BMP sizing to OC DAMP/WQMP TGD (e.g. BIO-2 vegetated swale). LDM Ch.7 covers local flood detention; WQ retention/wet-pond volume is additive per DAMP. Only explicit swale slope cap (6% max bed slope) appears in LDM text; perforated risers noted for extended detention without drain-time hours.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dallas-tx", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dallas-tx/", "data_url": "https://stormwateratlas.com/data/manuals/dallas-tx.json", "document_metadata": { "jurisdiction_name": "Dallas / North Central Texas (iSWM)", "jurisdiction_level": "municipality", "state_code": "TX", "document_title": "iSWM Criteria Manual for Site Development and Construction", "version_or_edition": "Revised January 2015 (December 2009 base)", "adoption_or_effective_date": "2015-01", "last_revised_date": "2015-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 25, 100 ], "water_quality_volume_method": "Water Quality Protection Volume (WQv) based on 1.5 inches of rainfall (85th percentile storm), not a return-period storm. Option 2: treat WQv by reducing TSS from the development site for runoff from rainfalls up to 1.5 inches. Primary structural controls sized for WQv are expected to remove about 70–80% of annual average TSS load when designed per specifications. Methods to compute WQv referenced to Water Quality Technical Manual Section 1.2.", "peak_flow_calculation_method": [ "Rational Method", "SCS Unit Hydrograph Method", "Streambank Protection: control 1-year, 24-hour storm (Streambank Protection Volume / SPV), including 24-hour extended detention option", "Conveyance: 25-year, 24-hour storm", "Flood Mitigation: 100-year, 24-hour storm", "Downstream assessment required for streambank protection, conveyance, and flood mitigation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Enhanced swales (dry, wet, wetland)", "Detention", "Filter strips", "Sand filters / filter boxes", "Infiltration wells and trenches", "Ponds", "Porous surfaces", "Green roofs", "Rainwater harvesting", "Wetlands", "Submerged gravel wetlands", "Alum treatment", "Proprietary systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "assists cities and counties to achieve their goals of water quality protection, streambank protection, and flood mitigation", "page_or_section": "Introduction / Program purpose" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "criteria that cities and counties may use as a component of their stormwater management related development regulations", "page_or_section": "Criteria Manual overview" }, { "field": "document_metadata.state_code", "excerpt": "TPDES Stormwater permit", "page_or_section": "Table 1.3 Water Quality Option 3" }, { "field": "document_metadata.document_title", "excerpt": "iSWM Criteria Manual", "page_or_section": "Running header / title" }, { "field": "document_metadata.version_or_edition", "excerpt": "December 2009 / Revised 1/2015", "page_or_section": "Footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised 1/2015", "page_or_section": "Footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised 1/2015", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The criteria may be customized by local governments to meet specific local needs", "page_or_section": "Criteria Manual introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "\"Streambank Protection\" 1-year, 24-hour storm event; \"Conveyance\" 25-year, 24-hour storm event; \"Flood Mitigation\" 100-year, 24-hour storm event", "page_or_section": "Table 1.2 Storm Events" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "\"Water Quality\" Criteria based on a volume of 1.5 inches of rainfall, not a storm frequency", "page_or_section": "Table 1.2 Storm Events" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Option 2: Treat the Water Quality Protection Volume (WQV) by reducing total suspended solids from the development site for runoff resulting from rainfalls of up to 1.5 inches (85th percentile storm)", "page_or_section": "Table 1.3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "Section 3.2.3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational Method / SCS Unit Hydrograph Method", "page_or_section": "Technical methods list" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Provide on-site controlled release of the 1-year, 24-hour storm event over a period of 24 hours (Streambank Protection Volume, SPV)", "page_or_section": "Table 1.3 Streambank Protection Option 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "secondary controls. • Bioretention • Enhanced swales (dry, wet, wetland) • Alum treatment • Detention • Filter strips • Sand filters, filter boxes, etc • Infiltration wells and trenches • Ponds • Porous surfaces • Proprietary systems • Green roofs • Rainwater harvesting • Wetl", "page_or_section": "p. 29" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality Protection Volume (WQv) is the runoff from the first 1.5 inches of rainfall.", "page_or_section": "page 29 / Section 3.2.3" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treat the Water Quality Protection Volume by reducing total suspended solids from the development site for runoff resulting from rainfall of 1.5 inches (85th percentile storm).", "page_or_section": "page 28 / Section 3.2.3" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration Trenches Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Modular Porous Paver Systems Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 3.20 Soils, page 62" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Wet Pond Limit maximum normal pool depth to about 4 ft (dugout)", "page_or_section": "Table 3.19 Physiographic Factors, pages 60-61" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention Areas Bioretention Areas 80% P S S -", "page_or_section": "Table 3.6, page 30" }, { "field": "practice_mentions.swale", "excerpt": "Enhanced Swales 80% P S S S", "page_or_section": "Table 3.6, page 31" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention, Extended Dry 65% S P P P", "page_or_section": "Table 3.6, page 31" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Third-party sources could include Technology Acceptance Reciprocity Partnership, Technology Assessment Protocol – Ecology, or others.", "page_or_section": "Table 3.2 footnote, page 112 TriSWM Appendix" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "NCTCOG iSWM Criteria Manual is regional guidance adopted/customized by many North Texas cities including Dallas. Local Provision boxes may alter criteria city-by-city; verify City of Dallas local provisions. Detailed hydrologic software requirements live in companion Technical Manuals, not mandated by name in this Criteria Manual.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://iswm.nctcog.org/Documents/iSWM_Criteria_Manual_01142015.pdf", "landing_page_url": "https://iswm.nctcog.org/criteria-manual.html", "retrieved_at": "2026-08-10T07:50:00.000Z", "original_filename": "dallas-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:00:59.178Z", "enrich_model": "composer-2.5:run-f89df759-d147-47b6-a3ef-404e873845b2", "enrich_notes": "WQv is runoff from the first 1.5 inches of rainfall (85th percentile storm); hydrology in Water Quality Technical Manual Section 1.2. Primary structural controls sized for WQv are presumed to remove 70–80% annual average TSS when built per Site Development Controls Technical Manual specs. This Criteria Manual is screening/suitability tables; dimensional BMP criteria are largely in companion technical manuals. Practice-specific depth-to-water-table values appear in tables (often 2 ft for bioretention/detention/sand filters; 1–4 ft for infiltration practices) but no single site-wide SHWT separation is stated. Proprietary systems may cite third-party verification examples including Technology Acceptance Reciprocity Partnership and Technology Assessment Protocol – Ecology.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dekalb-county-ga", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dekalb-county-ga/", "data_url": "https://stormwateratlas.com/data/manuals/dekalb-county-ga.json", "document_metadata": { "jurisdiction_name": "DeKalb County", "jurisdiction_level": "county", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (county adopts GSMM 2016)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "DeKalb County adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "DeKalb County", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treating storm events of 1.2 inches or less", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "SCS Curve Number Method", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "VOL 1 page 120, STANDARD #4 – WATER QUALITY" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "VOL 1 page 120, STANDARD #4 – WATER QUALITY" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "VOL 1 page 120, STANDARD #5 – STREAM CHANNEL PROTECTION" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs", "page_or_section": "VOL 1 page 120, STANDARD #5 – STREAM CHANNEL PROTECTION" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "County coverage via GSMM 2016 as adopted regional/state technical manual. Replace with county-specific supplement PDF if a durable public URL is found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:15:00.000Z", "original_filename": "dekalb-county-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:04:44.725Z", "enrich_model": "composer-2.5:run-219e1ca1-32c2-4fef-a9ac-c4c08679f736", "enrich_notes": "County adopts GSMM 2016; WQv is runoff from 1.2 in rainfall with 80% TSS goal; full 1.0 in runoff reduction (RRV) may waive WQv treatment. Stream channel protection uses 24-hr extended detention of the 1-yr 24-hr storm (CPv). BMP detail dimensions referenced to Volume 2 Chapter 4, not in these Vol 1 excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "de-deldot-drainage", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/de-deldot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/de-deldot-drainage.json", "document_metadata": { "jurisdiction_name": "Delaware", "jurisdiction_level": "state", "state_code": "DE", "document_title": "DelDOT Road Design Manual Ch.6 Drainage and Stormwater Management", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-RAS", "PondPack" ], "approved_bmp_categories": [ "Bioretention", "Filter Strip" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "DelDOT Road Design Manual Ch.6 Drainage and Stormwater Management", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "http://msc.fema.gov), if available, for 100-year flood plain location and elevation; • Existing drainage facilities with design", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ds of hydrological analysis include the Rational Method; TR-20 Project Formulation Hydrology Program System; TR- 55 Urban Hydrol", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "program HEC-RAS is recommended. iii. Filter strips, biofiltration swales, bioretention areas and infiltration ditches are designed using DURMM, DNREC’s green technology computer model based on a combination of computer routines from TR-22 and TR-55. b. Pavement (Storm) Drainag", "page_or_section": "p. 7" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "it allows the pre-development flow to slowly be released over a 24-hr period into the outfall channel while a permanent pool of water is retained in the pond", "page_or_section": "6.11.3.3 OUTLET HYDRAULICS, page 66" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Vs is to be released over a 24-hr period", "page_or_section": "Attachment B Example Problem, page 108" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "assume a trapezoidal shape with a length (in the direction of flow) to width ratio of 2:1 or greater", "page_or_section": "Attachment B Example Problem, page 108" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "desired between length to width of at least 2:1 as selected in the example", "page_or_section": "Attachment B Example Problem, page 109" }, { "field": "practice_mentions.bioretention", "excerpt": "Filter strips, biofiltration swales, bioretention areas and infiltration ditches are designed using DURMM", "page_or_section": "6.4 Step 3 Hydraulics, page 7" }, { "field": "practice_mentions.swale", "excerpt": "a runoff velocity of 1 fps for the design storm", "page_or_section": "6.12.2 BIOFILTRATION, page 68" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet ponds are to have a forebay to act as a sediment trap and two ten foot (10 ft) wide safety benches", "page_or_section": "6.10.5 / checklist, page 63" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. DelDOT Road Design Manual Ch.6 Drainage and Stormwater Management Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://deldot.gov/Publications/manuals/road_design/pdfs/06_drainage_stormwater_mgmt.pdf", "landing_page_url": "https://roaddesignmanual.deldot.gov/index.php/Home", "retrieved_at": "2026-08-11T17:59:10.579Z", "original_filename": "de-deldot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:03:52.395Z", "enrich_model": "composer-2.5:run-0a732b03-3a1e-4a45-bec6-fae4610132cf", "enrich_notes": "Chapter 6 defers detailed green-BMP sizing to DNREC DURMM and Green Technology manual; DelDOT excerpts cite practices qualitatively and wet-extended-detention pond procedure (Figure 6-30) with 24-hr release. Filter strips and biofiltration swales are discussed; numeric WQV depth and bioretention media depths are not in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "de-wet-ponds-draft", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/de-wet-ponds-draft/", "data_url": "https://stormwateratlas.com/data/manuals/de-wet-ponds-draft.json", "document_metadata": { "jurisdiction_name": "Delaware", "jurisdiction_level": "state", "state_code": "DE", "document_title": "BMP Standards and Specifications — 13.0 Wet Ponds", "version_or_edition": "Section 13.0 Wet Ponds (DRAFT strikethrough public-notice revision)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Wet ED Ponds receive RPv credit by providing 48-hour extended detention of the Resource Protection Volume (RPv); Wet Quantity Management Ponds used solely for quantity management receive 0% RPv retention credit. Exact RPv depth/volume definition is deferred to the Delaware Sediment and Stormwater Regulations (not restated in this chapter).", "peak_flow_calculation_method": [ "Site-adjusted runoff curve number (RCN) reflecting upland volume reduction when computing Cv and Fv", "Outflow hydrograph peak discharge not exceeding five times the average discharge rate (for 48-hour RPv extended detention)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Quantity Management Pond (13-A)", "Wet Extended Detention (ED) Pond (13-B)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Wet Ponds constructed to meet regulatory stormwater management requirements in the State of Delaware shall be designed and constructed in accordance with the USDA NRCS Pond Code 378 as amended.", "page_or_section": "Section 13.2 / 13.4" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Wet Ponds constructed to meet regulatory stormwater management requirements in the State of Delaware", "page_or_section": "Section 13.2" }, { "field": "document_metadata.state_code", "excerpt": "design shall be provided to DNREC or their delegated Agency.", "page_or_section": "Section 13.6, Liners" }, { "field": "document_metadata.document_title", "excerpt": "BMP Standards and Specifications Wet Ponds ... 13.0 Wet Ponds", "page_or_section": "Header / Section 13.0" }, { "field": "document_metadata.version_or_edition", "excerpt": "13.0 Wet Ponds", "page_or_section": "Section 13.0; source PDF filename 13-0-Wet-Ponds-DRAFT-strikethrough.pdf" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Additionally, Wet Quantity Management Ponds and Wet ED Ponds should be sized to manage the Conveyance Event and Flooding Event as required in accordance with the Delaware Sediment and Stormwater Regulations.", "page_or_section": "Section 13.6" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The total storage, including any ponding for larger flooding events (100-year storm) should not extend more than 5 feet above the permanent pool unless specific design enhancements to ensure side slope stability, safety, and maintenance are identified and approved.", "page_or_section": "Section 13.6, Maximum Extended Detention Levels" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "A Wet ED Pond differs from a typical Wet Quantity Management Pond in that a Wet ED Pond provides 48-hour detention of all or a portion of the Resource Protection Volume (RPv).", "page_or_section": "Section 13.0" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Wet Quantity Management Ponds used solely for quantity management receive 0% retention credit (RPv) and 0% pollutant removal credit as outlined in Table 13.1a. Wet ED Ponds that provide 48-hour detention receive full credit for the portion of the RPv managed", "page_or_section": "Section 13.1, Tables 13.1a–13.1b" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For RPv compliance, a Wet ED Pond must provide 48 hours extended detention for the RPv runoff volume.", "page_or_section": "Section 13.6 / Table 13.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For treatment train designs where upland practices are utilized for treatment of the resource protection storm (RPv), designers can use a site-adjusted runoff curve number (RCN) that reflects the volume reduction of upland practices to compute the Cv and Fv that will be treated by the Wet Pond.", "page_or_section": "Section 13.6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "In order to simulate a base flow condition to the extent practicable, the peak discharge for the outflow hydrograph shall not exceed five times the average discharge rate.", "page_or_section": "Section 13.6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Design variants include: 13-A Wet Quantity Management Pond; 13-B Wet Extended Detention (ED) Pond", "page_or_section": "Section 13.0" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "a Wet ED Pond must provide 48 hours extended detention for the RPv runoff volume", "page_or_section": "13.6 / page 11" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Wet ED Ponds that provide 48-hour detention receive full credit", "page_or_section": "13.1 / page 3" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum depth = 4'; maximum depth = 8'", "page_or_section": "13.6 Table 13.2 / page 5" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The minimum depth to prevent the permanent pool area from being overtaken by undesirable vegetation is 4 feet", "page_or_section": "13.6 / page 12" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The forebay should have a length to width ratio of 2:1 or greater", "page_or_section": "13.5 / page 10" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The total length of the flow path ... should be a minimum ratio of 2:1", "page_or_section": "13.6 / page 12" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "a diameter capable of draining the Wet Pond within 24 hours", "page_or_section": "13.6 / page 14" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high groundwater table is two feet or more below the proposed Wet Pond invert", "page_or_section": "13.3 / page 8" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "INF = Monthly infiltration loss (assume 7.2 @ 0.01 inch/hour)", "page_or_section": "13.6 Equation 13.1 / page 11" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "DRAFT public-notice chapter (source PDF: 13-0-Wet-Ponds-DRAFT-strikethrough.pdf) — not a final adopted manual by itself. Covers only Wet Ponds post-construction BMP standards. RPv/Cv/Fv event definitions and numeric depths are referenced to the Delaware Sediment and Stormwater Regulations rather than fully specified here; only the 100-year flooding-event storage limit is explicit. No required hydrologic/hydraulic software named. No adoption/effective date in text.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://documents.dnrec.delaware.gov/Admin/Public-Notices/WSS20260001/13-0-Wet-Ponds-DRAFT-strikethrough.pdf", "landing_page_url": "https://dnrec.delaware.gov/watershed-stewardship/sediment-stormwater/", "retrieved_at": "2026-08-08T10:16:22.022Z", "original_filename": "de-wet-ponds-draft.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "wet_pond" ], "enriched_at": "2026-08-13T08:04:21.359Z", "enrich_model": "composer-2.5:run-0f8db6d9-7b4e-4fd9-9710-7bf9318b5cf0", "enrich_notes": "DRAFT DE Chapter 13 wet ponds only; RPv/Cv/Fv numeric depths deferred to Delaware Sediment and Stormwater Regulations. Wet ED Pond requires 48-hr RPv detention. Permanent pool 4–8 ft (48–96 in). Forebay L:W ≥2:1; main pond flow-path L:W ≥2:1. Infiltration >1.0 in/hr at invert with SHWT ≥2 ft below invert triggers alternative BMP. Water balance uses 0.01 in/hr infiltration and 24 in minimum reservoir.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "des-moines-ia", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/des-moines-ia/", "data_url": "https://stormwateratlas.com/data/manuals/des-moines-ia.json", "document_metadata": { "jurisdiction_name": "Des Moines / Iowa SUDAS", "jurisdiction_level": "municipality", "state_code": "IA", "document_title": "SUDAS Design Manual — Chapter 2 Stormwater", "version_or_edition": "Chapter 02 (SUDAS Design Manual)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Defines Water Quality Volume (WQv) and Recharge Volume (Rev). City of Des Moines also adopts Iowa Stormwater Management Manual (ISWMM) for post-construction practices; SUDAS Chapter 2 covers conveyance, detention practices (2G), and minor/major design storm concept.", "peak_flow_calculation_method": [ "Minor design storm (generally 2- to 10-year) for conveyance", "Major design storm (typically 100-year) for flood routing", "Detention basin design methods (Section 2G)", "Master drainage plan flow routing where available" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention practices", "Storm sewer / intake conveyance", "Water quality / recharge volume practices (cross-ref ISWMM)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "SUDAS Design Manual Chapter 2 Stormwater", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Iowa Statewide Urban Design and Specifications", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "--- page 1 --- TOC Design Manual Chapter 2 - Stormwater Table of Contents Table of Contents i Revised: 2021 Edition Chapter 2 - Stormwater 2A General Information 2A-1--------------------------------General Information A. Concept…………………………………………………………………………... 1 B. Informin", "page_or_section": "p. 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Chapter_02.pdf SUDAS Design Manual", "page_or_section": "Source" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "minor (or ordinary) storm recurring at regular intervals, generally 2 to 10 years / major ... 100 year storm event", "page_or_section": "Minor and Major Design Storms" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume, WQv", "page_or_section": "Definitions / criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "2G Detention Practices / Detention Basin Design Methods", "page_or_section": "Chapter 2G" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Practices / stormwater facilities", "page_or_section": "2G" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For Iowa, this equates to providing water quality treatment for the runoff resulting from a rainfall depth of 1.25 inches or less.", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 (page 9)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Provide 24 hours of extended detention of the runoff from the 1 year 24 hour duration storm event to reduce bank-full flows", "page_or_section": "2A-1 D. Unified Sizing Criteria, Table 2A-1.01 Channel Protection Storage Volume, Cpv (page 9)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Channel Protection Storage Volume, Cpv ... Provide 24 hours of extended detention", "page_or_section": "Table 2A-1.01 (page 9)" }, { "field": "practice_mentions.swale", "excerpt": "Open Channel Flow - Swales and Ditches: 1) Describe swale and ditch design.", "page_or_section": "2A-4 Project Drainage Report, 4.d (page 22)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "SUDAS Ch.2 used as Des Moines design reference alongside ISWMM; consider adding ISWMM criteria chapter later. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.iowasudas.org/wp-content/uploads/sites/15/2020/03/Chapter_02.pdf", "landing_page_url": "https://www.dsm.city/Stormwater_Management_Review450.php", "retrieved_at": "2026-08-10T08:41:07.399Z", "original_filename": "des-moines-ia.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T08:06:48.324Z", "enrich_model": "composer-2.5:run-7fb81107-407e-496e-b8b5-2ed957ae7590", "enrich_notes": "SUDAS Ch.2 defines unified sizing (WQv 1.25 in rainfall depth for Iowa, Cpv 24 hr extended detention) but defers post-construction water-quality BMP dimensions to Iowa Stormwater Management Manual (ISWMM). Excerpts cover conveyance, detention release rates, and open-channel/swale reporting requirements—not SCM detail criteria.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dc-ddot-stormwater", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dc-ddot-stormwater/", "data_url": "https://stormwateratlas.com/data/manuals/dc-ddot-stormwater.json", "document_metadata": { "jurisdiction_name": "District of Columbia", "jurisdiction_level": "state", "state_code": "DC", "document_title": "DDOT Green Infrastructure Standards", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Infiltration Basin", "Filter Strip", "Permeable Pavement", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "District of Columbia", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "DDOT Green Infrastructure Standards", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year design storms referenced", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ands viii. Soil boundary lines based on NRCS Hydrologic Soil Group (A, B, C, D, Urban Land) ix. Hot spots (gas stations, con", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Infiltration Basin, Filter Strip, Permeable Pavement", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The reservoir layer is an open graded stone, typically #2, #3, or #57 stone, under the choker layer, for meeting the 1.2 inch retention volume requirement", "page_or_section": "33.14.4.3 Permeable Pavement Base Design" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Tree space with expanded soil volume will serve as a method of capturing and retaining the required 1.2 inches of stormwater in accordance with DDOE requirements", "page_or_section": "47.7.6 Stormwater Retention and Treatment Volume" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of permeable pavement system must be located at least two feet above the seasonally high water table", "page_or_section": "33.14.4.6 Limitations" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of bioretention must be located at least two feet above the seasonally high water table", "page_or_section": "33.14.5.7 Limitations" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The soil profile within Basins, Curb Extensions, Planters and Bioswales shall consist of 18 to 36 inches of Bioretention Soil", "page_or_section": "33.14.5.2 Bioretention Cross Section" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Areas with trees shall contain a minimum of 24\" inches of soil, 30\" preferred", "page_or_section": "33.14.5.2 Bioretention Cross Section" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The maximum allowed ponding depth in bioretention is 18 inches", "page_or_section": "33.14.5.4 Allowable Ponding Depths" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time for 1.2 inches of runoff volume over the contributing drainage area shall be 24 hours minimum and 48 hours maximum", "page_or_section": "33.14.4.4 Stormwater Conveyance and Retention" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Design for drawdown time of 72 hours maximum for the 1.2 inches of runoff volume (to the maximum extent practicable) over the contributing drainage", "page_or_section": "33.14.5.5 Bioretention Sizing and Hydraulic Design" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "with a minimum of 6\" where above tree soil volume, and a minimum of 4\" otherwise", "page_or_section": "33.14.4.3 Pedestrian Use Permeable Pavement Systems" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. DDOT Green Infrastructure Standards (2014)", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://ddot.dc.gov/sites/default/files/dc/sites/ddot/publication/attachments/2014-Final%20DDOT%20Green%20Infrastructure%20Standards.pdf", "landing_page_url": "https://ddot.dc.gov/GreenInfrastructure", "retrieved_at": "2026-08-11T17:59:10.614Z", "original_filename": "dc-ddot-stormwater.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:02:44.892Z", "enrich_model": "composer-2.5:run-23999ba1-0159-41e1-9794-689b4cb12a24", "enrich_notes": "Retention sizing references 1.2 inches of runoff/stormwater per DDOE MEP. Drawdown limits are practice-specific: permeable pavement 24–48 hours for 1.2 inches; bioretention 72 hours maximum for 1.2 inches. Pedestrian permeable aggregate base minimum depths 4 inches (general) or 6 inches (above tree soil / infiltration cases). Bioretention filter soil 18–36 inches (24 minimum with trees). NRCS table gives infiltration thresholds (>0.5, 0.14–0.5, <0.14 in/hr) for underdrain requirements, not a single design infiltration rate.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "dc-guidebook", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/dc-guidebook/", "data_url": "https://stormwateratlas.com/data/manuals/dc-guidebook.json", "document_metadata": { "jurisdiction_name": "District of Columbia", "jurisdiction_level": "municipality", "state_code": "DC", "document_title": "District of Columbia Stormwater Management Guidebook", "version_or_edition": "Appendices A–U, changes accepted July 29, 2013", "adoption_or_effective_date": "2013-07-29", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 15, 100 ], "water_quality_volume_method": "Stormwater Retention Volume (SWRv) is calculated as P/12 × Rv × SA, where P is a percentile rainfall depth that varies by project type (90th percentile, 1.2 inches for major land-disturbing activities; 80th percentile, 0.8 inches for major substantial improvements; 85th percentile, 1.0 inches for major substantial improvements in the Anacostia Waterfront Development Zone). In the AWDZ, Water Quality Treatment Volume (WQTv) uses the 95th percentile depth of 1.7 inches with the same formula.", "peak_flow_calculation_method": [ "Urban Hydrology for Small Watersheds TR-55", "Storage-Indication Routing", "NRCS TR-55 Curve Number Method", "Modified CN Method", "Rational Method" ], "required_hydrologic_hydraulic_software": [ "HEC-1", "WinTR-55", "TR-20", "SWMM" ], "approved_bmp_categories": [ "Green Roofs", "Rainwater Harvesting", "Simple Disconnection", "Permeable Pavement Systems", "Bioretention", "Stormwater Filtering Systems", "Stormwater Infiltration", "Grass Channels", "Dry Swales", "Wet Swales", "Stormwater Ponds", "Stormwater Wetlands", "Storage Practices", "Proprietary Practices", "Tree Planting", "Tree Preservation" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Public right-of-way (PROW) projects within the District of Columbia are owned and operated by", "page_or_section": "Appendix B" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The PROW occupy approximately 25 percent of the impervious area of the District of Columbia", "page_or_section": "Appendix B" }, { "field": "document_metadata.state_code", "excerpt": "Hydrologic Soil Groups approved for use in the District are contained in the Soil Survey of the District of Columbia Handbook.", "page_or_section": "Appendix H, Page H-2" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Guidebook and the District of Columbia Department of", "page_or_section": "Appendix B" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "DDOE's Stormwater Management Guidebook (SWMG)", "page_or_section": "Appendix E" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Detention is required to reduce the peak discharge rate from the 2-year storm event to the preproject peak discharge rate ... discharge rate from the 15-year storm event", "page_or_section": "Appendix A, Design Examples" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For major land-disturbing activities, the SWRv is based upon the 90th percentile depth (1.2 inches). ... SWRv = P/12 × Rv × SA ... the WQTv ... is based upon the 95th percentile depth (1.7 inches).", "page_or_section": "Appendix A, Pages A-1 to A-3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Urban Hydrology for Small Watersheds TR-55 (TR-55) ... Storage-Indication Routing ... HEC-1, WinTR-55, TR-20, and SWMM Computer Models ... Rational Method (limited to sites under five acres)", "page_or_section": "Appendix H, Page H-1" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HEC-1, WinTR-55, TR-20, and SWMM Computer Models", "page_or_section": "Appendix H, Section H.4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Green Roofs ... Rainwater Harvesting ... Permeable Pavement Systems - Enhanced ... Bioretention - Standard ... Stormwater Infiltration ... Stormwater Ponds ... Stormwater Wetlands ... Tree Planting ... Tree Preservation", "page_or_section": "Appendix A, Page A-6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For major land-disturbing activities, the SWRv is based upon the 90th percentile depth (1.2 inches). For major substantial improvements, the SWRv is based upon the 80th percentile depth (0.8 inches).", "page_or_section": "Appendix A, A-1" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "If the seasonally high water table is determined to be less than two feet from the bottom of the proposed BMP, infiltration may not be appropriate.", "page_or_section": "Appendix B, B-9" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The water table must be at least 2 feet below the underdrain, or 5.5 feet below the surface.", "page_or_section": "Appendix A, A-15" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The measured permeability of the underlying soils must be at least 0.5 inches/hour.", "page_or_section": "Appendix A, A-25" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If the results of initial feasibility assessment show that a suitable infiltration rate (typically greater than 0.5 inches per hour) is possible or probable, then test pits must be dug", "page_or_section": "Appendix O, O-2" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "d = media depth (in.) (minimum 3 in.)", "page_or_section": "Appendix A, A-30 (Equation 3.1)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 0.5-foot ponding depth", "page_or_section": "Appendix A, A-13" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a ponding depth of 0.75 feet, a filter media depth of 2 feet", "page_or_section": "Appendix A, A-27" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Extracted from 2013 SWMG appendices A–U; main guidebook chapters were not in this PDF. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://doee.dc.gov/sites/default/files/dc/sites/ddoe/page_content/attachments/FinalGuidebook_changes%20accepted_Appendices%20A-U_07_29_2013_compressed.pdf", "landing_page_url": "https://doee.dc.gov/swguidebook", "retrieved_at": "2026-08-08T01:00:00.000Z", "original_filename": "dc-guidebook.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:03:21.477Z", "enrich_model": "composer-2.5:run-29f5f147-a59e-4e11-940b-ca083963bdb7", "enrich_notes": "DC SWRv regulatory rainfall depths are project-type specific: 1.2 in (90th percentile, major land-disturbing), 0.8 in (80th percentile, major substantial improvement), 1.0 in (85th percentile, AWDZ major substantial improvement); WQTv in AWDZ uses 1.7 in (95th percentile). Bioretention examples use ponding depths of 0.5 ft (6 in), 0.75 ft (9 in), and 1.0 ft (12 in); filter media example depths 1.5–2 ft. Green roof sizing example uses 6 in media depth. SRC ceiling uses P = 1.7 in.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fairfax-county-va", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/fairfax-county-va/", "data_url": "https://stormwateratlas.com/data/manuals/fairfax-county-va.json", "document_metadata": { "jurisdiction_name": "Fairfax County", "jurisdiction_level": "county", "state_code": "VA", "document_title": "Public Facilities Manual (PFM)", "version_or_edition": "2018 PFM (amendments through Oct 20, 2020 in export)", "adoption_or_effective_date": null, "last_revised_date": "2020-10-20", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Chapter 6 Storm Drainage includes Policy on Detention of Stormwaters (6-0300), Stormwater Runoff Quality Control Criteria (6-0400), and Retention/Detention/BMP facilities (6-1300) including bioretention/rain gardens, pervious pavement, and trenches.", "peak_flow_calculation_method": [ "Chapter 6 Storm Drainage — adequate drainage policy", "Detention of stormwaters policy", "Storm sewer / culvert / channel design", "VDOT Drainage Manual references where applicable" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention ponds", "Extended detention", "Retention facilities", "Bioretention / rain gardens", "Pervious pavement", "Low impact development practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "FAIRFAX COUNTY'S PUBLIC FACILITIES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Fairfax County", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "PUBLIC FACILITIES MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "PFM. Similarly, in 1978, the Board adopted a Zoning Ordinance which made specific reference to the requirements in this PFM. 1-0100.2 It is the County’s desire to encourage qualified professionals to seek new and better solutions to complicated technical problems. However, i", "page_or_section": "p. 5" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Fairfax County Public Facilities Manual", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year floodplain limits / 10-Year Tree Canopy", "page_or_section": "Chapter 6 / related" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "6-0400 STORMWATER RUNOFF QUALITY CONTROL CRITERIA", "page_or_section": "Chapter 6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "6-0300 POLICY ON DETENTION OF STORMWATERS", "page_or_section": "Chapter 6" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "bioretention basins or rain gardens / Retention, Detention, and Best Management Practices", "page_or_section": "6-1300" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Facilities must be designed to dewater completely within 48 hours.", "page_or_section": "§ 6-1303 (Infiltration Practices), page 146" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Facilities must be designed to dewater completely within 24 hours.", "page_or_section": "§ 6-1304.2H (Permeable Pavement), page 152" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The treatment volume must drain through the filter section in 24 hours.", "page_or_section": "§ 6-1307.5C (Bioretention), page 165" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The facility must drain completely within 48 hours after the water quality volume has been captured by the filter section.", "page_or_section": "§ 6-1307.6D (Bioretention), page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth between the bottom of the facility and groundwater table or bedrock must be a minimum of 4 feet for infiltration facilities", "page_or_section": "§ 6-1303, page 146" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the facility must be a minimum of 4 feet above the groundwater table and bedrock for facilities designed to provide infiltration and a minimum of 2 feet above the groundwater table and bedrock for all other facilities", "page_or_section": "§ 6-1304.2G (Permeable Pavement), page 152" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth between the bottom of the facility and groundwater table or bedrock must be a minimum of 4 feet for bioretention basins and a minimum of 2 feet for bioretention filters", "page_or_section": "§ 6-1307, page 164" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth between the bottom of the gravel underdrain and the groundwater table or bedrock must be a minimum of 2 feet", "page_or_section": "§ 6-1308.4E (Vegetated Swales), page 175" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "A coefficient of permeability of 1.5 inches/hour for the soil media must be used for sizing calculations.", "page_or_section": "§ 6-1307.5C (Bioretention), page 165" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underdrains must be provided for all infiltration facilities on marginal soils (field measured infiltration rates 0.5 -1.0 in./hr.)", "page_or_section": "§ 6-1303, page 146" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "If large trees and shrubs are to be installed, soil depths must be increased to a minimum of 4 feet.", "page_or_section": "§ 6-1307, page 164" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "hf = maximum ponding depth (ft.)", "page_or_section": "§ 6-1307.5B (Bioretention filter drain time equation), page 165" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Extensive systems are shallow systems, having a growth media depth of 2-6 inches", "page_or_section": "§ 6-1309.1A (Vegetated Roofs), page 179" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Intensive systems have a growth media depth of 6 inches or greater", "page_or_section": "§ 6-1309.1A (Vegetated Roofs), page 179" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "a computation of the ratio of the shortest flow path to overall length of the facility", "page_or_section": "§ 6-1307.12D (Bioretention plan submission), page 171" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "Approvals from the Virginia Department of Environmental Quality (DEQ);", "page_or_section": "§ 6-0402.3B (Manufactured BMPs), page 108" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Large PFM export; Chapter 6 storm drainage confirmed. Pull numeric WQ depth from 6-0400 on review. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition" ] }, "source": { "document_url": "http://online.encodeplus.com/regs/fairfaxcounty-va-pfm/export2doc.aspx?pdf=1&tocid=001", "landing_page_url": "https://www.fairfaxcounty.gov/landdevelopment/public-facilities-manual", "retrieved_at": "2026-08-10T08:34:54.567Z", "original_filename": "fairfax-county-va.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:12:45.985Z", "enrich_model": "composer-2.5:run-01f88a7d-2b56-44cd-9fa5-20fb01540556", "enrich_notes": "Fairfax PFM defers treatment/WQ volume sizing to Virginia Stormwater Design Specifications (P-FIL/BAS); provided excerpts do not state a WQV rainfall depth in inches. Facility dewatering is explicitly 48 hours for infiltration gravel storage, bioretention facilities overall, and bioretention gravel layer after WQ capture; 24 hours for permeable pavement with infiltration and for bioretention filter-section drain (treatment volume through filter). SHWT/bedrock separation is 4 feet (48 in) for infiltration facilities, bioretention basins, and permeable pavement with infiltration; 2 feet (24 in) for bioretention filters, permeable pavement without infiltration focus, and dry swale underdrain bottom. Bioretention sizing uses soil media permeability 1.5 in/hr; marginal infiltration soils cited as 0.5–1.0 in/hr field measured. Bioretention soil depth with large trees/shrubs minimum 4 ft; otherwise per P-FIL-05. Extensive vegetated roofs: growth media 2–6 in; intensive ≥6 in. Manufactured BMPs reference Virginia BMP Clearinghouse and DEQ approvals, not TAPE/NJCAT by name.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fhwa-hds-4", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hds-4/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hds-4.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HDS-4 Introduction to Highway Hydraulics", "version_or_edition": "June 2008", "adoption_or_effective_date": null, "last_revised_date": "2008-06", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "regional regression equations", "statistical analysis of gaged streamflow data", "rainfall intensity-duration-frequency (IDF) analysis", "USGS rural regression equations", "USGS urban regression equations" ], "required_hydrologic_hydraulic_software": [ "National Streamflow Statistics (NSS) program", "HEC-RAS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "In a series of studies by the USGS, in cooperation with the Federal Highway Administration (FHWA) and various other agencies", "page_or_section": "page 39, Section 2.6.2" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "a single seven-parameter regression equation was developed for nationwide application", "page_or_section": "page 39, Section 2.6.3" }, { "field": "document_metadata.document_title", "excerpt": "nomographs for solution of Equation 6.1, for both uniform and for the more complex geometry created by composite cross slopes, are provided in HEC-22 (Brown et al. 2008)", "page_or_section": "page 117, Chapter 6" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "These same procedures are implemented by the FHWA computer program HY-8.", "page_or_section": "page 167, Chapter 9" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Most state highway agencies consider a 10-year frequency storm as the minimum for design of storm drains. Storm drains in sag locations are typically checked for the 50-year frequency storm.", "page_or_section": "page 141, Section 8.2.2 Pipe Sizing" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "When gaged data are not available, estimates are made by empirical equations (e.g., Rational Method) or by regional regression equations.", "page_or_section": "page 27, Section 2.2 STORM RUNOFF" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "When gaged data of adequate length and quality are available, statistical analysis of the flow record can be used to estimate flood peaks for various return periods.", "page_or_section": "page 27, Section 2.2 STORM RUNOFF" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Point rainfall data are used to derive intensity-duration-frequency curves necessary in hydrologic analysis (e.g., as required in the Rational Method; see Section 2.5).", "page_or_section": "page 28, Section 2.4 RAINFALL INTENSITY-DURATION-FREQUENCY ANALYSIS" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The resulting set of equations, referred to as the USGS rural regression equations, were developed primarily for unregulated, natural, nonurbanized watersheds.", "page_or_section": "page 39, Section 2.6.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "To estimate peak discharge in urban areas, equations were developed that modify the rural peak discharge computed as described above.", "page_or_section": "page 39, Section 2.6.3 Urban Regression Equations" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "the USGS compiled all statewide and metropolitan area regression equations into a computer program titled the National Streamflow Statistics (NSS) program.", "page_or_section": "page 39, Section 2.6.4" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Although computer programs (such as HEC-RAS) are commonly used to compute water surface profiles", "page_or_section": "page 101, Section 4.7.3 Standard Step Procedure" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "These same procedures are implemented by the FHWA computer program HY-8.", "page_or_section": "page 167, Chapter 9" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Title/edition corrected from FHWA Highway Drainage publications list (HDS-4, June 2008). Extractor had labeled this HEC-22 because HDS-4 cites that circular. Design storm return periods reflect typical state highway agency practice cited in the manual, not a single FHWA-mandated frequency. No explicit water quality volume method or approved BMP category list in supplied hydrology excerpts.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.relationship_to_state_manual", "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/08090/HDS4_608.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:28:50.930Z", "original_filename": "fhwa-hds-4.pdf" } }, { "slug": "fhwa-hec-14", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hec-14/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hec-14.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HEC-14 Hydraulic Design of Energy Dissipators for Culverts and Channels", "version_or_edition": "3rd edition", "adoption_or_effective_date": null, "last_revised_date": "2006-07", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [ "HEC-RAS", "HY8", "BCAP" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Schall, James D., Everitt V. Richardson, and Johnny L. Morris, 2001. “Introduction to Highway Hydraulics,” Hydraulic Design Series Number 4 (HDS 4), Federal Highway Administration, FHWA-NHI-01-019, August.", "page_or_section": "page 287" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The purpose of this circular is to provide design procedures for energy dissipator designs for highway applications.", "page_or_section": "page 14, CHAPTER 1" }, { "field": "document_metadata.document_title", "excerpt": "The purpose of this circular is to provide design procedures for energy dissipator designs for highway applications.", "page_or_section": "page 14, CHAPTER 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Most of the information presented has been taken from the literature and adapted, where necessary, to fit highway needs.", "page_or_section": "page 14, §1.1" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "HY8 (FHWA culvert analysis software)", "page_or_section": "page 117" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "They should be checked by computing the water surface profile using a standard step method computer program, like HEC-RAS (USACE, 2002).", "page_or_section": "page 51, §4.3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "(This can be calculated using BCAP (Hotchkiss et al. 2004), HY8 (FHWA culvert analysis software), or other calculation tool to determine the depth entering the runout section.)", "page_or_section": "page 117" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Title/edition from FHWA Highway Drainage publications list (HEC-14 3rd ed., July 2006). Corpus covers energy dissipator hydraulics (outlet velocity, scour, dissipator selection), not jurisdiction-wide stormwater design storms or WQ volume methods.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/06086/hec14.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:32:48.891Z", "original_filename": "fhwa-hec-14.pdf" } }, { "slug": "fhwa-hec-15", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hec-15/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hec-15.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HEC-15 Design of Roadside Channels with Flexible Linings", "version_or_edition": "3rd edition", "adoption_or_effective_date": null, "last_revised_date": "2005-09", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Manning's equation combined with the continuity equation for normal flow depth at design discharge" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "vegetation", "rock riprap", "wire-enclosed riprap (gabions)", "turf reinforcement mats", "erosion control blankets", "gravel mulch", "composite linings", "rigid linings (concrete, asphaltic concrete)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "FHWA (1998) provides detailed design guidance for selecting geotextiles as a riprap filter material.", "page_or_section": "6.4.3 Riprap Filter Design, page 109" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "FHWA (1998) provides detailed design guidance for selecting geotextiles as a riprap filter material.", "page_or_section": "6.4.3 Riprap Filter Design, page 109" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "The manual was dated October 1975.", "page_or_section": "document scope (not in excerpt body)" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The design method presented in this circular is based on the concept of maximum permissible tractive force.", "page_or_section": "Chapter 2: Design Concepts, page 27" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "FHWA (1998) provides detailed design guidance for selecting geotextiles as a riprap filter material.", "page_or_section": "6.4.3 Riprap Filter Design, page 109" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Design flow rates for permanent roadside and median drainage channel linings usually have a 5 or 10-year return period. A lower return period flow is allowable if a transitional lining is to be used, typically the mean annual storm (approximately a 2-year return period, i.e., 50 percent probability of occurrence in a year).", "page_or_section": "2.3.1 Design Discharge Frequency, pages 33-33" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The condition of uniform flow in a channel at a known discharge is computed using the Manning's equation combined with the continuity equation:", "page_or_section": "2.1.2 Normal Flow Depth, page 27" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Design Discharge: Discharge at a specific location defined by an appropriate return period to be used for design purposes.", "page_or_section": "Glossary, page 10" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Vegetative linings consist of seeded or sodded grasses placed in and along the channel", "page_or_section": "1.4.1.1 Vegetation, page 17" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Rock riprap is placed on a filter blanket or prepared slope to form a well-graded mass with a minimum of voids", "page_or_section": "1.4.1.3 Rock Riprap, page 19" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wire-enclosed riprap (gabions) is a wire container or enclosure structure that binds units of the riprap lining together.", "page_or_section": "1.4.1.4 Wire-Enclosed Riprap, pages 20-21" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "A TRM is a non-degradable RECP composed of UV stabilized synthetic fibers, filaments, netting and/or wire mesh processed into a three-dimensional matrix.", "page_or_section": "1.4.1 Turf Reinforcement, pages 20-21" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Erosion Control Blanket (ECB): A degradable material, composed primarily of processed natural organic materials, manufactured or fabricated into rolls designed to reduce soil erosion", "page_or_section": "Glossary, page 10" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Title/edition from FHWA Highway Drainage publications list (HEC-15 3rd ed., September 2005). Extractor had used the 1975 first-edition date. Manual focuses on channel lining shear stress design, not water-quality volume or specified hydrologic software.", "fields_not_found": [ "document_metadata.document_title", "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/05114/05114.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:30:40.301Z", "original_filename": "fhwa-hec-15.pdf" } }, { "slug": "fhwa-hec-21", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hec-21/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hec-21.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HEC-21 Design of Bridge Deck Drainage", "version_or_edition": "May 1993", "adoption_or_effective_date": null, "last_revised_date": "1993-05", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 50 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [ "HYDRAIN", "HYDRO" ], "approved_bmp_categories": [ "retention ponds", "detention ponds" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Data from the NWS have been incorporated into the HYDRO computer program of the HYDRAIN (Young and Krolak, 1992) software package supported by the Federal Highway Administration (FHWA).", "page_or_section": "107" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "software package supported by the Federal Highway Administration (FHWA).", "page_or_section": "107" }, { "field": "document_metadata.document_title", "excerpt": "List of Tables for HEC 21-Design of Bridge Deck Drainage", "page_or_section": "126" }, { "field": "document_metadata.version_or_edition", "excerpt": "Chapter 9 : HEC 21 Bridge Deck Drainage Method", "page_or_section": "49" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual takes the viewpoint that inlets are designed not to clog.", "page_or_section": "106" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "Federal Highway Administration, Hydraulic Design of Energy Dissipators for Culverts and Channels, HEC-14, Washington, D.C., 1983.", "page_or_section": "136" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Functional Class of Roadway ... Frequency (Return Period--years) Interstate ... 10 ... Major Collectors and Arterials ... 10 ... Minor Collectors and Arterials ... 5 ... Local Streets ... 2 ... Depressed Interstate Drained by Pumping Stations ... 50", "page_or_section": "105-106" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Rational Method is presented as the conventional method for determining peak runoff rate for bridge decks.", "page_or_section": "105" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For all cases, the Rational Method design approach is used.", "page_or_section": "49" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The IDF curve can be obtained from HYDRO in the HYDRAIN software using the latitude and longitude coordinates of the site.", "page_or_section": "92" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Data from the NWS have been incorporated into the HYDRO computer program of the HYDRAIN (Young and Krolak, 1992) software package supported by the Federal Highway Administration (FHWA).", "page_or_section": "107" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention and detention ponds, with or without permanent pools, can be provided to attenuate peak flows or provide quiescent conditions to settle out particulates.", "page_or_section": "104" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Title/edition from FHWA Highway Drainage publications list (HEC-21, May 1993). Corpus focuses on bridge deck drainage, not site-scale stormwater BMP design. water_quality_volume_method not addressed in provided text.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/hec/hec21.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:31:48.895Z", "original_filename": "fhwa-hec-21.pdf" } }, { "slug": "fhwa-hec-22", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hec-22/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hec-22.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HEC-22 Urban Drainage Design Manual", "version_or_edition": "4th edition", "adoption_or_effective_date": null, "last_revised_date": "2024-02", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "First-flush / water quality volume (WQV) commonly estimated as: the first 0.5 inch of runoff from impervious area; the first 0.5 inch of runoff from the entire catchment; or the first 1.0 inch of rainfall resulting in runoff from the entire catchment; also V_WQv = Q A = (R_V P) A", "peak_flow_calculation_method": [ "Rational Method", "Statistical analysis (log-Pearson type III)", "NRCS (SCS) peak flow method", "USGS rural regression equations", "USGS nationwide urban regression equations (three-parameter or seven-parameter)", "Unit hydrograph methods" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "SWMM", "WinTR-20", "WinTR-55", "NSS" ], "approved_bmp_categories": [ "detention basins", "retention basins", "water quality control facilities", "best management practices (BMPs)", "infiltration trenches", "infiltration basins", "stormwater quantity and quality control facilities (detention or retention ponds)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "This chapter condenses information from Highway Hydrology, Hydraulic Design Series 2 (HDS-2) (FHWA 2002).", "page_or_section": "Chapter 4, page 53" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Federal, State, and local regulations often guide the quality and quantity of the discharge.", "page_or_section": "Section 3.1, page 47" }, { "field": "document_metadata.document_title", "excerpt": "Table of Contents HEC-22, 4th edition", "page_or_section": "page 10" }, { "field": "document_metadata.version_or_edition", "excerpt": "HEC-22, 4th edition Chapter 3 - System Planning", "page_or_section": "page 47" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "Consult HDS-2 (FHWA 2002) for additional information on these methods.", "page_or_section": "Section 4.2.1, page 55" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The minor system is typically designed to carry runoff from an intermediate design storm event such as the 0.1 annual exceedance probability (AEP) (10-year return period) event.", "page_or_section": "Section 3.2, page 47" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The major system usually carries stormwater during larger, more infrequent storm events, such as the 0.04, 0.02, and 0.01 AEP storms.", "page_or_section": "Section 3.2, page 47" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "A common criterion would be to regulate the 0.5, 0.1, and 0.01 AEP events.", "page_or_section": "Section 10.1.1 Design Events, page 180" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "engineers estimate first flush volume as: • The first 0.5 inch of runoff of impervious area. • The first 0.5 inch of runoff of the entire catchment area. • The first 1.0 inch of rainfall resulting in runoff from the entire catchment area.", "page_or_section": "Section 11.1, page 231" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Engineers estimate the water quality volume using: V WQ Q A (R P)A= = (11.2)", "page_or_section": "Section 11.3.2.1, page 268" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "One of the most used approaches for the calculation of peak flow from small areas is the Rational Method", "page_or_section": "Section 4.2.2, page 55" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The log-Pearson type III distribution is a three-parameter gamma distribution with a logarithmic transform of the independent variable. Designers use it widely for flood analyses", "page_or_section": "Section 4.2.1 Statistical Analysis, page 55" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The NRCS (SCS) peak flow method is another approach that calculates peak flow as a function of drainage basin area, potential watershed storage, and the time of concentration.", "page_or_section": "Section 4.2 Peak Flow, page 55" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Designers can adapt a rural peak flow for urban conditions with the three-parameter or seven-parameter nationwide urban regression equations developed by USGS. NSS can calculate peak flows with both versions.", "page_or_section": "Section 4.2.3.2 Urban Equations, page 64" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "4.3.1 Unit Hydrograph Methods A unit hydrograph is the direct runoff hydrograph resulting from a unit volume of excess rainfall.", "page_or_section": "Section 4.3.1, page 64" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Application of hydrograph methods often necessitates computer programs such as the Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS), the Stormwater Management Model (SWMM), WinTR-20, WinTR-55, among others", "page_or_section": "Section 4.3 Design Hydrographs, page 64" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "NSS can calculate peak flows with both versions.", "page_or_section": "Section 4.2.3.2 Urban Equations, page 64" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "storm drainage systems often rely on detention or retention basins and other best management practices (BMPs) for the control of discharge quantity and quality.", "page_or_section": "Section 3.1, page 47" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "These components include curbs, gutters, ditches, inlets, access holes, pipes and other conduits, open channels, pumps, detention basins, water quality control facilities, etc.", "page_or_section": "Section 3.2, page 47" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater quantity and quality control facilities are either detention or retention ponds.", "page_or_section": "Chapter 10, page 180" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "There are three basic trench systems: complete exfiltration, partial exfiltration, and water quality exfiltration.", "page_or_section": "Section 11.3.2.1, page 268" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "An infiltration basin impounds stormwater flow and gradually exfiltrates it through the floor of an excavated area.", "page_or_section": "Section 11.3.2.2 Infiltration Basins, page 269" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Excerpts are overview/reference material; design storm return periods include multiple contexts (minor/major systems vs. detention regulatory examples). Document full title, adoption dates, and relationship to state manuals not stated in provided chunks. HEC-22 does not mandate a single required software list—programs are cited as commonly used, not exclusively required.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/hif24006.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:27:59.389Z", "original_filename": "fhwa-hec-22.pdf" } }, { "slug": "fhwa-hec-24", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fhwa-hec-24/", "data_url": "https://stormwateratlas.com/data/manuals/fhwa-hec-24.json", "document_metadata": { "jurisdiction_name": "Federal Highway Administration", "jurisdiction_level": "federal", "state_code": null, "document_title": "HEC-24 Highway Stormwater Pump Station Design", "version_or_edition": "February 2001", "adoption_or_effective_date": null, "last_revised_date": "2001-02", "relationship_to_state_manual": "independent", "issuing_agency_category": "other" }, "design_criteria": { "design_storm_return_periods_years": [ 50, 100, 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS Tabular Hydrograph Method (Technical Release 55, TR55)", "NRCS dimensionless unit hydrograph method (Technical Release 20, TR 20)", "Methods available in the computer programs HEC-1 and HEC-HMS" ], "required_hydrologic_hydraulic_software": [ "HEC-1", "HEC-HMS", "HY-22" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Refer to the FHWA publication “Highway Hydrology”, HDS 2,5 for detailed considerations and procedures", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4 Design Hydrograph, pages 65-66" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "mandatory for interstate highways", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.3.2 Design Frequency, pages 65-66" }, { "field": "document_metadata.document_title", "excerpt": "Figure 4-1. Highway Stormwater Pump Station Hydraulic Design Process", "page_or_section": "Chapter 4 – Pump Station Design Process, pages 45-46" }, { "field": "document_metadata.version_or_edition", "excerpt": "queue id fhwa-hec-24; Hydraulic Engineering Circular stormwater pump station manual context", "page_or_section": "Corpus fhwa-hec-24" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The choice of hydrologic methods is either based on agency standard practice or left up to the designer based on local conditions and judgment.", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4.1 Hydrologic Methods, page 66" }, { "field": "document_metadata.issuing_agency_category", "excerpt": "State of the practice hydrologic methods are employed such as appear in the FHWA publication Highway Hydrology.", "page_or_section": "Chapter 4 – Pump Station Design Process, 4.7.1.3 Stage 2, page 52" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The recommended design for a highway stormwater pump station is a return period of 50 years", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.3.2 Design Frequency, pages 65-66" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The standard check flood is one having a return period of 100 years.", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.3.3 Check Frequency, pages 65-66" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "it is recommended that a frequent event, such as a 2-year, be used to check low flow operation", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.3.3 Check Frequency, pages 65-66" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "National Resources Conservation Service (NRCS) – formerly Soil Conservation Service) – Tabular Hydrograph Method of Technical Release 55, Urban Hydrology for Small Watersheds (TR55),8", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4.1 Hydrologic Methods, page 66" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "NRCS dimensionless unit hydrograph method based on Technical Release 20, Hydrology, (TR 20),9", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4.1 Hydrologic Methods, page 66" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Methods available in the computer programs HEC-1 and HEC-HMS.", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4.1 Hydrologic Methods, page 66" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Methods available in the computer programs HEC-1 and HEC-HMS.", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4.1 Hydrologic Methods, page 66" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The FHWA software program HY-2216can be used in conjunction with HEC-2210 to compute storage volumes.", "page_or_section": "Chapter 6 – Storage System, 6.8 Storage Calculations, page 78" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Refer to the FHWA publication “Highway Hydrology”, HDS 2,5 for detailed considerations and procedures for determining runoff hydrographs.", "page_or_section": "Chapter 5 – Site Planning and Hydrology, 5.4 Design Hydrograph, pages 65-66" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Title/edition from FHWA Highway Drainage publications list (HEC-24, February 2001). HY-22 citation appears with OCR artifact. BMPs referenced generically for NPDES compliance but no approved BMP category list. water_quality_volume_method not stated (pump-station hydrology focus).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.fhwa.dot.gov/engineering/hydraulics/pubs/hec/hec24.pdf", "landing_page_url": "https://www.fhwa.dot.gov/engineering/hydraulics/highwaydrain/drainage.cfm", "retrieved_at": "2026-08-14T15:31:17.551Z", "original_filename": "fhwa-hec-24.pdf" } }, { "slug": "fl-fsesci-tier1", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-fsesci-tier1/", "data_url": "https://stormwateratlas.com/data/manuals/fl-fsesci-tier1.json", "document_metadata": { "jurisdiction_name": "Florida", "jurisdiction_level": "state", "state_code": "FL", "document_title": "Florida Stormwater Erosion and Sedimentation Control Inspectors Manual", "version_or_edition": "July 2018", "adoption_or_effective_date": "2018-07", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10 ], "water_quality_volume_method": "Temporary (or permanent) sediment or wet detention basin providing 3,600 cubic feet of storage per acre drained", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Temporary BMPs for Erosion and Sedimentation Control", "BMPs—Vegetation for Erosion Control", "BMPs for Dewatering" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Florida Department of Environmental Protection", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Florida Department of Environmental Protection", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Florida Stormwater Erosion and Sedimentation Control Inspectors Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Florida Department of Environmental Protection", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "peak runoff expected from the drainage area for a 10-year storm", "page_or_section": "Chapter 3, Page 106" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "temporary (or permanent) sediment or wet detention basin providing 3,600 cubic feet of storage per acre drained must be provided", "page_or_section": "Chapter 3, Page 103" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 3: Temporary BMPs for Erosion and Sedimentation Control ... Chapter 4: BMPs—Vegetation for Erosion Control ... Chapter 5: BMPs for Dewatering", "page_or_section": "Contents" }, { "field": "fields_not_found", "excerpt": "0.5-inch or greater storm event. The Construction Generic Permit (CGP) defines a storm event as", "page_or_section": "p18" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The simplest approach to sizing the treatment cell is to multiply the allowable discharge flow rate by the desired drawdown time. A 4-hour drawdown time allows 1 batch per cell per 8-hour work period, given 1 hour of flocculation followed by 2 hours of settling.", "page_or_section": "Chapter 5: BMPs for Dewatering, page 200" }, { "field": "practice_mentions.swale", "excerpt": "A small, temporary dam constructed across a swale or stormwater conveyance channel.", "page_or_section": "Section 3.8 Temporary Check Dam, page 117" }, { "field": "practice_mentions.wet_pond", "excerpt": "Runoff calculations for a 10-year frequency storm.", "page_or_section": "Sediment basin submission requirements, page 116" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.mywaltonfl.gov/DocumentCenter/View/32627/FSESCI-TIER-I-Manual-062918", "landing_page_url": "https://floridadep.gov/dear/florida-stormwater-erosion", "retrieved_at": "2026-08-07T11:34:24.793Z", "original_filename": "fl-fsesci-tier1.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 4, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:15:05.258Z", "enrich_model": "composer-2.5:run-5035799b-cc45-433a-8ce4-48726d516669", "enrich_notes": "Corpus is from the Florida Stormwater Erosion and Sedimentation Control Inspectors Manual (temporary erosion/sediment and construction dewatering BMPs). It does not define post-construction WQv rainfall depth in inches; atlas WQv (3,600 cf/ac) is not stated in these excerpts. USDA Table 2.2 lists soil permeability class ranges (in/hr) for planning only, not a single SCM design infiltration rate. Sediment basin review requires 10-year storm runoff calculations; turbidity discharge limit 29 NTU over background (Ch. 5).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fl-fdot-drainage", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-fdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/fl-fdot-drainage.json", "document_metadata": { "jurisdiction_name": "Florida Department of Transportation (FDOT)", "jurisdiction_level": "state", "state_code": "FL", "document_title": "FDOT Drainage Manual", "version_or_edition": "January 2025", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Florida Department of Transportation (FDOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "FDOT Drainage Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "dian, and Interceptor Ditches or Swales 10-year Outfalls 25-year Canals 25-year Temporary Roadside and Median Ditches or Swales", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "sion Equations developed by the USGS b. Rational Equation for drainage areas up to 600 acres c. For outfalls from stormwater man", "page_or_section": null }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The minimum ditch bottom elevation is one foot above the estimated seasonal high groundwater elevation for maintainability.", "page_or_section": "Section 2.4.4 Channel Bottom, page 2-4" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "With facilities designed to be wet, provide a minimum permanent pool depth of six feet to minimize aquatic growth.", "page_or_section": "Section 5.4.4.2 item 4, page 5-12" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "The minimum channel bottom width is five feet to accommodate mitered end sections", "page_or_section": "Section 2.4.4 Channel Bottom, page 2-3" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Provide a minimum physical slope of 0.0005 feet/feet for all conveyance ditches.", "page_or_section": "Section 2.4.2 Slope, page 2-2" }, { "field": "practice_mentions.swale", "excerpt": "Roadside, Median, and Interceptor Ditches or Swales", "page_or_section": "Table 2.1, page 2-1" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention Systems (landscaped areas or planters, rain gardens, stormwater trees)", "page_or_section": "Table 5-1, page 5-7" }, { "field": "practice_mentions.wet_pond", "excerpt": "Retention Pond ... Littoral Zone (Wet detention ponds)", "page_or_section": "Table 5-1, page 5-7" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. FDOT Drainage Manual January 2025", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://fdotwww.blob.core.windows.net/sitefinity/docs/default-source/roadway/drainage/files/drainagemanual2025.pdf", "landing_page_url": "https://www.fdot.gov/roadway/drainage/drainage-history", "retrieved_at": "2026-08-11T17:21:05.990Z", "original_filename": "fl-fdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 72, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 60, "swale_longitudinal_slope_percent": 0.05, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_trench", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:14:23.452Z", "enrich_model": "composer-2.5:run-c0531fe7-6bcf-427a-acbe-abe56d75ac8b", "enrich_notes": "FDOT January 2025 Drainage Manual excerpts emphasize roadway drainage, open channels, storm sewers, and Chapter 5 BMP tables. Closed-basin retention must recover so half the volume is available in seven days and the full volume in 30 days (Section 5.4.1.2.2); not mapped to max_drawdown_hours without an explicit hour value. Wet pond fencing variances reference permanent design water depth of two feet or greater. French drain/exfiltration guidance requires invert above water table and prohibits use in well-field zones with less than 30 days travel time; no design infiltration rate or trench storage depth stated. Regulatory design references Chapter 14-86 F.A.C. and NRCS/unit hydrograph methods; no WQv rainfall depth in provided text.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fresno-ca", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fresno-ca/", "data_url": "https://stormwateratlas.com/data/manuals/fresno-ca.json", "document_metadata": { "jurisdiction_name": "Fresno Metropolitan Flood Control District", "jurisdiction_level": "special_district", "state_code": "CA", "document_title": "Post-Development Standards Technical Manual", "version_or_edition": "June 2014", "adoption_or_effective_date": "2014-06", "last_revised_date": "2014-06", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Priority Projects must mitigate SWQDV or SWQDF via LID- or treatment-based BMPs. SWQDV: infiltrate or treat runoff from the 24-hour 85th percentile storm (local rainfall record), or WEF/ASCE maximized capture volume, or volume of annual runoff achieving equivalent treatment to the 85th percentile 24-hour event. County of Fresno drainage standards (pre- vs post-development 100-year runoff volume difference) are noted as more stringent than the 2013 MS4 Permit for areas not covered by the FMFCD Master Plan. Projects discharging to the Regional Stormwater Management Basin System meet LID/treatment requirements via the regional system.", "peak_flow_calculation_method": [ "SWQDF for flow-based BMPs (vegetated filter strips, vegetated swales, some proprietary devices)", "Effective stormwater runoff coefficient from Tables 5-2 (Fresno) and 5-3 (Clovis)", "County of Fresno drainage design: mitigate difference in pre- vs post-development 100-year runoff volume where Master Plan basins do not apply" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention (LID-1)", "Infiltration basin (LID-2)", "Infiltration trench (LID-3)", "Dry well (LID-4)", "Permeable pavement without underdrain (LID-5)", "Rain barrel/cistern (LID-6)", "Green roof (LID-7)", "Biofiltration (T-1)", "Stormwater planter (T-2)", "Tree-well filter (T-3)", "Vegetated filter strips (T-4)", "Vegetated swales (T-5)", "Sand filters (T-6)", "Constructed wetlands (T-7)", "Extended detention basin (T-8)", "Wet pond (T-9)", "Permeable pavement with underdrain (T-10)", "Proprietary devices (T-11)", "Source control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Fresno Metropolitan Flood Control District i June 2014", "page_or_section": "Title / footer" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Fresno Metropolitan Flood Control District", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "2013 MS4 Permit", "page_or_section": "Section 1.1" }, { "field": "document_metadata.document_title", "excerpt": "Post-Development Standards Technical Manual", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "FMFCD has prepared the 2014 Post-Development Standards Technical Manual", "page_or_section": "Section 1.1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "comply with the requirements of the 2013 MS4 Permit", "page_or_section": "Section 1.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "difference in stormwater runoff volume between the pre- and post-development 100-", "page_or_section": "Section 5.3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The volume of stormwater runoff produced from a 24-hour, 85th percentile storm event, as determined from the local historical rainfall record", "page_or_section": "Section 5.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Vegetated Filter Strips (T-4) SWQDF / Vegetated Swales (T-5) SWQDF", "page_or_section": "Table 5-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention (LID-1) SWQDV / Infiltration Basin (LID-2) SWQDV", "page_or_section": "Table 5-1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Bioretention areas are sized such that the SWQDV must be completely infiltrated within 96 hours.", "page_or_section": "LID-1 Bioretention Sizing, C-5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "t = Maximum drawdown time (max 96 hrs) [hr];", "page_or_section": "LID-1 Bioretention Sizing, C-6" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The depth to groundwater beneath the project site during the wet season may preclude infiltration if less than 10 feet of separation exists between the infiltration surface and the seasonal high groundwater or mounded groundwater levels.", "page_or_section": "Section 3 Considerations Groundwater, page 27" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The planting soil depth must be a minimum of two feet, but three feet is preferred.", "page_or_section": "LID-1 Bioretention Geometry, C-4" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Bioretention areas must be sized to capture and retain the SWQDV with an 18- inch maximum ponding depth.", "page_or_section": "LID-1 Bioretention Geometry, C-4" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "d = Ponding depth (max 1.5 ft) [ft];", "page_or_section": "LID-1 Bioretention Sizing, C-5" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "For extended detention wet ponds, the outlet structure should be designed to provide a 96-hour drawdown time for the SWQDV above the permanent pool.", "page_or_section": "T-9 Wet Pond Outlet Structure, C-174" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "The minimum width of the vegetated swale bottom is two feet to allow for ease of mowing.", "page_or_section": "T-4 Vegetated Swales Geometry, C-102" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "FMFCD June 2014 Post-Development Standards Technical Manual (URL updated to 2022/09 hosting path). Covers Fresno-Clovis priority projects outside regional basin service areas; regional basin discharges credited as meeting LID/treatment. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.fresnofloodcontrol.org/wp-content/uploads/2022/09/Post-Development-Standards-Technical-Manual.pdf", "landing_page_url": "https://www.fresnofloodcontrol.org/documents-and-reports/", "retrieved_at": "2026-08-10T07:50:51.242Z", "original_filename": "fresno-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 96, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:22:54.018Z", "enrich_model": "composer-2.5:run-fcd4c405-3f27-428b-843b-e49559289838", "enrich_notes": "SWQDV sizing is volume-based (85th percentile 24-hour storm per atlas/Section 5); no fixed WQv depth in inches in excerpts. Site feasibility uses minimum corrected in-situ infiltration ≥0.5 in/hr; design f_design is calculated from field tests (F_testing 0.25 bioretention, 0.5 basin/trench/dry well). Groundwater: infiltration precluded if <10 ft separation from infiltration surface to seasonal high GW. ED basin bottom ≥2 ft above seasonal high GW. Permeable pavement without underdrain requires ≥3 ft undisturbed medium below base rock to impervious layer. Swale longitudinal slope 1–6% (range, no single design percent). Proprietary devices (T-11) require FMFCD approval; no TAPE/NJCAT named.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fulton-county-ga", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fulton-county-ga/", "data_url": "https://stormwateratlas.com/data/manuals/fulton-county-ga.json", "document_metadata": { "jurisdiction_name": "Fulton County", "jurisdiction_level": "county", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (county adopts GSMM 2016)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Fulton County adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Fulton County", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treating storm events of 1.2 inches or less", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "SCS Curve Number Method", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "VOL 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "VOL 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "VOL 1, Standard #5 – Stream Channel Protection, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The first method of providing stream bank protection is the extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs.", "page_or_section": "VOL 1, Standard #5 – Stream Channel Protection, page 120" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "County coverage via GSMM 2016 as adopted regional/state technical manual. Replace with county-specific supplement PDF if a durable public URL is found. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:15:00.000Z", "original_filename": "fulton-county-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:24:29.023Z", "enrich_model": "composer-2.5:run-666e6f24-3995-4ce7-aea0-ef77fe89736c", "enrich_notes": "WQv is defined as runoff from 1.2 inches of rainfall (85% of average-year storms); RRV is 1.0 inch runoff reduction per Standard #3. Stream channel protection uses 24-hour extended detention of the 1-year, 24-hour storm (CPv). Bioretention cul-de-sac islands require underdrain and/or overflow (Vol. 2 §4.2 cited, not in excerpt). Permanent stormwater infiltration basins prohibited in high pollution susceptibility groundwater recharge areas.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ga-gdot-drainage", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/ga-gdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ga-gdot-drainage.json", "document_metadata": { "jurisdiction_name": "Georgia", "jurisdiction_level": "state", "state_code": "GA", "document_title": "GDOT Drainage Design Policy Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "GDOT Drainage Design Policy Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "latory standard also referred to as the 100-year flood. Bent – A substructure unit supporting the superstructure. It is usually", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Curve Numbers 1.0 11/25/24 Appendix C. Rational Method Runoff Coefficients 1.0 11/25/24 Drainage Design Policy Manual Rev 1.1 L", "page_or_section": null }, { "field": "practice_mentions.swale", "excerpt": "Swale – A broad channel for the conveyance and temporary storage of runoff.", "page_or_section": "Acronyms and Definitions, page xxxviii" }, { "field": "practice_mentions.swale", "excerpt": "Concentrated flow includes flows in gutters, pipes, swales, channels, and streams.", "page_or_section": "Chapter 3. Hydrology, page 3-3" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Drainage Pavement Course – A type of pavement surface such as Open Graded Friction Course, (OGFC), which has specialized characteristics such as higher permeability and friction.", "page_or_section": "Acronyms and Definitions, page xxxi" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Table 3.1 lists Water Quality under Rational Method applications; no water-quality rainfall/runoff depth in inches is stated.", "page_or_section": "Chapter 3. Hydrology, page 3-5" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. GDOT Drainage Design Policy Manual Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.dot.ga.gov/PartnerSmart/DesignManuals/Drainage/Drainage%20Design%20Policy%20Manual.pdf", "landing_page_url": "http://www.dot.ga.gov/GDOT/Pages/designmanualssoftware.aspx", "retrieved_at": "2026-08-11T17:59:10.570Z", "original_filename": "ga-gdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:24:55.298Z", "enrich_model": "composer-2.5:run-f3a19b11-cd57-4523-968a-d541b7d0b889", "enrich_notes": "Excerpts are GDOT highway drainage policy (hydrology, pipes, channels, bridges), not GSMM BMP sizing. Table 3.1 lists Water Quality as a Rational Method application without a WQv depth. GSMM is referenced as additional criteria online. OGFC is noted for permeability; Tc minimum is 5 minutes (not a drawdown field).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ga-state", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/ga-state/", "data_url": "https://stormwateratlas.com/data/manuals/ga-state.json", "document_metadata": { "jurisdiction_name": "Georgia", "jurisdiction_level": "state", "state_code": "GA", "document_title": "Stormwater Management Manual Georgia", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Georgia Stormwater Management Manual is organized as a three volume set", "page_or_section": "1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals... 2-year through the 25-year return frequency storm events", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater management systems shall be designed to retain or treat the runoff from 85% of the storms that occur in an average year, and reduce average annual post-development total suspended solids loadings by 80%. Averaged from rainfall events across the state of Georgia, this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events.", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "What is the SCS curve number for this sub-watershed", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters; Regenerative Stormwater Conveyance; Sand Filters; and Stormwater Planters/Tree Boxes", "page_or_section": "199" }, { "field": "fields_not_found", "excerpt": "tion is the extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs.", "page_or_section": "p120" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "VOL 1 page 120, STANDARD #4 – WATER QUALITY" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "VOL 1 page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "VOL 1 page 120, STANDARD #5 – STREAM CHANNEL PROTECTION" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The first method of providing stream bank protection is the extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs.", "page_or_section": "VOL 1 page 120" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-07T11:19:40.289Z", "original_filename": "ga-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:25:15.907Z", "enrich_model": "composer-2.5:run-9e7cee04-0e41-47e9-853f-32036c0b5cfd", "enrich_notes": "Volume 1 standards: runoff reduction targets first 1.0 inch on site; WQv equals runoff from 1.2 inches when full 1.0 inch RRV is not achieved. Channel protection uses 24-hour extended detention of 1-year 24-hour storm. Coastal flat terrain notes high water table within a few feet of surface but no numeric SHWT setback in these excerpts. BMP detail dimensions referenced to Volume 2 Section 4.2 (bioretention).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "gwinnett-county-ga", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/gwinnett-county-ga/", "data_url": "https://stormwateratlas.com/data/manuals/gwinnett-county-ga.json", "document_metadata": { "jurisdiction_name": "Gwinnett County", "jurisdiction_level": "county", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (GCSMM technical basis / GSMM 2016)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Gwinnett County Stormwater Management Manual based on GSMM", "page_or_section": "County develop resources / GSMM" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Gwinnett County", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals... 2-year through the 25-year return frequency storm events", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "SCS Curve Number Method", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "Vol 1, Standard #4 – Water Quality (page 120)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "If the entire 1.0-inch runoff reduction standard cannot be achieved, the remaining runoff from the 1.2-inch rainfall event must be treated by BMPs", "page_or_section": "Vol 1, Standard #3 – Runoff Reduction (page 119)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection (page 120-121)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs", "page_or_section": "Vol 1, Standard #5 – Stream Channel Protection (page 120-121)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Official GCSMM PDF is portal/HTML-gated. Criteria taken from GSMM 2016 (same technical basis Gwinnett publishes). Prefer swapping source to direct GCSMM PDF if a durable public URL appears. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://www.gwinnettcounty.com/government/departments/water/develop-resources", "retrieved_at": "2026-08-10T09:15:00.000Z", "original_filename": "gwinnett-county-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:29:50.756Z", "enrich_model": "composer-2.5:run-51ec661a-f66d-4abf-84ca-5f08e34de872", "enrich_notes": "Corpus is GSMM Vol. 1 (policy/BSD); WQv 1.2 in and RRV 1.0 in are explicit in Standards #3–#4. Channel protection uses 24-hour extended detention of the 1-year, 24-hour storm (Standard #5). BMP geometry, media depths, SHWT separation, and infiltration design rates are deferred to Volume 2 Chapter 4 in cited text.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "harris-county-tx", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/harris-county-tx/", "data_url": "https://stormwateratlas.com/data/manuals/harris-county-tx.json", "document_metadata": { "jurisdiction_name": "Harris County", "jurisdiction_level": "county", "state_code": "TX", "document_title": "Harris County Low Impact Development & Green Infrastructure Design Criteria for Storm Water Management", "version_or_edition": "Adopted April 2011", "adoption_or_effective_date": "2011-04-01", "last_revised_date": "2011-04-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Projects exceeding one acre require a Storm Water Quality (SWQ) Permit and SWQMP; treat the first 1 inch of runoff. LID IMPs (bioretention, vegetated swales, permeable pavement, rainwater harvesting, green roofs, filter strips, planters, tree box filters) may satisfy quality and detention credits per Table 1. Conventional gravity detention minimum rate 0.55 ac-ft per acre (Table 3); LID projects may use reduced detention with approved low-impact approach.", "peak_flow_calculation_method": [ "Detention and hydrograph matching per HCPID-AED / HCFCD requirements", "Minimum detention 0.55 ac-ft/acre for gravity systems" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Disconnection of roof runoff and impervious surfaces", "Vegetated filter strip", "Vegetated swale / bioswale", "Rainwater harvesting", "Bioretention systems", "Permeable pavement", "Tree box filter", "Storm water planter box", "Green roof" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Harris County Low Impact Development & Green Infrastructure Design Criteria", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Harris County Flood Control District", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Harris County Low Impact Development & Green Infrastructure Design Criteria for Storm Water Management", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "interim guidelines ... HCPID-AED and HCFCD Storm Water Management Programs", "page_or_section": "Background" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treatment of the first 1\" of runoff ... Storm Water Quality Permit required", "page_or_section": "Table 5 / §2.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The minimum detention rate for gravity drained detention basin systems is 0.55 ac-ft", "page_or_section": "Table 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Roof Runoff & Impervious Surfaces 3.2 Vegetated Filter Strip 3.3 Vegetated Swale 3.4 Rainwater Harvesting 3.5 Bioretention Systems 3.5.1 Requirements 3.5.2 Sizing a Bioretention system 3.5.3 Engineered Soil Media 3.5.4 Underdrain 3.5.5 Observation/Cleanout Pipe 3.5.6 Positive O", "page_or_section": "p. 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = depth of runoff to treat (1\" under these guidelines)", "page_or_section": "3.5.2 Sizing a Bioretention System, page 15" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treatment of the first 1\" of runoff", "page_or_section": "Table 6 / 3.5.1 Requirements, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Ponding duration not to exceed 24 hours.", "page_or_section": "Table 6 Surface Ponding, page 14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "designed so that surface ponding does not exceed 24 hours", "page_or_section": "1.5 Bioretention Systems, page 30" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "capacity to drain the surface of the system within 24 hours", "page_or_section": "1.6.1 Underdrain, page 34" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered Soil Media depth should be determined ... (typically between 18 and 24 inches).", "page_or_section": "1.5.2 Engineered Soil Media, page 31" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Df = engineered soil media depth in Feet (typically 1.5 – 2.0)", "page_or_section": "3.5.2 Sizing a Bioretention System, page 15" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "meet Harris County minimum 30\"/hour Infiltration rate requirements", "page_or_section": "Appendix B, page 42" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "must provide a minimum safety factor of 2", "page_or_section": "3.5.3 Engineered Soil Media, page 15" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "LID/GI design criteria (2011). Full HCFCD PCPM remains portal-gated; this PDF covers SWQ 1\" treatment and LID IMPs used with county detention criteria. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://oce.harriscountytx.gov/Portals/43/Documents/Publications/SWQ_LID_design_criteria.pdf", "landing_page_url": "https://oce.harriscountytx.gov/Services/Consultants-Resources-and-Specifications/Watershed-Protection/LID-Green-Infrastructure", "retrieved_at": "2026-08-10T09:18:00.000Z", "original_filename": "harris-county-tx.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 30, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T08:30:32.712Z", "enrich_model": "composer-2.5:run-35380dbe-fc77-462b-8e98-6ed65ceb7ed0", "enrich_notes": "WQv uses P = 1 inch runoff depth (Vwq = P/12 × A). LID detention features target drain within 72 hours unless pre-existing conditions take longer. Bioretention Table 6 lists max surface ponding 2 ft (2-yr) and 4 ft (100-yr); general text cites ~12–24 in ponding with max duration 24 h. Engineered media Df typically 1.5–2.0 ft; appendix media depth guidance 18–24 in. Design infiltration uses safety factor 2; Appendix B as-built minimum 30 in/hr. Permeable pavement must drain surface within 24 h. Extensive green roofs cite 4–8 in growth media (range, no single design depth). Tree box filters and storm water planters reference bioretention criteria.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "id-itd-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/id-itd-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/id-itd-drainage.json", "document_metadata": { "jurisdiction_name": "Idaho", "jurisdiction_level": "state", "state_code": "ID", "document_title": "ITD Roadway Design Manual Section 600 Hydraulics", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "ITD Roadway Design Manual Section 600 Hydraulics", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "y Methods 625.00- Design Floods 625.01- 100-Year Flood 625.02- Scour Review Flood 630.00- Permits 630.01- Joint Application for", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "10 square miles • NRCS TR-55 Method. • Rational Method. Is generally used for storm sewer design and is limited to small waters", "page_or_section": null } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. ITD Roadway Design Manual Section 600 Hydraulics Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://apps.itd.idaho.gov/apps/manuals/roadwaydesign/files/RoadwayDesign600.pdf", "landing_page_url": "https://apps.itd.idaho.gov/apps/manuals/roadwaydesign/files/Roadwaydesignprintable.pdf", "retrieved_at": "2026-08-11T17:59:10.617Z", "original_filename": "id-itd-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T08:38:05.439Z", "enrich_model": "composer-2.5:run-b4900487-7b4a-41b9-9571-b8d58c91f3f0", "enrich_notes": "ITD Roadway Design Manual Section 600 covers highway hydraulics (culverts, bridges, storm sewers, design floods, permits). Detention/retention facilities are listed among review topics for the Hydraulics Engineer but no SCM/BMP sizing criteria appear in the provided excerpts. Storm sewer design references FHWA HEC-22; technical drainage guidance points to AASHTO Model Drainage Manual (not ITD policy) and ITD self-taught hydrology courses.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "idaho-bmp-catalog", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/idaho-bmp-catalog/", "data_url": "https://stormwateratlas.com/data/manuals/idaho-bmp-catalog.json", "document_metadata": { "jurisdiction_name": "Idaho", "jurisdiction_level": "state", "state_code": "ID", "document_title": "Idaho Catalog of Storm Water Best Management Practices", "version_or_edition": "April 2020", "adoption_or_effective_date": "2020-04", "last_revised_date": "2020-04", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Defer to local flood/WQ design standards when available; otherwise Table 5 guidance: capture first 1/2 inch of runoff (~70–80% of annual runoff volume) or first 1 inch (~90%) as water quality volume / first-flush treatment depth; alternatively require a specified pollutant-removal percentage (e.g., 80% suspended solids). WQv may also be tied to a design storm frequency (6-month, 1-year, or 2-year).", "peak_flow_calculation_method": [ "Rational Method", "NRCS TR-55", "Continuous simulation (HSPF, HEC-HMS, SWMM)", "Degree-day method (snowmelt)", "HEC-HMS energy balance (rain-on-snow)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Site Design BMPs", "Construction BMPs", "Postconstruction BMPs", "Storm Water Filters (biofiltration/bioinfiltration swales, filter strips, media filters, catch-basin inserts)", "Infiltration Facilities (trenches, bioretention, porous pavement, vegetated roofs, planters)", "Detention Facilities (wet ponds, extended detention, constructed wetlands, sedimentation basins, underground detention)", "Other Structural Controls (oil/water separators, vortex separators, level spreaders)", "Source Controls", "Green Infrastructure / Low-Impact Development", "Rainwater Harvesting and Reuse" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "State of Idaho Department of Environmental Quality", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The Idaho Catalog of Storm Water Best Management Practices provides technical guidance for construction site design and selecting storm water best management practices (BMPs) as well as information on permitting requirements for storm water discharges in Idaho.", "page_or_section": "Section 1 Introduction, Page 1" }, { "field": "document_metadata.state_code", "excerpt": "Idaho Department of Environmental Quality Water Quality Division 1410 N. Hilton Boise, ID 83706", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Idaho Catalog of Storm Water Best Management Practices", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "No. 10. http://vwrrc.vt.edu/swc/april_22_2010_update/DCR_BMP_Spec_No_10_DRY_SWALE_Fi nal_Draft_v1-8_04132010.htm Washington State Department of Ecology. 2012. Stormwater Management Manual for Western Washington. Lacey, WA. Publ. 12-10-030. http://www.ecy.wa.gov/programs/w", "page_or_section": "p. 131" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "This 2020 BMP catalog provides updated information on storm water regulations and provides additional technical information on selected BMPs.", "page_or_section": "Section 1.2 Catalog Updates, Page 2" }, { "field": "document_metadata.last_revised_date", "excerpt": "No. 10. http://vwrrc.vt.edu/swc/april_22_2010_update/DCR_BMP_Spec_No_10_DRY_SWALE_Fi nal_Draft_v1-8_04132010.htm Washington State Department of Ecology. 2012. Stormwater Management Manual for Western Washington. Lacey, WA. Publ. 12-10-030. http://www.ecy.wa.gov/programs/w", "page_or_section": "p. 131" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This catalog contains voluntary controls that could be formally adopted by a jurisdiction to establish standards... it is not all-inclusive and should be used with other reference sources published by other agencies as appropriate based on local conditions and policies.", "page_or_section": "Section 1 Introduction / 1.1 Goals and Objectives, Pages 1–2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "While the most frequently used design for flood control and channel protection are the 2-, 10-, and 100-year storms... Table 5. Design storm frequencies... 1 year... 2 year... 10 year... 100 year Used for flood control protection from major storms", "page_or_section": "Table 5 and Section 3.6.1, Pages 52–53" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Use local design standards for flood control and water quality control. If local design standards are not available, Table 5 provides a summary... 1/2 to <1-inch rainfall Intended to capture 70%–80% of annual runoff volume... 1-inch rainfall Intended to capture 90% of annual runoff volume... jurisdictions specify a treatment volume, referred to as the water quality volume... first 1/2-inch, 1-inch, or other rainfall depth... or... 6-month, 1-year, or 2-year frequency storm... must have 80% of suspended solids removed", "page_or_section": "Sections 3.6 / 3.6.2 and Table 5, Pages 52–53" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The rational method and NRCS Technical Release-55 (TR-55) method are simple and widely used for performing single event design storm analysis... continuous simulation models... HSPF... HEC-HMS, and... SWMM... For rain-on-snow events, an energy balance approach using a computer model such as HEC-HMS is recommended... degree-day method", "page_or_section": "Sections 3.6.3–3.6.3.2, Pages 53–59" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "and limitation information as well as design parameters, construction guidelines, and operation and maintenance recommendations. The most important requirements for successful performance of treatment control postconstruction facilities are proper sizing and regular inspection", "page_or_section": "p. 41" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum drawdown time for the flooded depth should be within 72 hours after flow ceases.", "page_or_section": "3.10.2.2 Existing Systems, page 136" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "An acceptable infiltration rate should be greater than 0.4 inches per hour.", "page_or_section": "3.5.1.5 Conveyance, page 37" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Site-specific testing should be conducted to demonstrate site infiltration rates of at least 0.4 inches per hour.", "page_or_section": "3.5.3.1 Treatment Controls, page 42" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min. Ground Water Separation 3 feet", "page_or_section": "BMP 23 Extended Detention Basin, page 216 (Figure 60)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The pond outlet is designed to detain the volume of the water quality design storm runoff for a minimum time (usually 48 hours)", "page_or_section": "BMP 23 Extended Detention Basin, page 216" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "A length-to-width ratio of at least 1.5:1 is recommended to prevent short circuiting.", "page_or_section": "BMP 24 Constructed Wetlands, page 227" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The surface area for the wetland can then be calculated by dividing this volume by 3-feet average water depth.", "page_or_section": "BMP 24 Constructed Wetlands, page 227" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "April 2020 Idaho DEQ BMP catalog is voluntary statewide guidance that defers to local design standards; Table 5 and §3.6 supply default design-storm/WQv/hydrology methods when local standards are absent. Source text includes an explicit truncation marker ([... DOCUMENT TEXT TRUNCATED FOR LENGTH — middle sections omitted ...]) so many middle BMP fact sheets (roughly after rainwater harvesting design detail through later operational BMPs) were not available for review; TOC and early chapters plus §3.6 remain intact.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.aqualisco.com/wp-content/uploads/2019/08/Catalog-of-Stormwater-Best-Management-Practices.pdf", "landing_page_url": "https://www.deq.idaho.gov/water-quality/wastewater/stormwater/", "retrieved_at": "2026-08-10T07:09:00.000Z", "original_filename": "idaho-bmp-catalog.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.4, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": 48, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:38:34.025Z", "enrich_model": "composer-2.5:run-a14166eb-f65c-4c68-a8b7-4bc2a7985f05", "enrich_notes": "Idaho catalog defers WQv to local standards; provided excerpts give bioinfiltration swale 72-h drawdown, infiltration minimum 0.4 in/hr, ED basin 3 ft GW separation and ~48 h WQ detention, constructed wetland L:W ≥1.5 and 3 ft average depth for sizing. Middle BMP fact sheets truncated in source.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "il-idot-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/il-idot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/il-idot-drainage.json", "document_metadata": { "jurisdiction_name": "Illinois", "jurisdiction_level": "state", "state_code": "IL", "document_title": "IDOT Drainage Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS" ], "approved_bmp_categories": [ "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "IDOT Drainage Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "foot above the applicable base flood or 100-year frequency flood elevation. D. \"Office of Water Resources\" means the Illinois De", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Natural Resource Conservation Service (NRCS), National Highway Institute (NHI) and the Federal Highway Administration (FHWA", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "detention basin, retention basin, aggregate filter and manufactured devices", "page_or_section": "Chapter 8, Section 8-306 Best Management Practices, page 482" }, { "field": "practice_mentions.swale", "excerpt": "vegetated swales and buffers", "page_or_section": "Chapter 8, Section 8-306 Best Management Practices, page 482" }, { "field": "practice_mentions.wet_pond", "excerpt": "Retention facilities are designed to contain a permanent pool of water.", "page_or_section": "Chapter 12, Section 12-001 Types, page 649" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "manufactured devices", "page_or_section": "Chapter 8, Section 8-306 Best Management Practices, page 482" }, { "field": "enrich_notes", "excerpt": "The designer should establish pollutant removal goals then design BMPs that achieve those goals. The U.S. Environmental Protection Agency’s National Menu of Storm Water Best Management Practices ... the Illinois Urban Manual (IEPA/USDA, NRCS; latest version), and IDOT BDE Manual, Chapter 59", "page_or_section": "Chapter 8, Section 8-306, page 482" }, { "field": "enrich_notes", "excerpt": "a grade of at least 0.3 percent should be provided on all roadside ditches. Grades in the range of 0.4 percent to 0.6 percent are usually more desirable.", "page_or_section": "Chapter 9, Section 9-302 Considerations, page 501" }, { "field": "enrich_notes", "excerpt": "excavation should be limited to areas outside of the channel bank(s) and above the ground water table and/or the normal water elevation in the stream (or pool) (1 foot minimum is desirable).", "page_or_section": "Chapter 3, Section 3-403.01, page 165" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. IDOT Drainage Manual (July 2011) via PowerDMS Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://public.powerdms.com/IDOT/documents/2084523", "landing_page_url": "https://idot.illinois.gov/doing-business/industry-marketplace/bridges-and-structures-services/specific-scope-of-services.html", "retrieved_at": "2026-08-11T17:59:10.621Z", "original_filename": "il-idot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:39:04.902Z", "enrich_model": "composer-2.5:run-3dc6aa85-aa6c-469e-8a8d-d71d628ae3e4", "enrich_notes": "Excerpts are IDOT highway drainage policy (Ch 1–2, 6–9, 12) and storm-sewer utility separation, not site SCM sizing. Chapter 12 defines detention vs retention and linear oversizing; BMP list (8-306) points to Illinois Urban Manual and BDE Ch 59 for BMP design. Roadside ditch minimum longitudinal grade 0.3% (0.4–0.6% preferred) applies to ditches, not explicitly to vegetated swales. Floodplain storage excavation cites 1 ft minimum above groundwater/normal pool (3-403.01)—not SHWT separation for infiltration SCMs.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "il-iepa-stormwater", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/il-iepa-stormwater/", "data_url": "https://stormwateratlas.com/data/manuals/il-iepa-stormwater.json", "document_metadata": { "jurisdiction_name": "Illinois EPA / Association of Illinois Soil and Water Conservation Districts", "jurisdiction_level": "state", "state_code": "IL", "document_title": "Illinois Urban Manual", "version_or_edition": "June 2013", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration Trench", "Vegetated Swale", "Filter Strip", "Permeable Pavement" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Illinois EPA / Association of Illinois Soil and Water Conservation Districts", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Illinois Urban Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Natural Resources Conservation Service (NRCS) in Illinois. The NRCS was formerly known and recognized as the Soil Conservati", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Trench, Vegetated Swale, Filter Strip, Permeable Pavement", "page_or_section": null }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "wet detention pond with a 4:1 length to width ratio and a mean depth of 4 feet", "page_or_section": "Example 6, pages 106-107" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "wet detention pond with a 4:1 length to width ratio and a mean depth of 4 feet", "page_or_section": "Example 6, pages 106-107 (4 ft mean depth converted to 48 in)" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet ponds or multiple pond systems are the most reliable practices for controlling nutrients in runoff", "page_or_section": "Example 3, page 97" }, { "field": "practice_mentions.extended_detention", "excerpt": "All flows are to be treated by a 100 ft buffer strip with 10% slope and a wet detention pond", "page_or_section": "Example 6, page 106" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Infiltration Trench 847 1/99", "page_or_section": "Section 4, List of Urban Standards (Alphabetical), page 28" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Urban Stormwater Wetlands* 800 8/94", "page_or_section": "Section 4, List of Urban Standards (Alphabetical), page 28" }, { "field": "practice_mentions.swale", "excerpt": "Grass - Lined Channel 840 10/01", "page_or_section": "Section 4, List of Urban Standards (Alphabetical), page 28" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. Illinois Urban Manual (June 2013 PDF compilation via AISWCD; IEPA/partner statewide BMP reference)", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "http://www.aiswcd.org/wp-content/uploads/2013/06/IUM_June20131.pdf", "landing_page_url": "https://aiswcd.org/illinois-urban-manual/", "retrieved_at": "2026-08-11T17:21:06.024Z", "original_filename": "il-iepa-stormwater.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": null, "length_to_width_ratio": 4, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:39:43.642Z", "enrich_model": "composer-2.5:run-15301024-ce3f-4391-83a8-ca3c95a1371c", "enrich_notes": "Provided corpus is largely Table of Contents, Section 2 planning narrative, glossary, and Appendix phosphorus-loading examples (Maine-adapted). Section 4 practice criteria with numeric design standards are not included except the alphabetical standards list (e.g., Infiltration Trench 847, Filter Strip 835, Urban Stormwater Wetlands 800, Grass-Lined Channel 840). Explicit numeric SCM geometry in excerpts appears only in Example 6 (wet detention pond mean depth and L:W ratio).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "in-indot-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/in-indot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/in-indot-drainage.json", "document_metadata": { "jurisdiction_name": "Indiana", "jurisdiction_level": "state", "state_code": "IN", "document_title": "INDOT Design Manual Chapter 203", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "HEC-HMS", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-RAS", "HY-8" ], "approved_bmp_categories": [ "Infiltration Basin", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "INDOT Design Manual Chapter 203", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "esign storm for the main stream and the 100-year design storm for the tributary. The other model will use the 100-year design st", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "logy calculations which can include the Rational Method, Hydrograph Method (TR- 20, HEC-HMS, etc.), curve numbers, Manning’s n v", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Basin, Detention Basin", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The detention basin should drain within 72 hours.", "page_or_section": "203-5.03(02) Detention Basin, page 83" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Design infiltration rates should allow for the basin to fully drain within 72 hours.", "page_or_section": "203-5.04(02) Infiltration Basin, page 88" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The primary outlet should be designed to drain the entire detention volume within 72 hours.", "page_or_section": "203-5.04(01) Detention Basin, page 87" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the infiltration basin should be at least 2 ft above the high-water table.", "page_or_section": "203-5.03(03) Infiltration Basin, page 84" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Additionally, the bottom should be a minimum of 2 ft above the seasonal high-water table from the USDA soil survey data.", "page_or_section": "203-5.04(02) Infiltration Basin, page 88" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Only infiltration rates of at least 2 in. per hour should be used for sizing.", "page_or_section": "203-5.04(02) Infiltration Basin, page 88" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. INDOT Design Manual Chapter 203 — Hydraulics and Drainage Design Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.in.gov/dot/div/contracts/design/Part%202/Chapter%20203%20-%20Hydraulics%20and%20Drainage%20Design.pdf", "landing_page_url": "https://www.in.gov/indot/design-manual/", "retrieved_at": "2026-08-11T17:59:10.583Z", "original_filename": "in-indot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin" ], "enriched_at": "2026-08-13T08:40:29.881Z", "enrich_model": "composer-2.5:run-b9748852-1077-4e2b-a3a9-bb0d6c3c9ed1", "enrich_notes": "Chapter 203 covers highway hydraulics and quantity control (detention/infiltration basins, roadside ditch detention, underground storage). Post-construction water quality is referenced to Chapter 204; no WQv depth in this excerpt. Infiltration minimum rate and 2 ft SHWT separation are sizing/site criteria, not bioretention or MTD.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "indiana-manual", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/indiana-manual/", "data_url": "https://stormwateratlas.com/data/manuals/indiana-manual.json", "document_metadata": { "jurisdiction_name": "Indiana", "jurisdiction_level": "state", "state_code": "IN", "document_title": "Indiana Storm Water Quality Manual", "version_or_edition": "October 2007", "adoption_or_effective_date": "2007-10-01", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Treat at least one-half inch of storm water runoff (water quality volume or storage) from impervious surfaces, targeting removal of at least 80% of total suspended solids on an annual average basis; post-development peak discharge rates and volumes should not exceed predevelopment levels.", "peak_flow_calculation_method": [ "Rational Method", "NRCS Technical Release 55 (TR 55)", "NRCS Technical Release 20 (TR 20)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Swales", "Filter Strip", "Filter Ridge", "Riparian Buffer Zones", "Sand Filters", "Pervious Concrete Systems", "Porous Asphalt Systems", "Porous Paver Systems", "Infiltration Trench", "Infiltration Basin", "Bioretention Systems", "Dry Extended Detention Basins", "Wet Detention Ponds", "Sediment Forebay Ponds", "Constructed Storm Water Wetlands", "Subsurface Detention/Retention", "Gravity Oil-Grit Separators", "Hydrodynamic Separators", "Catch Basin Inserts With Treatment Medium" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "INDIANA STORM WATER QUALITY MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Published October 2007 by the Indiana Department of Environmental Management", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Indianapolis, IN 46204-2251", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "INDIANA STORM WATER QUALITY MANUAL Planning and Specification Guide for Effective Erosion and Sediment Control and Post-Construction Water Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Published October 2007", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Published October 2007", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual is a comprehensive resource of planning principles and standards that can be implemented as land is being developed.", "page_or_section": "Preface" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The two most commonly used storm events are the 10-year frequency, 24-hour duration event and the 100-year frequency, 24-hour duration event.", "page_or_section": "Chapter 3, Storm Water Calculations" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Storm water quality measures selected should be designed to treat at least one-half inch of storm water runoff (water quality volume or storage), at a minimum, from the impervious surfaces. Treatment goals should be targeted to remove at least 80 percent of the total suspended solids from runoff on an annual average basis", "page_or_section": "Chapter 5, Performance Standards" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The basic goal for development is to assure that post-development peak discharge rates and discharge volumes do not exceed the predevelopment levels.", "page_or_section": "Chapter 5, Performance Standards" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Some of the more common and acceptable methods are the rational method, Technical Release Numbers 55 and 20.", "page_or_section": "Chapter 3, Storm Water Calculations" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Trench ... Infiltration Basin ... Bioretention Systems ... Dry Extended Detention Basins ... Wet Detention Ponds ... Constructed Storm Water Wetlands", "page_or_section": "Chapter 8 Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Pervious Concrete Systems ... Porous Asphalt Systems ... Porous Paver Systems ... Sand Filters ... Vegetated Swales", "page_or_section": "Chapter 8 Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Water Quality Volume (WQV). The volume of runoff generated by one inch of rainfall on a site.", "page_or_section": "Appendix A — Glossary, page 734" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first .5 to 1.5 inches of a storm event are typical standards.", "page_or_section": "Infiltration Basin, page 609" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The pond should contain a low-flow drain with an adjustable gate valve allowing for gradual discharge. Recommended drawdown is 24 hours.", "page_or_section": "Wet Detention Ponds, Table 3, page 639" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the bioretention area should be three feet or more above the seasonal high water table", "page_or_section": "Bioretention Systems, page 619" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Water table Bottom of the basin > 3 feet above the seasonal high water table depth", "page_or_section": "Infiltration Basin, Table 2, page 609" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the reservoir should be a minimum of three feet above any limiting layer (e.g., seasonal high water table, glacial till, bedrock).", "page_or_section": "Porous Asphalt Systems, page 577" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Minimum soil bed depth of four feet; adjust depth to plant variety.", "page_or_section": "Bioretention Systems, Table 2, page 620" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "A ponding depth of six to nine inches is recommended.", "page_or_section": "Bioretention Systems, page 619" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Typical dimensions for a bioretention area are 10 feet wide by 20 feet long. Any system wider than 20 feet should be at least twice as long to evenly distribute the flow.", "page_or_section": "Bioretention Systems, page 619" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water is retained during storm events and released into the permanent pool over 12 to 48 hours.", "page_or_section": "Wet Detention Ponds, Table 4, page 640" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate > 0.5 inches/hour but < 3.0 inches/hour", "page_or_section": "Infiltration Trench, Table 2, page 599" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "designed and sized to attenuate and treat a small storm water runoff event (typically 0.5 inch to 1.5 inches).", "page_or_section": "Pervious Concrete Systems, page 560" }, { "field": "practice_mentions.swale", "excerpt": "Dry swales are similar to a bioretention system.", "page_or_section": "Vegetated Swales, page 530" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.inafsm.net/assets/docs/indiana%20storm%20water%20quality%20manual.pdf", "landing_page_url": "https://www.in.gov/idem/stormwater/resources/indiana-storm-water-quality-manual/", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "indiana-manual.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 48, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:41:27.597Z", "enrich_model": "composer-2.5:run-f1cf6711-f847-4375-81b3-3603ff7952f9", "enrich_notes": "WQV is defined in Appendix A as runoff from one inch of rainfall on a site; multiple BMP sections size treatment for small storms typically 0.5–1.5 inches. SHWT separation of three feet appears for bioretention, infiltration basin/trench, porous pavement reservoirs, wet ponds, and constructed wetlands. Bioretention Table 2 also specifies 12–20 inch sand/gravel substrate and 6–9 inch recommended ponding depth. Soil permeability acceptance ranges 0.5–3 in/hr for infiltration BMPs; porous systems cite one-inch first flush for water quality exfiltration. Wet extended detention release to permanent pool is 12–48 hours (Table 4). Shallow marsh depths 6–18 inches in glossary refer to wetland marsh zones, not a single permanent pool depth.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ia-dot-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/ia-dot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ia-dot-drainage.json", "document_metadata": { "jurisdiction_name": "Iowa", "jurisdiction_level": "state", "state_code": "IA", "document_title": "Iowa DOT Design Manual Ch4 Drainage", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "Iowa DOT Design Manual Ch4 Drainage", "page_or_section": "Title / header" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. Iowa DOT Design Manual Ch4 Drainage — §4A-01 intro (chapter set) Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_name", "design_criteria.design_storm_return_periods_years", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://documents.iowa.gov/Home/Download/9592853", "landing_page_url": "https://iowadot.gov/design-manual/chapter-4-drainage", "retrieved_at": "2026-08-11T17:59:10.615Z", "original_filename": "ia-dot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T08:37:14.310Z", "enrich_model": "composer-2.5:run-728dc8db-bf3a-438a-8c2f-48483decd9d1", "enrich_notes": "Section 4A-1 is an introductory overview of roadway stormwater drainage design and the HEC-22 five-step process (data collection, coordination, preliminary layout, hydrologic/hydraulic refinement, documentation). No BMP-specific design criteria or numeric SCM parameters appear in the supplied pages.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ia-state-ch1", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/ia-state-ch1/", "data_url": "https://stormwateratlas.com/data/manuals/ia-state-ch1.json", "document_metadata": { "jurisdiction_name": "Iowa", "jurisdiction_level": "state", "state_code": "IA", "document_title": "Iowa Storm Water Management Manual", "version_or_edition": null, "adoption_or_effective_date": "2009-10-28", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Equivalent to the rainfall depth in inches (using the recommended 90% cumulative frequency depth of 1.25 inches) multiplied by the volumetric runoff coefficient (Rv) for the site and the site drainage area.", "peak_flow_calculation_method": [ "Rational Method", "WinTR-55 Method", "TR-20 Model", "HEC-1", "HEC-HMS", "Regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS", "HEC-2", "SWMM", "WSPRO", "HY-8", "WinTR-55", "HEC-1", "HEC-HMS", "TR-20" ], "approved_bmp_categories": [ "Non-structural BMPs", "Stormwater Detention BMPs", "Infiltration BMPs", "Vegetative BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Iowa Storm Water Management Manual", "page_or_section": "Chapter 1- Section 1, Page 1 of 8" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Iowa Storm Water Management Manual", "page_or_section": "Chapter 1- Section 1, Page 1 of 8" }, { "field": "document_metadata.state_code", "excerpt": "The Nationwide Permit Program Fact Sheet No. 7 (IA)", "page_or_section": "Chapter 1- Section 3, Page 5 of 10" }, { "field": "document_metadata.document_title", "excerpt": "Iowa Storm Water Management Manual", "page_or_section": "Chapter 1- Section 1, Page 1 of 8" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "October 28, 2009", "page_or_section": "Chapter 1- Section 1, Page 1 of 8" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Iowa Storm Water Management Manual", "page_or_section": "Chapter 1- Section 1, Page 1 of 8" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "a. Extended detention of the 1-year, 24-hour storm for a period of 24 hours using structural stormwater controls. It is known that the increase in runoff due to development can dramatically increase stream channel erosion. This standard is intended to reduce the freque", "page_or_section": "p. 38" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "In numerical terms, it is equivalent to the rainfall depth in inches (the 90% cumulative frequency rainfall depth) multiplied by the volumetric runoff coefficient (Rv) for the site, and the site drainage area.", "page_or_section": "Chapter 1- Section 4, Page 2 of 7" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Use the Rational Method for drainage areas up to 160 acres... Use the WinTR-55 Method for drainage areas up to 2000 acres... TR-20 Model... Routines contained in HEC-1 or HEC-HMS computer models... Regression equations", "page_or_section": "Chapter 1- Section 5, Page 2 of 8" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HEC-RAS - river analysis systems... HEC-2 - water surface profiles... SWMM - stormwater management model... WSPRO - water surface profiles... HY-8 - hydraulic design of highway culverts", "page_or_section": "Chapter 1- Section 5, Page 4 of 8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "8 of 10 October 28, 2009 manual. a. Non-structural BMPs. 1) Planning Procedures. Runoff problems can be addressed efficiently with sound planning procedures. Local master plans, comprehensive plans, and zoning ordinances can promote improved water quality in many ways, such a", "page_or_section": "p. 33" }, { "field": "fields_not_found", "excerpt": "Extended detention of the 1-year, 24-hour storm for a period of 24 hours using structural stormwater controls.", "page_or_section": "p38" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The design rainfall event that is recommended for computing the WQv is 1.25 inches and is equal to the 90% cumulative frequency rainfall depth for the area.", "page_or_section": "C1-S4 Stormwater Management Criteria, page 2 of 7 (ia-state-ch1-c0039)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A statewide WQv of 1.25 inches is recommended for use or jurisdictions can use a similar value derived from an analysis of local historical rainfall", "page_or_section": "C1-S4 Stormwater Management Criteria, page 2-3 of 7 (ia-state-ch1-c0039)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended detention of the 1-year, 24-hour storm for a period of 24 hours using structural stormwater controls.", "page_or_section": "C1-S4 Stream channel protection guideline #3a, page 3 of 7 (ia-state-ch1-c0040)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "The listed software are noted in the text as 'typical modeling programs' rather than explicitly 'required'. Version and last revised dates were not explicitly distinguished beyond the general publication date of October 28, 2009.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.iowadnr.gov/media/7380/download?inline=", "landing_page_url": "https://www.iowadnr.gov/environmental-protection/water-quality/stormwater-program/iswmm-manual", "retrieved_at": "2026-08-07T11:37:16.121Z", "original_filename": "ia-state-ch1.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:37:41.067Z", "enrich_model": "composer-2.5:run-822a5d0a-88a2-47d4-b7cd-ef3249c31e9c", "enrich_notes": "Chapter 1 proxy cites statewide WQv design rainfall 1.25 in (90% cumulative frequency) and minimum 0.2 in/ac WQv for drainage areas under 15% impervious; Cpv requires 24-hour extended detention of the 1-year 24-hour storm. Structural BMP sizing details are deferred to Chapter 4.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ks-kdot-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/ks-kdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ks-kdot-drainage.json", "document_metadata": { "jurisdiction_name": "Kansas", "jurisdiction_level": "state", "state_code": "KS", "document_title": "KDOT Drainage Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)", "HEC-HMS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "KDOT Drainage Design Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "free of encroachments, would carry the 100-year flood without substantial increases in flood heights. Flowage Easement – A perm", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "h Culvert CN Runoff Curve Number in the NRCS rainfall-runoff relationship CRP Cross Road Pipe CSMAC Corrugated Steel, Metal", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "1.5.5 Detention-Storage Structures The plans and supporting documents should include the pertinent information regarding detention requirements that impact construction.", "page_or_section": "1.5.5 Detention-Storage Structures, page 1-28" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. KDOT Drainage Design Manual (May 2023) Section 1 Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.ksdot.gov/home/showpublisheddocument/858/638942965857170000", "landing_page_url": "https://www.ksdot.gov/doing-business/design-consultants/design-resources/drainage-design-manual", "retrieved_at": "2026-08-11T17:59:10.623Z", "original_filename": "ks-kdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention" ], "enriched_at": "2026-08-13T08:49:01.747Z", "enrich_model": "composer-2.5:run-e5b4eac1-f81f-4b2f-a948-a677c38d3342", "enrich_notes": "Corpus is largely KDOT Drainage Design Manual Section 1 (intro, symbols, definitions, plan documentation). Section 1.5.5 lists detention-storage plan items (basin volume, normal/low pool, freeboard, length of retention, storm return period) without numeric SCM design criteria. No WQv method, BMP sizing, infiltration rates, or canonical practice design depths in provided excerpts. Subgrade defined as topmost 18 in.—not SHWT separation.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "kentucky-bmp", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/kentucky-bmp/", "data_url": "https://stormwateratlas.com/data/manuals/kentucky-bmp.json", "document_metadata": { "jurisdiction_name": "Kentucky", "jurisdiction_level": "state", "state_code": "KY", "document_title": "BMP Planning and Technical Specifications Manual for Construction Sites in Kentucky", "version_or_edition": "Section 1", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "No statewide post-construction water quality volume formula in this section; Louisville-Jefferson County MSD requires erosion and sediment controls designed for 80% TSS removal using a 10-year, 24-hour storm event, and post-construction treatment controls include infiltration, filtration, and retention or detention facilities per LID principles.", "peak_flow_calculation_method": [ "Hydrologic and hydraulic analysis for 100-year floodplain construction permits" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Land Grading", "Construction Exit", "Temporary Diversion (Berm or Ditch)", "Temporary and Permanent Seeding", "Mulching and Sodding", "Silt Fence", "Brush, Rock, and Sediment Barriers", "Erosion Control Blankets and Turf Reinforcement Mats", "Sediment Traps", "Sediment (Detention) Basins", "Buffer Zones and Filter Strips", "Rock-Lined and Grass-Lined Channels", "Check Dams", "Bioretention and Infiltration (post-construction)", "Good Housekeeping and Spill Prevention" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "BMP Planning and Technical Specifications Manual for Construction Sites in Kentucky", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "funding provided in part by a grant from the U.S. Environmental Protection Agency (EPA) through the Kentucky Division of Water (KDOW)", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Kentucky Division of Water", "page_or_section": "Technical Review Committee" }, { "field": "document_metadata.document_title", "excerpt": "BMP Planning and Technical Specifications Manual for Construction Sites in Kentucky", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Planning and Technical Specifications Manual \u0018 \u0018. Introduction This.Planning.and.Technical.Specifications.Manual.contains.information.on.Best. Management.Practices.(BMPs).for.preventing,.reducing,.and.controlling.erosion,.sediment,. and.pollutant.runoff.from.construction.sites.", "page_or_section": "p. 5" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The manual is consistent with other Kentucky state and local guides that contain information on controlling polluted runoff from construction sites", "page_or_section": "Chapter 1, Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "All erosion protection and sediment control (EPSC) measures must be designed and installed to accomplish an 80 percent design removal efficiency goal for total suspended solids, using a 10-year, 24-hour storm event design.", "page_or_section": "Chapter 2, Louisville-Jefferson County MSD" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "proposed construction in the floodplain ... the 100-year floodplain of all streams in the Commonwealth", "page_or_section": "Chapter 2, Section 2.6 Kentucky Floodplain Construction Permit" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "must be designed and installed to accomplish an 80 percent design removal efficiency goal for total suspended solids, using a 10-year, 24-hour storm event design", "page_or_section": "Chapter 2, Louisville-Jefferson County MSD" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "hydrologic and hydraulic analysis must be performed ... determines the expected 100-year flood heights and the delineation of the floodway", "page_or_section": "Chapter 2, Section 2.6 Kentucky Floodplain Construction Permit" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Silt Fence ... Sediment (Detention) Basins ... Buffer Zones ... Filter Strips ... Rock-Lined Ditches and Channels ... Grass-Lined Ditches and Channels", "page_or_section": "Chapter 4 Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "directing runoff into bioretention and infiltration areas before it leaves the lot", "page_or_section": "Chapter 3, Section 3.3 Post-Construction Stormwater Management" }, { "field": "practice_mentions.swale", "excerpt": "Many BMPs can serve both functions if designed and implemented properly (i.e. a grassy swale can filter runoff while directing it away from a denuded area).", "page_or_section": "Section 3 / page 23 (kentucky-bmp-c0023)" }, { "field": "practice_mentions.swale", "excerpt": "Ditches, swales, berms, dikes, or pipes can be used to channel flow away from disturbed areas.", "page_or_section": "Section 3 / page 24 (kentucky-bmp-c0024)" }, { "field": "practice_mentions.extended_detention", "excerpt": "4.7.2 Sediment (Detention) Basins — Trap sediment by collecting it in a basin and slowly discharging it. Required for disturbed drainage areas of more than 10 acres.", "page_or_section": "Section 4 BMP table / page 40 (kentucky-bmp-c0053)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention basins, if used, must be constructed first and must perform as sediment basins until the contributing drainage area is seeded and stabilized.", "page_or_section": "Section 3.6 Standard Notes / page 33 (kentucky-bmp-c0033)" }, { "field": "enrich_notes", "excerpt": "Traps and basins are sized to provide 3,600 cubic feet of total storage per disturbed acre.", "page_or_section": "Case Study KYTC phasing / page 17-18 (kentucky-bmp-c0018)" }, { "field": "enrich_notes", "excerpt": "All EPSC measures must be designed and installed to accomplish an 80 percent design removal efficiency goal for total suspended solids, using a 10-year, 24-hour storm event design.", "page_or_section": "Section 2.2 MSD / page 11 (kentucky-bmp-c0012)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "This PDF is KYTC BMP Manual Section 1 only—focused on construction-site BMP planning and technical specifications rather than statewide post-construction hydrologic sizing; local programs (MSD, LFUCG) carry additional quantitative standards. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://transportation.ky.gov/EnvironmentalAnalysis/Environmental%20Resources/KY%20BMP%20Manual%20Section%201.pdf", "landing_page_url": "https://transportation.ky.gov/EnvironmentalAnalysis/Pages/default.aspx", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "kentucky-bmp.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T08:46:21.820Z", "enrich_model": "composer-2.5:run-9e1839cf-897d-4f94-a081-63daa3804b7c", "enrich_notes": "Kentucky Construction Site BMP Manual (Section 1) focuses on construction-phase erosion and sediment control, not statewide post-construction hydrologic sizing. Louisville-Jefferson County MSD requires EPSC for 80% TSS removal using a 10-year, 24-hour storm (MSD Design Manual referenced, not detailed here). KYTC DDA approach sizes traps/basins to 3,600 cubic feet total storage per disturbed acre; sediment detention basins required when disturbed drainage area exceeds 10 acres. No explicit WQv depth, infiltration design rate, bioretention media/ponding depths, or other post-construction SCM numeric standards appear in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ky-kytc-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/ky-kytc-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ky-kytc-drainage.json", "document_metadata": { "jurisdiction_name": "Kentucky", "jurisdiction_level": "state", "state_code": "KY", "document_title": "KYTC Drainage Guidance Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "HEC-RAS" ], "approved_bmp_categories": [ "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "KYTC Drainage Guidance Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "loodplain.  The predicted value of the 100-year (or “base”) flood serves as the present engineering standard for evaluating flo", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ational Resources Conservation Service (NRCS) NRCS has developed hydrologic and hydraulic-related programs, such as the TR-5", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin, Retention Basin", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "In some instances, this will require the use of energy dissipaters and detention basin storage prior to discharging onto adjacent property.", "page_or_section": "DR-103.3 KENTUCKY TRANSPORTATION CABINET (KYTC), page 6" }, { "field": "practice_mentions.extended_detention", "excerpt": "DR 900: Storage. Design criteria and procedures for reducing peak flows via storage methods such as culvert sizing and detention/retention basins.", "page_or_section": "DR-101.2 LOCATING INFORMATION, page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. KYTC Drainage Guidance Manual — DR-100 Introduction (chapter set) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://transportation.ky.gov/Highway-Design/Drainage%20Manual/DR%20100%20Introduction%20(Draft).pdf", "landing_page_url": "https://transportation.ky.gov/Highway-Design/Pages/Drainage.aspx", "retrieved_at": "2026-08-11T17:59:10.602Z", "original_filename": "ky-kytc-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention" ], "enriched_at": "2026-08-13T08:49:34.408Z", "enrich_model": "composer-2.5:run-e4c2a0bc-f8cf-4cf3-bc50-79bf597b953d", "enrich_notes": "Provided excerpts are DR-100 Introduction (policies, review process, resources). No SCM sizing criteria. DR 900 Storage (detention/retention basin design) is referenced in the table of contents but not included in corpus. Post-development discharge policy mentions detention basin storage as a possible measure.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "king-county-wa", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/king-county-wa/", "data_url": "https://stormwateratlas.com/data/manuals/king-county-wa.json", "document_metadata": { "jurisdiction_name": "King County", "jurisdiction_level": "county", "state_code": "WA", "document_title": "Surface Water Design Manual", "version_or_edition": "2021 Amended November 14, 2024", "adoption_or_effective_date": "2021-07-23", "last_revised_date": "2024-11-14", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Core Requirement #8: Water Quality. Water quality menus (Basic Water Quality Menu and others) in Chapter 6. Continuous simulation / WWHM-based sizing typical for flow control and WQ facilities.", "peak_flow_calculation_method": [ "Core Requirement #3: Flow Control", "Flow Control Design standards (Chapter 3)", "Flow control design using continuous hydrologic modeling (WWHM)", "Core Requirement #9: Flow Control BMPs (dispersal/infiltration LID BMPs)" ], "required_hydrologic_hydraulic_software": [ "Western Washington Hydrology Model (WWHM) / continuous simulation tools as specified" ], "approved_bmp_categories": [ "Flow control facilities", "Water quality treatment facilities (Basic WQ menu and others)", "Flow control BMPs / LID", "Infiltration facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "KING COUNTY, WASHINGTON", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "SURFACE WATER DESIGN MANUAL", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "July 23, 2021 Amended November 14, 2024", "page_or_section": "Title" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "July 23, 2021", "page_or_section": "Title" }, { "field": "document_metadata.last_revised_date", "excerpt": "Amended November 14, 2024", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "King County Code (KCC) Chapter 9.04", "page_or_section": "Chapter 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Flow Control / design standards", "page_or_section": "Chapter 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Core Reqmt #8: Water Quality", "page_or_section": "Section 1.2.8" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Core Reqmt #3: Flow Control", "page_or_section": "Section 1.2.3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Flow Control Design Using the", "page_or_section": "Section 3.3.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Basic Water Quality Menu", "page_or_section": "Section 6.1.1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum allowable drawdown time of the water storage area is 24 hours.", "page_or_section": "Appendix C.2.6.1 Minimum Design Requirements (C-77)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The water storage area, containing the minimum required storage volume, shall be 6-12 inches deep at overflow", "page_or_section": "Appendix C.2.6.1 (C-77)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The designed depth of ponding (6\" minimum to 12\" maximum) must be considered in light of the drawdown time requirement", "page_or_section": "Appendix C.2.6.1 (C-77)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "MIN. 1' ABOVE SEASONAL HIGH GROUNDWATER TABLE, SEE SECTION C.2.2.2", "page_or_section": "Appendix C Figure C.2.2.A–D (C-53 to C-56)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Where the minimum vertical separation of 1 foot to the seasonal high water table, bedrock, or other impervious layer would not be achieved below bioretention", "page_or_section": "Appendix C bioretention suitability (C-76)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "12 inches per hour is the initial uncorrected rate for both standard and high performance BSMs. A corrected design rate of 3 inches per hour is used where the drainage area to the bioretention device exceeds any of the following... A corrected design rate of 6 inches per hour is used if the contributing drainage area does not exceed any of the above-listed areas", "page_or_section": "Section 5.2.1 Design Infiltration Rate – Bioretention and Permeable Pavement (5-48)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "King County SWDM 2021/2024; text extract truncated but core requirements and WQ/flow-control structure clear. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "document_metadata.jurisdiction_level", "document_metadata.state_code" ] }, "source": { "document_url": "https://your.kingcounty.gov/dnrp/library/water-and-land/stormwater/surface-water-design-manual/2021/amended-2024/2021-kcswdm-amended-2024-full-manual.pdf", "landing_page_url": "https://kingcounty.gov/en/dept/dnrp/nature-recreation/environment/water/stormwater", "retrieved_at": "2026-08-10T08:03:22.623Z", "original_filename": "king-county-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:47:49.266Z", "enrich_model": "composer-2.5:run-8fc44862-bdf0-4ec6-a149-bc968e370e16", "enrich_notes": "King County sizes WQ via Core Requirement #8 and Chapter 6 menus; excerpts emphasize continuous simulation/WWHM rather than a single WQv depth. Bioretention flow-control BMP uses region/soil-specific equivalent storage depths (e.g. 0.6–1.9 in till), distinct from a manual WQv inch depth. Infiltration Section 5.2.1 also requires 3 ft (36 in) or 5 ft (60 in) separation to max wet-season groundwater depending on mounding analysis; Appendix C trench/drywell figures show min 1 ft (12 in) above seasonal high groundwater. BSM corrected design infiltration rates of 3 and 6 in/hr and initial 12 in/hr uncorrected are both explicit for bioretention/permeable pavement LID.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "lexington-ky", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/lexington-ky/", "data_url": "https://stormwateratlas.com/data/manuals/lexington-ky.json", "document_metadata": { "jurisdiction_name": "Lexington-Fayette Urban County Government", "jurisdiction_level": "municipality", "state_code": "KY", "document_title": "Stormwater Manual", "version_or_edition": "2026 (effective May 1, 2026)", "adoption_or_effective_date": "2026-05-01", "last_revised_date": "2026-05-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "New development: Water Quality Volume — all runoff from impervious areas must pass through a stormwater control sized for the 90th percentile storm of 1.2 inches. Runoff Reduction — green infrastructure shall retain on-site a portion of runoff from impervious areas. Streambank protection: 24-hour detention of runoff volume for the 10-year 6-hour storm. Redevelopment criteria in Section 1.8 (20% reduction / treatment of baseline impervious).", "peak_flow_calculation_method": [ "Post-construction water quantity and quality criteria (Table 1-2)", "Detention for 10-year and 100-year development levels as specified", "100-year floodplain construction criteria" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure practices", "Extended detention basins", "Underground detention", "Post-construction BMPs (Chapter 10)", "Sediment ponds" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "LFUCG STORMWATER MANUAL", "page_or_section": "Header" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Lexington-Fayette", "page_or_section": "Manual" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANUAL", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "LFUCG Stormwater Manual", "page_or_section": "Title" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-year, 100-year", "page_or_section": "Quantity criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "stormwater control sized for the 90th percentile storm of 1.2 inches", "page_or_section": "Section 1.7.3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "24-hour detention of the runoff volume for the 10-year 6-hour storm", "page_or_section": "Section 1.7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "GREEN INFRASTRUCTURE PRACTICES / extended detention basins", "page_or_section": "Table 1-7 / Chapter 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The 90th percentile storm in Fayette County is 1.2 inches. The WQV is determined by multiplying 1.2 inches times the impervious area.", "page_or_section": "10.2.2 / page 138" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Multiply 1.2 inches times the total impervious area", "page_or_section": "1.7.3 / page 23" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain Time: Maximum drain time (i.e., ponding) is 24 hours.", "page_or_section": "10.3.2 Bioretention / page 140" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Provide a planting soil bed with a minimum width of 4 feet and a minimum depth of 4 feet (including a 12-inch sand bed).", "page_or_section": "10.3.2 Design Criteria / page 141" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Grade the top of the planting soil bed to provide a shallow ponding area with a maximum depth of 6 inches.", "page_or_section": "10.3.2 Design Criteria / page 141" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "An underdrain shall be provided if the underlying soils have an infiltration rate of less than 0.5 inches per hour.", "page_or_section": "10.3.2 / page 140" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration basins may be used in locations that have at least 5 feet of soil, with a permeability of at least 0.5 inches/hour underlying the device.", "page_or_section": "10.3.5 Design Criteria / page 149" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Design the extended detention outlet so that the \"design\" WQV requires a maximum of 24 hours to discharge.", "page_or_section": "10.6.2 Design Criteria / page 166" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Provide a minimum length to width ratio of 3:1 or provide gabion baffles", "page_or_section": "10.7.2 Design Criteria / page 168" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "For widths greater than 10 feet, maintain at least a 2:1 length to width ratio.", "page_or_section": "10.3.2 / page 141" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Design the extended detention outlet so that a maximum of 24 hours would be required to release the design WQV.", "page_or_section": "10.9.2 Design Criteria / page 173" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Vegetated Roofs Soil area x soil depth x 0.18. Maximum soil depth for calculation purposes shall be 12 inches.", "page_or_section": "Table 1-7 / page 23" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "LFUCG Stormwater Manual 2026 effective May 1, 2026. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://content.lexingtonky.gov/sites/default/files/2026-04/LFUCG%20Stormwater%20Manual%2005.01.26.pdf", "landing_page_url": "https://www.lexingtonky.gov/government/departments-programs/environmental-quality-public-works/water-quality/municipal-separate-storm-sewer-system-ms4", "retrieved_at": "2026-08-10T08:18:32.603Z", "original_filename": "lexington-ky.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 48, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 3, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 12, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:57:46.740Z", "enrich_model": "composer-2.5:run-29e6f8ea-ca7b-4d08-b0b4-4dfb1be62301", "enrich_notes": "Runoff reduction design volume is 0.8 inches × impervious area (Section 1.7.4). Bioretention total soil-media drawdown may take up to 3 days (72 hours) in addition to 24-hour surface ponding limit. Bioretention requires at least 2:1 length-to-width ratio when filter width exceeds 10 feet; constructed wetlands require at least 2:1. Wet pond permanent pool average depth is 3–6 ft (36–72 in), max 8 ft; ED/wetland marsh permanent pools are stated as 6–12 in. Tree trenches require underdrain if native infiltration is less than 2 in/hr (other GI uses 0.5 in/hr threshold).", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "la-ladotd-drainage", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/la-ladotd-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/la-ladotd-drainage.json", "document_metadata": { "jurisdiction_name": "Louisiana", "jurisdiction_level": "state", "state_code": "LA", "document_title": "LADOTD Hydraulics Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "LADOTD Hydraulics Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "---- 1 – 2 1.3.1 Determination of 25 or 50 Year Frequency ------------------------------------ 1 – 2 1.3.2 Other Conditions to", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "--------------------------- 3 – 2 3.4.3 Rational Method ------------------------------------------------------------------- 3 –", "page_or_section": null }, { "field": "practice_mentions.swale", "excerpt": "profiles of ground elevations ... whether gutter (or swale ditch) grades are low enough to provide for drainage", "page_or_section": "2.6.3 Plan / Profile Sheets (page 29)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. LADOTD Hydraulics Manual (2011) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://dotd.la.gov/media/gyzjm1fu/hydraulics-manual.pdf", "landing_page_url": "https://dotd.la.gov/about/office-of-project-delivery/engineering/public-works/hydraulics/", "retrieved_at": "2026-08-11T17:59:10.560Z", "original_filename": "la-ladotd-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T08:50:01.982Z", "enrich_model": "composer-2.5:run-736cf637-9fea-4c57-be89-b7f00d0148c1", "enrich_notes": "Provided excerpts are preface, table of contents, NRCS peak-runoff soil groups, cross-drain headwater limits, and bridge scour—not stormwater BMP/SCM sizing chapters. No WQv depth, drawdown, SHWT separation, or canonical BMP dimension criteria appear in this corpus. NRCS Table 3-B.6-1 lists hydrologic soil group water-transmission ranges (e.g. Group A >0.30 in/hr) for runoff estimation, not an explicit SCM design infiltration rate.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "louisville-ky", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/louisville-ky/", "data_url": "https://stormwateratlas.com/data/manuals/louisville-ky.json", "document_metadata": { "jurisdiction_name": "Louisville and Jefferson County Metropolitan Sewer District", "jurisdiction_level": "special_district", "state_code": "KY", "document_title": "MSD Design Manual", "version_or_edition": "Rev. 06-29-2021", "adoption_or_effective_date": null, "last_revised_date": "2021-06-29", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Stormwater quality and quantity criteria are addressed in MSD Design Manual Chapter 10 (stormwater). Prepared text extract is truncated; confirm WQv / water quality BMP sizing from full PDF Chapter 10.", "peak_flow_calculation_method": [ "10-year and 100-year conveyance/detention design storms referenced in Chapter 10", "MSD stormwater design criteria for drainage systems and detention" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention", "Stormwater BMPs (per Chapter 10)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Metropolitan Sewer District", "page_or_section": "Title / headers" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "MSD Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "Design Manual", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "MSD Design Manual Chapter 10 stormwater", "page_or_section": "Chapter 10" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "systems will be designed for the 10-year event. The 100-year discharge elevation must be checked to ensure the system does not surcharge out of any inlets and/or manholes. Manning's Equation is recommended to calculate pipe flow and velocity. The storm sewer hydraulic grad", "page_or_section": "pp. 165–166" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "stormwater quality", "page_or_section": "Chapter 10" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Detention basins shall be fully discharged, or return to normal pool elevation in the case of wet basins, within 36 hours after the storm event", "page_or_section": "10.3.8.2 g" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "For mosquito control, BMPs must be designed to have no ponding or standing water within 36 hours of a rainfall event.", "page_or_section": "18.2.3.9" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Where a high water table occurs (vertically) within two feet of the plane of infiltration (bottom of BMP), infiltration shall not be considered", "page_or_section": "18.2.3.5" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The groundwater table shall be at least 2 feet, preferably 4 feet, below the bottom of the rain garden or bioswale.", "page_or_section": "18.4.1.2" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Minimum engineered soil depth is 36 inches.", "page_or_section": "18.4.1.3.9" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "typical ponding depth is 4 inches minimum to 12 inches", "page_or_section": "Table 18.3" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum average infiltration rate for all infiltrating practices shall be 0.5 inches/hour.", "page_or_section": "18.2.3.4" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Retention basins (permanent pools basins or wet basins) shall have a minimum depth of 5'.", "page_or_section": "10.3.8.1 i" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Detention basins shall be fully discharged, or return to normal pool elevation in the case of wet basins, within 36 hours after the storm event", "page_or_section": "10.3.8.2 g" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "basins must have a length to width ratio of at least 2:1, with 3:1 preferred.", "page_or_section": "18.4.4.3.2 Conveyance" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "For bioswales, minimum slope of 1% unless an underdrain is installed.", "page_or_section": "Table 18.3 Longitudinal Slope" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Extensive roofs have soil depths of six inches or less that is designed to support dense, low growing, drought tolerant vegetation.", "page_or_section": "18 Definitions" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Large MSD Design Manual; queue text truncated. Re-extract Chapter 10 from full PDF for higher-confidence WQ and peak methods. Pipeline excerpt repair removed 5 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://louisvillemsd.org/sites/default/files/inline-files/designmanual_rev%2006-29-2021_0.pdf", "landing_page_url": "https://louisvillemsd.org/what-we-do/stormwaterdrainage/drawings", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "louisville-ky.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 36, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 36, "bioretention_ponding_depth_inches": 4, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 36, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 1, "green_roof_media_depth_inches": 6, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:00:45.301Z", "enrich_model": "composer-2.5:run-7f53f0fc-236e-459a-ab2f-913312b1d0d4", "enrich_notes": "WQv sizing uses VR/RE volume steps in Ch. 18; excerpt lacks explicit WQ rainfall depth in inches. Bioretention ponding stated as 4–12 in typical; min media 36 in. SHWT min 2 ft (24 in) below infiltration plane/bottom; 4 ft preferred for rain gardens. Green roof glossary: extensive soil ≤6 in. Permeable paver base depth sized to VR—no fixed inch depth in excerpt. Constructed wetland zones 0–6 in and 6–12 in shallow/deep marsh—not permanent pool depth for wet pond.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "macon-ga", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/macon-ga/", "data_url": "https://stormwateratlas.com/data/manuals/macon-ga.json", "document_metadata": { "jurisdiction_name": "Macon", "jurisdiction_level": "municipality", "state_code": "GA", "document_title": "Georgia Stormwater Management Manual (Macon-Bibb adopts GSMM)", "version_or_edition": "2016 Edition", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 100 ], "water_quality_volume_method": "Sized to treat the runoff from 85% of the storms that occur in an average year, which equates to 1.2 inches of rainfall (Water Quality Volume, WQv), or the first 1.0 inch of rainfall using runoff reduction practices to the maximum extent practicable. If the entire 1.0 inch is reduced, the water quality volume may be waived. Otherwise, the remaining runoff from the 1.2-inch event must be treated to remove at least 80% of average annual TSS.", "peak_flow_calculation_method": [ "SCS Curve Number Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention Basin", "Bioslopes", "Dry Wells", "Infiltration Trenches", "Organic Filters", "Regenerative Stormwater Conveyance", "Sand Filters", "Stormwater Planters/Tree Boxes", "Downspout Disconnects", "Site Reforestation/Revegetation", "Soil Restoration", "Vegetated Filter Strips", "Dry Detention Basins", "Dry Extended Detention Basins", "Multi-Purpose Detention Basins", "Stormwater Ponds", "Stormwater Wetlands", "Gravel Wetlands", "Enhanced Dry Swales", "Enhanced Wet Swales", "Grass Channels", "Gravity Separators", "Proprietary Systems", "Underground Detention", "Green Roofs", "Permeable Paver System", "Pervious Concrete", "Porous Asphalt", "Rainwater Harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Macon adopts GSMM technical standards", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Lilburn Lithonia Lovejoy Macon-Bibb County Marietta Morrow Norcross Palmetto Pine Lake Pooler Port Wentworth Powder Springs Richmond County Riverdale Roswell Savannah Smyrna Snellville Stone Mountain Sugar Hill Suwanee Thunderbolt Tybee Union City", "page_or_section": "p. 39" }, { "field": "document_metadata.state_code", "excerpt": "GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT MANUAL GEORGIA VOLUMES 1 & 2", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2016 EDITION", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-year, 25-year, and 100-year return intervals... 2-year through the 25-year return frequency storm events", "page_or_section": "105, 112" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater management systems shall be designed to retain or treat the runoff from 85% of the storms that occur in an average year, and reduce average annual post-development total suspended solids loadings by 80%. Averaged from rainfall events across the state of Georgia, this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events.", "page_or_section": "111" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "What is the SCS curve number for this sub-watershed", "page_or_section": "154" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention Basin; Bioslopes; Dry Wells; Infiltration Trenches; Organic Filters; Regenerative Stormwater Conveyance; Sand Filters; and Stormwater Planters/Tree Boxes", "page_or_section": "199" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the water quality volume (WQv), which is equal to the runoff generated on a site from 1.2 inches of rainfall", "page_or_section": "VOL 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "this equates to treating storm events of 1.2 inches or less, as well as the first 1.2 inches of runoff for all larger storm events", "page_or_section": "VOL 1, Standard #4 – Water Quality, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "24-hour extended detention storage of the 1-year, 24-hour return frequency storm event", "page_or_section": "VOL 1, Standard #5 – Stream Channel Protection, page 120" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "extended detention of the 1-year, 24-hour storm for a period of 24 hours using BMPs", "page_or_section": "VOL 1, Standard #5 – Stream Channel Protection, page 120" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Municipality coverage via GSMM 2016. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://documents.atlantaregional.com/gastormwater/GSMM_2016%20EDITION_FINAL_V1.pdf", "landing_page_url": "https://atlantaregional.org/what-we-do/natural-resources/georgia-stormwater-management-manual/", "retrieved_at": "2026-08-10T09:29:55.327Z", "original_filename": "macon-ga.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:02:47.656Z", "enrich_model": "composer-2.5:run-fc67b4f7-d331-4846-904e-4151bcceaabf", "enrich_notes": "Macon-Bibb adopts GSMM Vol. 1 excerpts. WQv is runoff from 1.2 in rainfall with 80% TSS removal; runoff reduction targets first 1.0 in on-site (waives WQ treatment if fully achieved). Stream channel protection includes 24-hr extended detention of 1-year, 24-hr storm. Detailed BMP sizing is referenced to Volume 2 Section 4.2 (not in corpus). Permanent stormwater infiltration basins prohibited in high pollution susceptibility groundwater recharge areas.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "maine-manual", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/maine-manual/", "data_url": "https://stormwateratlas.com/data/manuals/maine-manual.json", "document_metadata": { "jurisdiction_name": "Maine", "jurisdiction_level": "state", "state_code": "ME", "document_title": "Maine Stormwater Management Design Manual, Volume III – Technical Design Manual", "version_or_edition": "May 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-05-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25 ], "water_quality_volume_method": "Treat the first 1 inch of runoff from impervious surfaces and 0.4 inch from landscaped areas.", "peak_flow_calculation_method": [ "Rational Method", "SCS TR-20", "SCS TR-55" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Detention Basins for Flooding Control", "Wet Ponds", "Vegetated Buffers", "Infiltration BMPs", "Filtration BMPs", "Conveyance and Distribution Systems", "Separator BMPs", "LID Practices and Techniques" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "MAINE STORMWATER MANAGEMENT MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "MAINE DEPARTMENT OF ENVIRONMENTAL PROTECTION", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Augusta, Maine 04333-0017", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "MAINE STORMWATER MANAGEMENT DESIGN MANUAL Volume III – Technical Design Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "This May 2016 edition supersedes these manuals", "page_or_section": "Acknowledgments" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual is intended to be a guidance document for the design and implementation of sound technical stormwater management systems", "page_or_section": "Disclaimer" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "treat the first 1 inch of runoff from impervious surfaces", "page_or_section": "Chapter 2.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "control the peak flow discharges from the 2, 10 and 25-year 24-hour storms", "page_or_section": "Chapter 2.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater management facilities must be designed to treat the first 1 inch of runoff from impervious surfaces and 0.4 inch from landscaped areas.", "page_or_section": "Chapter 2.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "familiarity with the Rational Method, SCS TR-20 and SCS TR-55 methodology", "page_or_section": "Chapter 2" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "familiarity with the Rational Method, SCS TR-20 and SCS TR-55 methodology", "page_or_section": "Chapter 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 3 Detention Basins for Flooding Control ... Chapter 6 Infiltration BMPs ... Chapter 7 Filtration BMPs ... Chapter 10 LID Practices and Techniques", "page_or_section": "Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "An underdrained soil filter must detain and filter a runoff volume equal to 1.0 inch times the subcatchment's impervious area plus 0.4 inch times the subcatchment's landscaped developed area.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A filter basin must drain dry in no less than 24 and no more than 48 hours.", "page_or_section": "Chapter 7.1, page 50" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the constructed basin, including any underdrain soil filters should be one (1) foot above the seasonal high groundwater table", "page_or_section": "Chapter 3, page 16" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The soil filter over the gravel underdrain pipe bedding must be at least 18 inches deep", "page_or_section": "Chapter 7.2, page 58" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The peak water quality storage depth should not exceed 6 inches over a bioretention basin filter.", "page_or_section": "Chapter 7.2, page 57" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Recommended infiltration should be less than 2.41 inches per hour but great enough that one inch of stored precipitation infiltrates in 24 hours (i.e. >0.04 inches per hour).", "page_or_section": "Chapter 7.7, page 84" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Provide a long and narrow basin shape, with a minimum 2:1 length to width ratio (3:1 is best).", "page_or_section": "Chapter 4 Wet Ponds, page 22" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "The target detention time for the treatment volume should be between 24 to 48 hours.", "page_or_section": "Chapter 7.4 Gravel Wetlands, page 70" }, { "field": "design_parameters.green_roof_slope_percent", "excerpt": "A minimum slope of 2% is considered normal for extensive and simple intensive greening.", "page_or_section": "Chapter 7.6, page 77" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of the underdrained soil filter should be a minimum of 18 inches above the seasonal high groundwater table or bedrock", "page_or_section": "Chapter 7.1, page 50" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://www.maine.gov/dep/land/stormwater/stormwaterbmps/vol3/volume%20III%20May%202016.pdf", "landing_page_url": "https://www.maine.gov/dep/land/stormwater/stormwaterbmps/", "retrieved_at": "2026-08-08T00:57:16.365Z", "original_filename": "maine-manual.extraction.json" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2.41, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": 48, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": 2, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:04:02.140Z", "enrich_model": "composer-2.5:run-9ac39e65-2b0c-426f-842c-2b640ad5b38e", "enrich_notes": "WQv sizing uses 1.0 in on impervious and 0.4 in on landscaped/developed pervious area (composite volume, not a single depth). SHWT separation varies by BMP: 12 in (1 ft) for detention basins, bioretention, subsurface sand filters; 18 in minimum for grassed underdrained soil filters. Gravel wetlands target 24–48 h detention for WQ volume. Infiltration design cites <2.41 in/hr and >0.04 in/hr so 1 in drains within 24 h. Pervious surfaces: 8 in min filter layer (infiltration) and 4 in min filter bed (underdrained storage/filtration)—no single storage-depth parameter extracted. Proprietary systems use Maine DEP Appendix B approval letters, not TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "mtd_verification_program" ] } }, { "slug": "me-dot-drainage", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/me-dot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/me-dot-drainage.json", "document_metadata": { "jurisdiction_name": "Maine", "jurisdiction_level": "state", "state_code": "ME", "document_title": "MaineDOT Highway Program §7 Drainage Design Practices & Procedures", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HydroCAD" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "MaineDOT Highway Program §7 Drainage Design Practices & Procedures", "page_or_section": "Title / header" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MaineDOT Highway Program §7 Drainage Design Practices & Procedures (2021) Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name", "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method" ] }, "source": { "document_url": "https://www.maine.gov/tools/whatsnew/attach.php?id=816916&an=1", "landing_page_url": "https://www.maine.gov/dot/programs-services/highway/highway-engineering", "retrieved_at": "2026-08-11T17:59:10.624Z", "original_filename": "me-dot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T09:07:39.294Z", "enrich_model": "composer-2.5:run-0fe020d5-6e47-4f4c-915d-c4dae649e67f", "enrich_notes": "Provided corpus excerpts (pages 10–13) cover MaineDOT Highway Program §7 catch basin placement, closed drainage systems, and pavement hydraulics (10-year Q10, allowable spread Table 7-5.01). No canonical SCM/BMP chapters or water-quality volume criteria appear in this slice.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "maricopa-county-az", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/maricopa-county-az/", "data_url": "https://stormwateratlas.com/data/manuals/maricopa-county-az.json", "document_metadata": { "jurisdiction_name": "Maricopa County / Flood Control District of Maricopa County", "jurisdiction_level": "county", "state_code": "AZ", "document_title": "Drainage Policies and Standards Manual for Maricopa County", "version_or_edition": "Revised August 22, 2018 (document center label Nov 2025)", "adoption_or_effective_date": "2018-08-22", "last_revised_date": "2018-08-22", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Policy 3.6.6 First Flush: retain or treat the first 0.5 inches of direct runoff. Standard 6.10.2 Minimum Design Storm: new developments shall retain stormwater runoff from a 100-year, 2-hour duration storm (retention volume uses P = 100-year, 2-hour rainfall depth). Use with Drainage Design Manual for Maricopa County (Hydrology/Hydraulics/Erosion Control).", "peak_flow_calculation_method": [ "100-year floodplain / base flood elevation definition", "Design storm duration criteria (Table 6.2; 6- and 24-hour storms)", "Retention basin percolation design factors (Tables 6.14–6.16)", "Detention basin alternative standards (Standard 6.10.4)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention basins", "Detention basins", "First flush / green infrastructure", "Stormwater storage facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Maricopa County", "page_or_section": "Title" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Maricopa County", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Arizona / ADWR State Standard 8-99", "page_or_section": "References" }, { "field": "document_metadata.document_title", "excerpt": "Drainage Policies and Standards Manual for Maricopa County", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised August 22, 2018", "page_or_section": "Header" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised August 22, 2018", "page_or_section": "Header" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised August 22, 2018", "page_or_section": "Header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Drainage Design Manual for Maricopa County (DDM)", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year, 2-hour duration storm", "page_or_section": "Standard 6.10.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "shall make provisions to retain the stormwater runoff from a 100-year, 2-hour duration storm", "page_or_section": "Standard 6.10.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention basins / Detention Basin Requirements", "page_or_section": "Standards 6.10.x" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first flush is defined as the first one-half (1/2) inch of direct runoff from the contributing drainage basin.", "page_or_section": "Glossary, page 151" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Analysis confirming basin draining within 36 hours of the end of the design precipitation event is required.", "page_or_section": "6.14.3 Additional Report Requirements, page 131" }, { "field": "practice_mentions.swale", "excerpt": "Interceptor channels (and other low impact development techniques, such as: bioswales, microbasins) may be required/needed", "page_or_section": "page 140" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Section 323 allows for the use of pervious concrete. Per Section 323 pervious concrete \"is usually part of a water management system used to reduce runoff rates and volumes\"", "page_or_section": "Summary of Changes 6th Edition Draft, Section 2.7.4, page 195" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "SECTION 6: RETENTION BASINS ... Have stormwater storage and first flush requirements been met?", "page_or_section": "Checklist 1, page 157" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "County policies/standards; technical hydrology in companion DDM volumes. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.esd.maricopa.gov/DocumentCenter/View/2369/Drainage-Policies-and-Standards-Manual-for-Maricopa-County---revised-112025-PDF", "landing_page_url": "https://www.esd.maricopa.gov/", "retrieved_at": "2026-08-10T08:24:40.117Z", "original_filename": "maricopa-county-az.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 36, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:04:46.625Z", "enrich_model": "composer-2.5:run-608b9b73-87f4-47c6-9606-0ef8f91719c5", "enrich_notes": "First flush WQ volume is 0.5 in direct runoff (glossary; aligns with Policy 3.6.6 in atlas). Retention/storage reports must show basin draining within 36 h after the design precipitation event (6.14.3). Minimum design storm for new development retention is 100-year, 2-hour per Standard 6.10.2 (atlas); rainfall depth not in excerpts. Appendix E/F and Standards 6.10.x (drain time, permeability, drywells) referenced in revision history but numeric SCM criteria largely absent from provided pages.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "md-sha-drainage", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/md-sha-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/md-sha-drainage.json", "document_metadata": { "jurisdiction_name": "Maryland", "jurisdiction_level": "state", "state_code": "MD", "document_title": "MDOT SHA Drainage Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50 ], "water_quality_volume_method": "Water Quality Volume Maryland Department of Transportation Chapter 1: Introduction P a g e | 1-10 State Highway Administration September 2023 Table 1-3: Symbols SYMBOL DEFINITION UNITS A Area of cross section of flow ft2", "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "HEC-RAS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "MDOT SHA Drainage Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "ame 4% storm would be referred to as a “25-year storm”. With this nomenclature, the meaning is still the same: Maryland Departm", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": ".............................. 2-11 2.7 Rational Method ........................................................................", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume Maryland Department of Transportation Chapter 1: Introduction P a g e | 1-10 State Highway Administration September 2023 Table 1-3: Symbols SYMBOL DEFINITION UNITS A Area of cross section of flow ft2", "page_or_section": null }, { "field": "practice_mentions.swale", "excerpt": "Roadside, Median, and Interceptor ditches or swales 10-year 9 inches below edge of shoulder", "page_or_section": "Table 3-1, Section 3.4 (page 3-5)" }, { "field": "practice_mentions.swale", "excerpt": "Shallow Concentrated Flow is flow in swales, rills, and gullies that are assumed to not have a well-defined / regular channel shape.", "page_or_section": "Section 2.5.4 (page 2-9)" }, { "field": "practice_mentions.swale", "excerpt": "Grate Inlet. A drainage inlet composed of a grate in the roadway section or in the roadside swale or channel.", "page_or_section": "Section 5.1.4 Definitions (page 5-2)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MDOT SHA Drainage Manual Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://roads.maryland.gov/ohd2/MDOTSHADrainageManual.pdf", "landing_page_url": "https://roads.maryland.gov/", "retrieved_at": "2026-08-11T17:59:10.538Z", "original_filename": "md-sha-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T09:06:37.112Z", "enrich_model": "composer-2.5:run-8c319f30-bf33-41a1-b2e7-a9fbefafa335", "enrich_notes": "Excerpts are highway drainage (hydrology, channels, culverts, storm drains), not MD SWM BMP sizing. Stormwater Management is referenced externally (1.6). Roadside/median interceptor ditches or swales use 10-year design frequency with 9 in freeboard below shoulder (Table 3-1). Shallow concentrated flow in swales uses NEH velocities; no SCM drawdown, WQV depth, infiltration design rate, or BMP media depths in corpus.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "md-state", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/md-state/", "data_url": "https://stormwateratlas.com/data/manuals/md-state.json", "document_metadata": { "jurisdiction_name": "Maryland", "jurisdiction_level": "state", "state_code": "MD", "document_title": "Maryland Stormwater Design Manual", "version_or_edition": "Volume One", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "WQv is calculated as (P)(Rv)(A)/12, where P is the rainfall depth (1.0 inch in the Eastern Rainfall Zone, 0.9 inch in the Western Rainfall Zone), Rv is the volumetric runoff coefficient (0.05 + 0.009 * I), and A is the site area in acres.", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Systems", "Open Channel Practices", "Non-structural Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Maryland Stormwater Design Manual", "page_or_section": "TOC-1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "State of Maryland", "page_or_section": "TOC-3" }, { "field": "document_metadata.state_code", "excerpt": "State of Maryland", "page_or_section": "TOC-3" }, { "field": "document_metadata.document_title", "excerpt": "Maryland Stormwater Design Manual", "page_or_section": "TOC-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Rainfall Depths Associated with the 1,2,10 and 100-year, 24-hour Storm Events", "page_or_section": "2.11, Table 2.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv = (1.0) (Rv)(A) Eastern Rainfall Zone ... WQv = (0.9) (Rv)(A) Western Rainfall Zone ... where: WQv = water quality volume (in acre-feet) Rv = 0.05 + 0.009(I)", "page_or_section": "2.2, Section 2.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The models TR-55 and TR-20 (or approved equivalent) shall be used for determining peak discharge rates.", "page_or_section": "2.10, Section 2.3" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "TR-20 Technical Release No. 20 Project Formulation-Hydrology, computer program\nTR-55 Technical Release No. 55 Urban Unit Hydrology for Small Watersheds", "page_or_section": "1.21, Table 1.3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Acceptable BMP groups are:\n- Stormwater Ponds\n- Stormwater Wetlands\n- Infiltration Practices\n- Filtering Systems\n- Open Channel Practices\n- Non-structural Practices", "page_or_section": "1.16, Section 1.3.1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "ED 24 hour drawdown of the water quality volume", "page_or_section": "Table 1.3, Section 1.6 (page 36)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The water quality requirement can be met by providing a 24 hour drawdown of a portion of the water quality volume (WQv)", "page_or_section": "Chapter 2, Section 2.4 (page 42)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Cpv = 24 hour (12 hour in USE III and IV watersheds) extended detention of post-developed one-year, 24 hour storm event.", "page_or_section": "Table 2.1, Chapter 2 (page 39)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "filter bed inverts shall be separated at least four feet vertically (two feet on the lower Eastern shore) from the seasonal high water table.", "page_or_section": "Chapter 5, Micro-bioretention (page 245)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention systems (F-6) shall consist of the following treatment components: A 2½ to 4 foot deep planting soil bed", "page_or_section": "Chapter 3.4.5 Filtering (page 121)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 12\" deep surface ponding area.", "page_or_section": "Chapter 3.4.5 Filtering (page 121)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Flowpaths of 1.5:1 (length relative to width) and irregular shapes are recommended.", "page_or_section": "Section 3.1.4 Pond Treatment Criteria (page 92)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P= rainfall depth in inches and is equal to 1.0\" in the Eastern Rainfall Zone and 0.9\" in the Western Rainfall Zone", "page_or_section": "Table 2.1, Chapter 2 (page 39)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Adoption and revision dates are not explicitly stated as full ISO dates in the provided text, so they were left null. TR-55 outputs carry 1997 and 1998 system dates but do not explicitly represent the legal publication/revision dates of the manual itself. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://mde.maryland.gov/programs/water/StormwaterManagementProgram/Documents/www.mde.state.md.us/assets/document/sedimentstormwater/MD%20SWM%20Volume%201.pdf", "landing_page_url": "https://mde.maryland.gov/programs/water/stormwatermanagementprogram/pages/stormwater_design.aspx", "retrieved_at": "2026-08-07T10:44:00.000Z", "original_filename": "md-swm-volume-1.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:07:22.073Z", "enrich_model": "composer-2.5:run-378c926d-4065-4b00-a279-303cdf84a659", "enrich_notes": "WQv rainfall P is zone-specific (1.0 in Eastern Rainfall Zone, 0.9 in Western); no single wqv_depth_inches reported. SHWT separation also stated as 24 in (2 ft) on lower Eastern Shore for micro-bioretention and enhanced filters. Cpv extended detention is 12 h in USE III and IV watersheds vs 24 h elsewhere. F-6 filter drain times: 1.67 days (sand), 2.0 days (bioretention)—not converted to hours here. Infiltration BMPs (I-1, I-2) require WQv to infiltrate over a two-day period (48 h) but not mapped to max_drawdown_hours without inference.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ma-massdot-drainage", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/ma-massdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ma-massdot-drainage.json", "document_metadata": { "jurisdiction_name": "Massachusetts", "jurisdiction_level": "state", "state_code": "MA", "document_title": "MassDOT Stormwater Design Guide 2023 Edition", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 10, 25, 100 ], "water_quality_volume_method": "Water Quality Volume vii MassDOT Stormwater Design Guide | Preface Preface Purpose and Scope As presented herein by the Massachusetts Department of Transportation, Highway Division (MassDOT), the Stormwater Design Guide", "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)", "TR-20" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Infiltration Basin", "Filter Strip", "Permeable Pavement", "Oil/Grit Separator", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Massachusetts", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "MassDOT Stormwater Design Guide 2023 Edition", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "easures (SCMs) that, based on more than 25 years of experience, are supported and promoted by MassDOT to meet regulatory requir", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Pollutant Discharge Elimination System NRCS Natural Resources Conservation Service O&M Operation and Maintenance ORW Outsta", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume vii MassDOT Stormwater Design Guide | Preface Preface Purpose and Scope As presented herein by the Massachusetts Department of Transportation, Highway Division (MassDOT), the Stormwater Design Guide", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Infiltration Basin, Filter Strip, Permeable Pavement", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The designer should use a WQV equal to 1.0 inches times the IA of the post-development project site when a discharge is: • From LUHPPLs • In soils with Rapid Infiltration Rates (i.e., saturated hydraulic conductivity >2.4 in/hr)", "page_or_section": "Chapter 2, MassDOT Evaluation Method (page 42)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Designers should use the TSS reductions table found within the Massachusetts Stormwater Handbook to demonstrate 80% TSS reduction for a Water Quality Volume (WQV) equal to 0.5 inches times the Impervious Area (IA).", "page_or_section": "Chapter 2, MassDOT Evaluation Method (page 42)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All infiltration SCMs and pretreatment basins/sumps should dewater within 72 hours so that standing water doe", "page_or_section": "Section 4.8.2 Pretreatment and Design Criteria (page 137)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Groundwater levels for SCMs designed to be dry should allow the SCM to drain between storm events (typically a 72-hour drawdown period)", "page_or_section": "Section 3.3.3.2 Site Evaluation (page 86)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The design drawdown period should be 72 hours or less", "page_or_section": "Section 4.1.2 Sediment Forebay (page 96)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The SHWT is a minimum of two feet below the proposed bottom surface of the SCM", "page_or_section": "Section 4.8.1 Soils and Siting Criteria (page 137)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Vertical separation to SHWT should be a minimum of two feet above seasonal high groundwater and two to four feet above bedrock.", "page_or_section": "Table 4-2 Pavement Disconnection / QPA (page 100)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Unless upstream of a wet SCM, bottom of forebay should be a minimum of two feet above the seasonal high water table (SHWT)", "page_or_section": "Section 4.1.2 Sediment Forebay (page 96)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The infiltration rate of soils under the elevation of the SCM bottom is ≥ 0.17 inches per hour, or site-specific geotechnical investigations of this soil layer indicate the full storage volume will infiltrate within 72 hours", "page_or_section": "Section 4.8.1 Soils and Siting Criteria (page 137)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "An extended dry detention basin is a surface impoundment designed to detain the WQV and/or DSV for a duration of 24 to 72 hours.", "page_or_section": "Section 4.5.1 Extended Dry Detention Basin (page 121)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "WQV and/or DSV drawdown is 24 – 72 hours. Minimum 24 hours allows time for coarse and finer particulates to settle.", "page_or_section": "Section 4.5.1 Extended Dry Detention Basin (page 122)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Design characteristics common to all wetland types: • Length to width ratio: ≥ 2:1", "page_or_section": "Section 4.3.1 Constructed Stormwater Wetland (page 111)" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "The detention time should be between 12-24 hours and water levels should return gradually to normal within 24 hours of the rain event.", "page_or_section": "Section 4.3.1 Extended detention wetland description (page 111)" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Extended DetentionB Not Allowed 24 – 72 hoursC 24 – 72 hours 24 – 72 hoursC", "page_or_section": "Table 4-3 Constructed Stormwater Wetlands (page 113)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MassDOT Stormwater Design Guide 2023 Edition (ACEC-MA mirror; mass.gov download often 403 to bots)", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.acecma.org/wp-content/uploads/MassDOT_StormwaterDesignGuide_FINAL_508c.pdf", "landing_page_url": "https://www.mass.gov/info-details/stormwater-management-unit", "retrieved_at": "2026-08-11T17:59:10.573Z", "original_filename": "ma-massdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.17, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "permeable_pavement", "wet_pond" ], "enriched_at": "2026-08-13T09:01:43.160Z", "enrich_model": "composer-2.5:run-6dc9754e-c73a-4a02-b5dc-db6651d3e521", "enrich_notes": "MassDOT WQV depth is 0.5 in × IA for standard 80% TSS compliance; 1.0 in × IA is required for LUHPPLs, soils with saturated hydraulic conductivity >2.4 in/hr, Zone II/IWPA, and listed Critical Areas. Rapid infiltration threshold (>2.4 in/hr) triggers additional pretreatment but is not the design infiltration rate. Porous pavement reservoir course depth is sized to store WQV/ReV/DSV in void space (not a fixed inch depth); layer thicknesses include choker 4–8 in, filter 8–12+ in, filter blanket ≥3 in, total ≥65% of frost depth. Extended dry detention drawdown/detention is 24–72 h (minimum 24 h for brimful WQV/DSV). Extended detention wetland hydraulic detention is 12–24 h. CSW Table 4-3 assumes 1 in WQV depth for zone allocation (0.5 in case adjusts forebay WQV %). Sediment forebay sizing uses ≥0.1 in × contributing IA acreage.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ma-state-draft", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/ma-state-draft/", "data_url": "https://stormwateratlas.com/data/manuals/ma-state-draft.json", "document_metadata": { "jurisdiction_name": "Massachusetts", "jurisdiction_level": "state", "state_code": "MA", "document_title": "Massachusetts Stormwater Management Handbook", "version_or_edition": "Third Edition", "adoption_or_effective_date": null, "last_revised_date": "2023-12", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "calculated as the required runoff depth multiplied by the total post-construction impervious site area", "peak_flow_calculation_method": [ "NRCS Technical Release WinTR20 Project Formulation Method", "WinTR55 Small Watershed Hydrology Method" ], "required_hydrologic_hydraulic_software": [ "WinTR-20", "WinTR-55", "MODFLOW" ], "approved_bmp_categories": [ "Non-Structural", "Structural Pretreatment", "Structural Treatment", "Structural Conveyance", "Structural Infiltration", "Structural Other" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Massachusetts", "page_or_section": "Page i" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The Massachusetts Department of Environmental Protection (MassDEP) is responsible for implementing the Stormwater Management Standards under the Massachusetts Clean Waters Act", "page_or_section": "Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "Hardwick, MA", "page_or_section": "Page iv" }, { "field": "document_metadata.document_title", "excerpt": "Massachusetts Stormwater Handbook", "page_or_section": "Page i" }, { "field": "document_metadata.version_or_edition", "excerpt": "This is the third edition of the Massachusetts Stormwater Handbook.", "page_or_section": "Page ix" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Massachusetts Department of Environmental Protection (MassDEP) is responsible for implementing the Stormwater Management Standards under the Massachusetts Clean Waters Act, M.G.L. c. 21, §§ 26-53, and the Wetlands Protection Act, M.G.L. c. 131, § 40.", "page_or_section": "Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The post-development peak discharge rate must be designed to be equal to or less than the pre-development rate from the 2-year, 10-year, and 100-year 24-hour storms", "page_or_section": "Page 2-5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) is the runoff volume requiring treatment – it is calculated as the required runoff depth multiplied by the total post-construction impervious site area.", "page_or_section": "Page 2-14" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The peak discharge rate computations must be conducted using the NRCS Technical Release WinTR20 Project Formulation Method (Version 3.20 or later versions are permissible) or WinTR55 Small Watershed Hydrology Method (Version 1.00.10 or later versions are permissible).", "page_or_section": "Page 2-5" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "WinTR20 Project Formulation Method (Version 3.20 or later versions are permissible) or WinTR55 Small Watershed Hydrology Method (Version 1.00.10 or later versions are permissible).", "page_or_section": "Page 2-5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Non-Structural\nStreet Cleaning\nESSD Credits\nStructural Pretreatment\nDeep Sump Catch Basin\nOil/Grit Separator\nProprietary Separator\nSediment Forebay\nVegetated Filter Strip\nStructural Treatment\nBioretention Area\nConstructed Stormwater Wetland\nExtended Dry Detention Basin\nGravel Wetland\nProprietary Media Filter\nSand/Organic Filter\nTree Box Filter\nWet Basin\nRoof Dripline Filter\nStructural Conveyance\nDrainage Channel\nGrass Channel\nWater Quality Swale\nStructural Infiltration\nDry well\nInfiltration Basin\nInfiltration Trench\nLeaching Catch Basin\nPorous pavement\nSubsurface Infiltrator\nStructural Other\nDry Detention Basin\nGreen Roof\nRain Barrels & Cisterns", "page_or_section": "Page 2-18" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Required WQv is at least 1.0 inch times the total impervious area of the post-development site.", "page_or_section": "Table 2-4d / page 47 (Chapter 2)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Media Filters must be sized to treat the water quality volume (1.0 inch)", "page_or_section": "Appendix A Media Filters / page 341" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "conduct drawdown analysis to ensure the design volume from impervious area will infiltrate over 3-days based on Step 3 \"Drawdown within 72 Hours\".", "page_or_section": "Chapter 6 / page 187" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "It must be designed to fully dewater within 72-hours of a storm.", "page_or_section": "Appendix A Sediment Forebay / page 297" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "For design purposes, use 72 hours to evaluate dewatering, using the storm that produces 1.0 inch of runoff", "page_or_section": "Appendix A Media Filters / page 341" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Distance from bottom of SCM to SHGW 2-ft", "page_or_section": "Table 2.5 setback table / page 69" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Grass channels and dry water quality swales must be at least 2 feet above seasonal high groundwater.", "page_or_section": "Table 2-4d / page 47" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide minimum of two feet of separation between the bed bottom and the seasonal high groundwater elevation", "page_or_section": "Appendix A Porous Pavement / page 397" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The depth of the soil media must be between 2 to 4 feet.", "page_or_section": "Appendix A Bioretention / page 311" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the bioretention area must have a soil media with a depth of at least 30 inches to create anoxic conditions", "page_or_section": "Appendix A Bioretention / page 311" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum acceptable final soil infiltration rate is 0.01 inches per hour.", "page_or_section": "Appendix A Infiltration Basin / page 381" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Water levels in the extended detention wetlands may increase by as much as three feet after a storm, and return gradually to normal within 24 hours of the rain event.", "page_or_section": "Appendix A Extended Detention Wetlands / page 325" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "return gradually to normal within 24 hours of the rain event.", "page_or_section": "Appendix A Extended Detention Wetlands / page 325" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.ashlandmass.com/DocumentCenter/View/13272/MassDEP-Handbook_DRAFT-6_2023-12-14_withAppendices-2", "landing_page_url": "https://www.mass.gov/guides/massachusetts-stormwater-handbook-and-stormwater-standards", "retrieved_at": "2026-08-07T11:36:02.657Z", "original_filename": "ma-state-draft.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.01, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:02:21.677Z", "enrich_model": "composer-2.5:run-d3d5789b-35f3-4507-b440-bcd9c8fcf402", "enrich_notes": "WQv is 1.0 inch × post-development impervious area. Widespread 2-ft (24 in) separation from seasonal high groundwater for infiltration and many SCM bottoms. Infiltration drawdown and several dry SCMs require 72-hour dewatering. Bioretention soil media depth 2–4 ft (24 in minimum general; 30 in for nitrogen TMDL; 3 ft for trees/shrubs). Extended detention wetlands return to normal pool within 24 hours. Infiltration basin minimum acceptable soil infiltration rate 0.01 in/hr. Porous pavement: min 2-ft separation, slopes generally not >5%, subbase ≥40% voids (no storage depth in inches in excerpts).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nashville-tn-vol4", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nashville-tn-vol4/", "data_url": "https://stormwateratlas.com/data/manuals/nashville-tn-vol4.json", "document_metadata": { "jurisdiction_name": "Metropolitan Nashville and Davidson County", "jurisdiction_level": "municipality", "state_code": "TN", "document_title": "Stormwater Management Manual Volume 4 – Best Management Practices", "version_or_edition": "2021 (Section 1 Introduction only)", "adoption_or_effective_date": "2021", "last_revised_date": "2021", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Post-construction long-term BMP selection must meet Metro’s requirement of an 80% TSS reduction of an average annual urban pollutant load. Nonpoint-source pollution is most prevalent in runoff from small frequent storm events, typically less than 1.1 inches of rainfall; that fact was used in preparing selection, sizing, approach, and maintenance criteria in the BMP fact sheets. Stormwater quality management involves pollutant control, capture, and treatment for new development and redevelopment.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Temporary BMPs (construction EP&SC / good housekeeping)", "Permanent / post-construction treatment practices (PTP)", "Erosion Prevention and Sediment Control (EP&SC / PESC)", "Contractor activity BMPs (CP, TCP, ICP)", "Swales", "Sediment or detention ponds", "Pervious pavers / permeable concrete", "Grass-lined channels", "Infiltration BMPs", "Detention/retention facilities", "Vegetated swales/filters", "Source controls and perimeter/outfall controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Metropolitan Nashville - Davidson County Stormwater Management Manual Volume 4 – Best Management Practices", "page_or_section": "Section 1 cover, Page 1-1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "for each type of BMP to be used in the Metropolitan Nashville and Davidson County (Metro) area", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.state_code", "excerpt": "National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit issued by the Tennessee Department of Environment and Conservation (TDEC)", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Manual Volume 4 – Best Management Practices", "page_or_section": "Section 1 cover, Page 1-1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Volume 4 – Best Management Practices 2021", "page_or_section": "Section 1 cover, Page 1-1" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Volume 4 – Best Management Practices 2021... Any future release of this manual supersedes any and all previous manual releases. Each page is dated to indicate the release date.", "page_or_section": "Section 1.1, Pages 1-1 to 1-2" }, { "field": "document_metadata.last_revised_date", "excerpt": "Volume 4 – Best Management Practices 2021", "page_or_section": "Section 1 cover, Page 1-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "It was prompted by requirements in Metropolitan Nashville and Davidson County’s National Pollutant Discharge Elimination System (NPDES) Municipal Separate Storm Sewer System (MS4) permit issued by the Tennessee Department of Environment and Conservation (TDEC).", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Long-term BMP selection must be based upon the ability to meet Metro’s requirement of an 80% TSS reduction of an average annual urban pollutant load.", "page_or_section": "Section 1.6.1, Page 1-9" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Nonpoint source pollution is most prevalent in runoff from small frequent storm events. Typically these events are less than 1.1-inches of rainfall and that fact was used in preparing the selection, sizing, approach, and maintenance criteria presented in the BMP fact sheets.", "page_or_section": "Section 1.2, Page 1-2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Temporary BMPs are intended to address construction activities while permanent BMPs address long-term stormwater management objectives / requirements.... Permanent BMPs may include swales, sediment or detention ponds, and a variety of other features.", "page_or_section": "Section 1.5, Pages 1-7 to 1-8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Use pervious materials, such as pervious pavers or permeable concrete, where possible. Use grass-lined channels where site conditions allow.", "page_or_section": "Section 1.6.1, Page 1-9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Selecting BMPs for Contractor Activities (Sections CP, TCP and ICP)... Selection of Erosion Prevention and Sediment Control (EP&SC) Activities (Sections TCP and PESC)... Selection of Permanent Treatment Practices (Sections PESC and PTP)", "page_or_section": "Sections 1.6.3–1.6.5, Pages 1-11 to 1-16" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration BMPs may serve as groundwater recharge facilities, detention/retention areas may be created in landscaped areas of the project, and vegetated swales/filters may be used as roadside/median or parking lot median vegetated areas.", "page_or_section": "Section 1.6.5, Page 1-17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Typically these events are less than 1.1-inches of rainfall and that fact was used in preparing the selection, sizing, approach, and maintenance criteria presented in the BMP fact sheets.", "page_or_section": "Section 1.2, page 1-2" }, { "field": "practice_mentions.swale", "excerpt": "Permanent BMPs may include swales, sediment or detention ponds, and a variety of other features.", "page_or_section": "Section 1.5, page 1-7" }, { "field": "practice_mentions.swale", "excerpt": "Significant offsite flows (especially concentrated flows) that drain onto disturbed areas or slopes should be controlled through use of continuous berms, earth dikes, drainage swales, and lined ditches", "page_or_section": "Section 1.6.4.3, page 1-14" }, { "field": "practice_mentions.extended_detention", "excerpt": "Excavate permanent stormwater detention ponds early in the project, use them as sedimentation ponds during construction", "page_or_section": "Section 1.6.4.5, page 1-15" }, { "field": "practice_mentions.extended_detention", "excerpt": "Metro's detention policies address this issue for new development.", "page_or_section": "Section 1.3.1.2, page 1-4" } ], "extraction_quality": { "confidence": "low", "needs_human_review": true, "review_notes": "Source text is Volume 4 Section 1 introduction only (BMP selection overview). No numeric design-storm return periods, peak-flow calculation methods, or required software appear in this excerpt; hydrologic/design criteria live in other SWMM volumes/sections (e.g., Volumes 1–3 and BMP fact sheets). Re-extract when full Vol4 BMP fact sheets or Procedures/Theory volumes are available.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.nashville.gov/sites/default/files/2021-08/SWMM-Vol4-01_SECTION_1_0_ALL.pdf", "landing_page_url": "https://www.nashville.gov/departments/water/developers/stormwater-review/stormwater-management-manual/best-management-practices", "retrieved_at": "2026-08-08T10:35:25.202Z", "original_filename": "nashville-tn-vol4.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T09:19:41.594Z", "enrich_model": "composer-2.5:run-6a3d0271-7e5e-4275-bd28-0a57efe56b84", "enrich_notes": "Corpus is Volume 4 Section 1 (introduction and EP&SC overview) only. Text states small frequent storms are typically less than 1.1 inches of rainfall and that fact informed BMP fact sheet selection, sizing, and maintenance criteria, but no explicit WQv design depth or other SCM sizing numbers appear. Numeric design criteria are referenced as living in BMP fact sheets elsewhere in Vol. 4 and in Volumes 1–3.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mi-mdot-drainage", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/mi-mdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/mi-mdot-drainage.json", "document_metadata": { "jurisdiction_name": "Michigan", "jurisdiction_level": "state", "state_code": "MI", "document_title": "MDOT Drainage Manual Chapter 7", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "MDOT Drainage Manual Chapter 7", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "shall be based on a 10 percent chance (10-year) storm frequency. The sewer should be designed to flow full, i.e., with a hydra", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "oss traveled lanes. 7.3.7 Hydrology The Rational Method is the most common method in use for the design of storm sewers when a p", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "Reduction of peak flows can be achieved by the storage of runoff in detention basins, storm sewer pipes, swales or channels, and other detention storage facilities.", "page_or_section": "7.3.5 Detention Storage, page 11" }, { "field": "practice_mentions.swale", "excerpt": "It is preferable to slope median areas and inside shoulders to a center swale to prevent drainage from the median area from running across the pavement.", "page_or_section": "7.4.3.2 Roadside and Median Channels, page 15" }, { "field": "practice_mentions.swale", "excerpt": "Shallow swale sections at the edge of the roadway pavement or shoulder offer advantages over curbed sections where curbs are not needed for traffic control.", "page_or_section": "7.4.3.5 Curb and Gutter, page 16" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MDOT Drainage Manual Chapter 7 — Road Storm Drainage Systems Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.michigan.gov/mdot/-/media/Project/Websites/MDOT/Business/Design/Drainage-Manual/MDOT-MS4-Chap-07-Drainage-Manual.pdf", "landing_page_url": "https://www.michigan.gov/mdot/business/design/drainage-manual", "retrieved_at": "2026-08-11T17:59:10.586Z", "original_filename": "mi-mdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T09:09:35.041Z", "enrich_model": "composer-2.5:run-ade6fae7-a610-43a1-a515-ce371ff7f565", "enrich_notes": "Chapter 7 excerpt is road storm drainage (inlets, gutters, detention policy); SCM sizing criteria deferred to Chapter 8 Stormwater Storage Facilities. Detention storage and swales/channels named without numeric BMP design parameters in supplied pages.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "michigan-manual", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/michigan-manual/", "data_url": "https://stormwateratlas.com/data/manuals/michigan-manual.json", "document_metadata": { "jurisdiction_name": "Michigan", "jurisdiction_level": "state", "state_code": "MI", "document_title": "Michigan Nonpoint Source Best Management Practices Manual", "version_or_edition": "Rev 2017.6.27", "adoption_or_effective_date": "2017-06-27", "last_revised_date": "2017-06-27", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Treatment of runoff produced by all storm events up to and including the 10 percent exceedance runoff-generating storm event (first flush volume); statewide 10% exceedance precipitation values range from 0.77 to 1.00 inches. A conservative alternative is treatment of 1.0 inches of runoff over the entire site.", "peak_flow_calculation_method": [ "Presettlement hydrology unified sizing criteria", "NOAA Precipitation Frequency Data Server (PFDS)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Prevention/Minimization/Infiltration", "Treatment", "Mitigation", "Conveyance", "Storage", "Physical", "Vegetative", "Managerial", "Porous pavement", "Bio-retention cells", "Rain gardens", "Infiltration trench", "Infiltration basin", "Retention or detention basins", "Constructed wetlands" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Michigan Nonpoint Source Best Management Practices Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Michigan Department of Environmental Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Michigan Nonpoint Source Best Management Practices Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Michigan Nonpoint Source Best Management Practices Manual ('BMP Manual')", "page_or_section": "Page 3, Foreword" }, { "field": "document_metadata.version_or_edition", "excerpt": "Rev 2017.6.27", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Rev 2017.6.27", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "BMPs developed specifically for use in Michigan", "page_or_section": "Page 11" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "storms of 24-hour duration, with AEPs of 99.9%, 50%, 20%, 10%, 4%, 2%, and 1%; the corresponding average recurrence intervals of these AEPs are one (1), two (2), five (5), 10, 25, 50, and 100 years", "page_or_section": "Page 13, Hydrology" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treatment of runoff produced by all storm events up to and including the 10 percent exceedance runoff-generating storm event... A conservative alternative is treatment of 1.0 inches of runoff over the entire site.", "page_or_section": "Page 17, Unified Sizing Criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The recommended hydrologic baseline condition used in this manual is the presettlement hydrology of the site... Channel Protection – Maintain the calculated presettlement runoff volume and peak flow rate for all storm events up to the 2-year, 24-hour event.", "page_or_section": "Pages 13, 17" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "recommended that such values be obtained from a published, recognized source, such as the National Oceanic and Atmospheric Administration's (NOAA) Precipitation Frequency Data Server (PFDS)", "page_or_section": "Page 13, Hydrology" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "practices as either physical/vegetative, or managerial. Some BMPs may not include certain elements, either because the elements don’t apply, or because no reliable information exists for a given practice.", "page_or_section": "pp. 27–28" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "A conservative alternative is treatment of 1.0 inches of runoff over the entire site.", "page_or_section": "Page 17, Water Quality Volume" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treatment of runoff produced by all storm events up to and including the 10 percent exceedance runoff-generating storm event", "page_or_section": "Page 17, Water Quality Volume" }, { "field": "practice_mentions", "excerpt": "mitigation (by interception, detention, retention, treatment, and/or controlled release) of runoff from 90 percent of all runoff producing events", "page_or_section": "Page 17, 10 Percent Exceedance Precipitation Events" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "This PDF is Part 1 (introductory/background, 31 pages); individual BMP design specifications are published separately on the MDEQ BMP web page. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.last_revised_date", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.kalcounty.gov/DocumentCenter/View/2059/EGLE-Nonpoint-Source-Best-Management-Practices-Manual-PDF", "landing_page_url": "https://www.michigan.gov/egle/about/organization/water-resources/stormwater/municipal", "retrieved_at": "2026-08-08T00:55:00.000Z", "original_filename": "michigan-manual.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "wet_pond" ], "enriched_at": "2026-08-13T09:11:35.984Z", "enrich_model": "composer-2.5:run-fee8cab6-858b-4bfa-9fd3-77e8f4383cf1", "enrich_notes": "Document is Part 1 (introductory, 31 pages); individual BMP design specifications are published separately on the MDEQ BMP web page. Unified sizing uses five criteria (infiltration, water quality volume, channel protection, overbank flooding, extreme flooding). Primary WQv is runoff from storms through the 10% exceedance runoff-generating event; Figure 9 gage 10% exceedance precipitation depths range 0.77–1.00 inches. Channel protection targets presettlement volume/rate through the 2-year, 24-hour event; if full volume control is infeasible, capture and release the 1-year, 24-hour storm over 24 hours.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "kansas-city-marc-bmp", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/kansas-city-marc-bmp/", "data_url": "https://stormwateratlas.com/data/manuals/kansas-city-marc-bmp.json", "document_metadata": { "jurisdiction_name": "Mid-America Regional Council / Kansas City Metro APWA", "jurisdiction_level": "special_district", "state_code": "MO", "document_title": "Manual of Best Management Practices For Stormwater Quality", "version_or_edition": "Final, October 2012", "adoption_or_effective_date": "2012-10-01", "last_revised_date": null, "relationship_to_state_manual": "unknown" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Water Quality Volume (WQv) captures 90% of average annual runoff using the 1.37-inch Water Quality Storm for the Kansas City metropolitan area; WQv = P × Rv (Short-Cut Method) or P × weighted Rv (Small Storm Hydrology Method).", "peak_flow_calculation_method": [ "Rational Method", "SCS Curve Number Approach (TR-55)", "Short-Cut Method", "Small Storm Hydrology Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Stream Buffers", "Soil Preservation and Restoration", "Bioretention", "Rain Gardens", "Filtration Basins", "Infiltration Trenches", "Permeable Pavement", "Extended Detention Wetland", "Sand Filter", "Extended Wet Detention Basin", "Native Vegetation Swale", "Extended Dry Detention Basin", "Proprietary Media Filtration", "Hydro Dynamic Separation", "Catch Basin Inserts", "Baffle Boxes and Oil/Grit Separators", "Vegetated Filter Strip", "Green Roofs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The Kansas City Mid-America Regional Council (MARC) and the Kansas City Metro Chapter of the American Public Works Association (APWA) have developed this manual", "page_or_section": "Executive Summary" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Intended as a regional guidance document, this manual is a reference for BMP application and design.", "page_or_section": "Section 1.4" }, { "field": "document_metadata.state_code", "excerpt": "land development within the Kansas City Metropolitan Area and the MARC planning region", "page_or_section": "Executive Summary" }, { "field": "document_metadata.document_title", "excerpt": "Manual of Best Management Practices For Stormwater Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Final October 2012", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Final October 2012", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Detention basins detain and manage releases from larger rainfall events―usually up to and including the 100-year return interval event", "page_or_section": "Section 3.3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Water Quality Storm for the Kansas City Metropolitan Area is 1.37 inches", "page_or_section": "Section 6.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv = P * Rv", "page_or_section": "Section 6.2 Short-Cut Method" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "To size a conveyance BMP correctly, calculate the peak discharge for the Water Quality Storm using the Rational Method.", "page_or_section": "Section 6.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "weighted curve number (CN) for predevelopment conditions using Technical Reference No. 55 (TR-55)", "page_or_section": "Section 4.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "8.1 RAIN GARDENS ... 8.2 FILTRATION BASINS ... 8.3 INFILTRATION TRENCHES ... 8.4 BIORETENTION ... 8.5 PERMEABLE PAVEMENT ... 8.6 EXTENDED DETENTION WETLAND ... 8.7 SAND FILTER ... 8.8 EXTENDED WET DETENTION ... 8.9 NATIVE VEGETATION SWALE ... 8.10 EXTENDED DRY DETENTION BASIN", "page_or_section": "Table of Contents, Section 8" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5.1 STREAM BUFFERS ... 5.2 SOIL PRESERVATION AND RESTORATION ... 5.3 BIORETENTION", "page_or_section": "Table of Contents, Section 5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In the greater Kansas City Metropolitian area, the Water Quality Storm is the 1.37' rain event.", "page_or_section": "Section 3.3 / page 29" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Example: Design a rain garden to treat runoff from the water quality rainfall event for the Kansas City Metropolitan Area (1.37 inches)", "page_or_section": "Section 8.1.7 / page 110" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A cap with an orifice or an in-line orifice fitting shall be provided at or near the discharge point of the underdrain system to permit a 40-hr drawdown time for the WQv.", "page_or_section": "Section 8.4 / page 124" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Dry Detention Basin: Any detention facility, vegetated with native plants, designed to permit no permanent impoundment of water but designed to detain the water quality volume for forty (40) hours.", "page_or_section": "Section 2.0 Definitions / page 21" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "An extended detention wetland (EDW) is a constructed basin that has a permanent pool of water throughout the growing season and captures the water quality volume (WQv) and releases it over a 40-hour period.", "page_or_section": "Section 8.6.1 / page 147" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "verification that the location of bedrock and the seasonal high groundwater table are not closer than three feet from the sub-grade.", "page_or_section": "Section 8.5.5.1 / page 143" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "A minimum thickness of 12 inches should be used for the aggregate base.", "page_or_section": "Section 8.5.7.4 / page 145" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum infiltration/evaporation rate of 0.50 inches/day (~0.0208 inches/hour) should be used since testing showed an infiltration rate of 0.018 inch/hr", "page_or_section": "Section 8.5.10 / page 146" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "An EDW differs from an extended wet detention basin (EWDB) primarily in being shallower (approximately 18 inches maximum depth in an EDW main pool versus 6 to 12 feet maximum depth in a EWDB main pool).", "page_or_section": "Section 8.6.1 / page 147" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Regional MARC/APWA BMP manual for the Kansas City metropolitan area. Jurisdiction level coded as special_district because regional is not in schema. No required hydrologic software is mandated; computer software is optional for outlet sizing.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.marc.org/sites/default/files/2022-05/Best_Management_Practices_for_Stormwater_Quality.pdf", "landing_page_url": "https://www.marc.org/environment/environment-plans/stormwater-management", "retrieved_at": "2026-08-08T00:52:04.640Z", "original_filename": "kansas-city-marc-bmp.pdf" }, "design_parameters": { "wqv_depth_inches": 1.37, "max_drawdown_hours": 40, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": 0.0208, "permanent_pool_depth_inches": 18, "ed_drain_time_hours": 40, "length_to_width_ratio": null, "wetland_detention_hours": 40, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:45:07.238Z", "enrich_model": "composer-2.5:run-7752aaca-138c-4a06-b241-99db18675577", "enrich_notes": "WQv tied to 1.37-inch Water Quality Storm (90% annual runoff). Multiple detention BMPs require WQv release/drawdown over 40 hours; rain gardens should drain within 24–48 hours and max ponding 6 inches (Section 8.1). Permeable pavement: min 12-inch aggregate base, 3 ft SHWT separation, design drawdown uses 0.5 in/day (~0.0208 in/hr) when site rate is lower. EDW main pool max ~18 inches vs EWDB deeper pools (6–12 ft cited comparatively).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "milwaukee-wi", "processed_at": "2026-08-17T03:19:55.614Z", "detail_url": "https://stormwateratlas.com/milwaukee-wi/", "data_url": "https://stormwateratlas.com/data/manuals/milwaukee-wi.json", "document_metadata": { "jurisdiction_name": "Milwaukee Metropolitan Sewerage District", "jurisdiction_level": "special_district", "state_code": "WI", "document_title": "Chapter 13 Surface Water and Stormwater", "version_or_edition": "July 2020", "adoption_or_effective_date": null, "last_revised_date": "2020-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 100 ], "water_quality_volume_method": "Green infrastructure detention: 0.5 inch × net new impervious for sites 5,000 sf to ½ acre (MMSD Ch 13). Larger sites follow peak/volume match release criteria.", "peak_flow_calculation_method": [ "Allowable release: 100-year ≤ 0.5 cfs/acre; 2-year ≤ 0.15 cfs/acre", "Or volume matching alternative per Chapter 13" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Green infrastructure", "Detention", "Volume control practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Milwaukee Metropolitan Sewerage District", "page_or_section": "Chapter 13" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Metropolitan Sewerage District", "page_or_section": "Chapter 13" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 13 Surface Water and Stormwater", "page_or_section": "Title" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "unit that is violating this chapter. This action may include: stopping work on facilities under construction; stopping the design of facilities recommended by a facilities plan; deferring planning for sewerage system capacity expansion or relief; or placing a moratori", "page_or_section": "p. 5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "outflow during the 1% probability (100-year) storm that is no more than 0.5 cubic feet per second multiplied by the area of the site in acres and a post-development peak outflow during the 50% probability (2-year) storm event that is no more than 0.15 cubic feet per second m", "page_or_section": "p. 11" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "will add one-half acre or more of impervious surface, then a site development stormwater runoff management plan shall achieve either the allowable runoff release rate or the allowable runoff volume. (b) Requirement for redevelopment disturbing two acres or more If redevelop", "page_or_section": "p. 12" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "green infrastructure / detention", "page_or_section": "Chapter 13" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the development or redevelopment shall include green infrastructure with a detention volume equal to one-half inch multiplied by the area of the net new impervious surface", "page_or_section": "13.302(3)(c)1, page 12" }, { "field": "practice_mentions.bioretention", "excerpt": "Rain garden 4.4 gallons per square foot", "page_or_section": "13.303(4)(b) table, page 16" }, { "field": "practice_mentions.swale", "excerpt": "Bioswale 7.5 gallons per square foot", "page_or_section": "13.303(4)(b) table, page 16" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous pavement 3.0 gallons per square foot", "page_or_section": "13.303(4)(b) table, page 16" }, { "field": "practice_mentions.green_roof", "excerpt": "Green roof 1.0 gallon per square foot", "page_or_section": "13.303(4)(b) table, page 16" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Constructed wetlands 8.3 gallons per square foot", "page_or_section": "13.303(4)(b) table, page 16" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "MMSD Ch 13 Jul 2020 regional criteria covering Milwaukee metro. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method" ] }, "source": { "document_url": "https://www.mmsd.com/application/files/9515/9621/1174/Chapter_13_July_2020.pdf", "landing_page_url": "https://www.mmsd.com/", "retrieved_at": "2026-08-10T08:10:00.000Z", "original_filename": "milwaukee-wi.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:11:46.745Z", "enrich_model": "composer-2.5:run-3072f7a1-9fa7-4f79-b8e8-7a1b9327b002", "enrich_notes": "MMSD Ch 13 (Jul 2020): GI detention for 5,000 sf to ½ acre net new impervious is 0.5 in × net new impervious area (sec. 13.302(3)(c)). Detention credit table (13.303(4)(b)): Bioswale 7.5 gal/sf, Constructed wetlands 8.3, Green roof 1.0, Porous pavement 3.0, Rain garden 4.4 gal/sf. GI construction per WI DNR post-construction standards URL cited in sec. 13.303(4)(c). Larger sites (≥½ acre new impervious) use allowable release rate or volume match, not the 0.5 in GI rule.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mn-mndot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/mn-mndot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/mn-mndot-drainage.json", "document_metadata": { "jurisdiction_name": "Minnesota", "jurisdiction_level": "state", "state_code": "MN", "document_title": "MnDOT Drainage Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MnDOT Drainage Manual (2000) — complete published PDF Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.peak_flow_calculation_method", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name", "document_metadata.document_title" ] }, "source": { "document_url": "https://edocs-public.dot.state.mn.us/edocs_public/DMResultSet/download?docId=26996068", "landing_page_url": "https://www.dot.state.mn.us/bridge/hydraulics/drainage-manual-2000.html", "retrieved_at": "2026-08-11T17:59:10.554Z", "original_filename": "mn-mndot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T09:14:12.133Z", "enrich_model": "composer-2.5:run-e51a4e5d-dee3-4143-9e64-eb0c841f7bbe", "enrich_notes": "Corpus excerpt mn-mndot-drainage-c0001 (pages 1–190) contained no body text—only page markers—so no stormwater SCM design parameters could be extracted from the supplied source.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mn-state-2008", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/mn-state-2008/", "data_url": "https://stormwateratlas.com/data/manuals/mn-state-2008.json", "document_metadata": { "jurisdiction_name": "Minnesota", "jurisdiction_level": "state", "state_code": "MN", "document_title": "Minnesota Stormwater Manual", "version_or_edition": "Version 2, January 2008", "adoption_or_effective_date": "2008-01-01", "last_revised_date": "2008-01-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Unified sizing water quality volume (Vwq) based on rainfall depth representing 90% of annual runoff-producing events statewide (1.09 inches ± 0.04 inches) or 95% (1.46 inches ± 0.08 inches), with separate snowmelt Vwq computed for cold-climate sites and BMPs sized for the larger of rainfall or snowmelt volumes; framework also includes recharge (Vre), channel protection (Vcp), 10-year overbank flood (Vp10), and 100-year extreme flood (Vp100) criteria.", "peak_flow_calculation_method": [ "Rational Method", "NRCS Technical Release 55 (TR-55)", "NRCS Technical Release 20 (TR-20)", "SCS Type II 24-hour rainfall distribution" ], "required_hydrologic_hydraulic_software": [ "TR-55", "TR-20", "HEC-1", "HEC-HMS", "WinTR-55", "HEC-RAS" ], "approved_bmp_categories": [ "Pollution Prevention", "Better Site Design / Low Impact Development", "Runoff Volume Minimization", "Bioretention Practices", "Filtration Practices", "Infiltration Practices", "Stormwater Ponds", "Stormwater Wetlands", "Temporary Construction Erosion and Sediment Control", "Supplemental Pre- and Post-Treatment BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Minnesota Stormwater Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Published by the Minnesota Pollution Control Agency", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "St. Paul, MN 55155-4194", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Minnesota Stormwater Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Version 2. January 2008", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Version 2. January 2008", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Version 2. January 2008", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Created by the Minnesota Stormwater Steering Committee", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-Year design storm; 2-Year design storm; 5-Year design storm; 10-Year design storm; 25-Year design storm; 100-Year design storm", "page_or_section": "Chapter 8, Section 3.1.1 Precipitation" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The rainfall depth which represents 90% and 95% of runoff producing events was 1.09 inches (+/- 0.04 inches) and 1.46 inches (+/- 0.08 inches), respectively.", "page_or_section": "Chapter 8, Section 3.2.2 Water Quality Event" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "designers must make two water quality volume computations: snowmelt and rainfall runoff. The BMP would then be sized for the larger of the two results.", "page_or_section": "Chapter 8, Section 3.2.2 Water Quality Event" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Unified Stormwater Sizing Criteria ... Recharge and Infiltration Criterion (Vre) ... Water Quality Criteria ... Channel Protection Criteria (Vcp) ... Overbank Flood Protection Criteria (Vp10) ... Extreme Flood Control Criteria (Vp100)", "page_or_section": "Chapter 10 Table of Contents" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Rational Method is used to estimate peak runoff rates for very small sites. The simple equation for peak discharge is Q=CiA.", "page_or_section": "Chapter 8, Section 3.2.4 Runoff Coefficient" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Curve number tables are published in TR-55: Urban Hydrology for Small Watersheds", "page_or_section": "Chapter 8, Section 3.2.5 Curve Numbers" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The standard rainfall distribution used for urban areas in Minnesota for sizing and evaluation of BMPs (Chapter 10) is the Natural Resource Conservation Service's (NRCS) recommended SCS Type II rainfall distribution for urban areas.", "page_or_section": "Chapter 8, Section 3.2.1 Rainfall Distribution" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "TR-55 (original or DOS) ... HEC-1 ... HEC-HMS ... WinTR-20 (or TR-20) ... WinTR-55 ... HEC-RAS", "page_or_section": "Chapter 8, Table 8.1 Modeling Tool Selection" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Pollution Prevention: Chapter 12-1 ... Better Site Design: Chapter 12-2 ... Bioretention Practices: Chapter 12-6 ... Filtration Practices: Chapter 12-7 ... Infiltration Practices: Chapter 12-8 ... Stormwater Ponds: Chapter 12-9 ... Stormwater Wetlands: Chapter 12-10", "page_or_section": "Chapter 12 Table of Contents" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "(48 hours is the REQUIRED maximum tf for bioretention under the CGP)", "page_or_section": "Chapter 12-6 bioretention, page 397" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "the CGP requires that the water quality volume (see Chapter 10) be drawn down within 48 hours", "page_or_section": "Chapter 12 bioretention infiltration/recharge, page 375" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "requires a minimum distance of three feet between the bottom of an infiltrating BMP and the seasonally saturated water table", "page_or_section": "Chapter 7, page 174" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum of 3 feet of separation between the bottom of the bioretention practice and seasonally saturated soils (or from bedrock) is REQUIRED", "page_or_section": "Chapter 12-6 bioretention, page 397" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Facility filter media depth must be at least 2.5 feet deep", "page_or_section": "Chapter 12 bioretention, page 375" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "the recommended depth of the prepared soil is 30 inches", "page_or_section": "Chapter 12-6 bioretention, page 388" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "It is REQUIRED that permanent pool depths be a minimum of three feet and maximum of 10 feet at the deepest points", "page_or_section": "Chapter 12-9 stormwater ponds, page 470" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "It is HIGHLY RECOMMENDED that the Vcp be released over a minimum 24 hour period", "page_or_section": "Chapter 12-9 stormwater ponds, page 470" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Vwq equals 0.5 or 1.0 inch of runoff per impervious acre, depending on the receiving stream designation", "page_or_section": "Chapter 12-9 stormwater ponds, page 470" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Preferably, facilities of this type should have infiltration rates of 1\"/hr or greater", "page_or_section": "Chapter 12 bioretention infiltration/recharge, page 375" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Native soils with f>=0.2 in/hr", "page_or_section": "Table 7.8, page 182" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://stormwater.pca.state.mn.us/sites/stormwater/files/Minnesota_Stormwater_Manual.pdf", "landing_page_url": "https://stormwater.pca.state.mn.us/the_minnesota_stormwater_manual_1st_and_2nd_versions", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "mn-state-2008.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:14:55.464Z", "enrich_model": "composer-2.5:run-1f7202e9-db1f-4fe2-92e6-f0495c84b21a", "enrich_notes": "WQv runoff depth is stated as 0.5 or 1.0 inch per impervious acre (pond sizing) and 0.2 watershed-inch minimum for non-pond pre-treatment—no single canonical wqv_depth_inches. Design infiltration appears as ≥0.2 in/hr (infiltration trench soils, Table 7.8) and preferably ≥1 in/hr (infiltration/recharge bioretention)—not unified to one field value. Permanent pool depth field uses REQUIRED minimum 3 ft at deepest points; max 10 ft (8 ft recommended for phosphorus). max_drawdown_hours reflects CGP/required 48 hr WQ drawdown for bioretention and infiltration/recharge facilities.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ms-state-vol2", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ms-state-vol2/", "data_url": "https://stormwateratlas.com/data/manuals/ms-state-vol2.json", "document_metadata": { "jurisdiction_name": "Mississippi", "jurisdiction_level": "state", "state_code": "MS", "document_title": "Erosion Control, Sediment Control and Stormwater Management on Construction Sites and Urban Areas — Volume 2 Stormwater Runoff Management Manual", "version_or_edition": "Published 2011", "adoption_or_effective_date": "2011", "last_revised_date": "2011", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50 ], "water_quality_volume_method": "Capture and treat a water quality volume typically equal to the first 1 inch or first 1.5 inches of rainfall, sized with Schueler's Simple Method (Appendix A). Recommended BMP-specific treatment volumes include: wet detention — first 0.5 inch of runoff or 1.5 inches from impervious area; dry retention and constructed wetlands — first 1.0 inch of runoff or 2.5 inches from impervious area (whichever is greater for dry retention).", "peak_flow_calculation_method": [ "SCS Runoff Curve Number Method", "Short Cut Floodrouting Method (detention storage within method limits)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Planning (Conservation Easements, Open Space Design, Protection of Natural Features, Street Design, Urban Forestry, Redevelopment)", "Site Design (Alternative Turnarounds, Eliminating Curbs and Gutters, Green Parking, Green Roofs, Narrower Residential Streets, Riparian/Forested Buffer)", "Infiltration (Grassed Swales, Infiltration Basin, Infiltration Trench, Permeable Interlocking Concrete Pavement, Pervious Asphalt, Pervious Concrete)", "Filtration (Bioretention/Rain Gardens, Catch Basin Inserts, Sand and Organic Filters, Vegetated Filter Strip)", "Retention/Detention (Constructed Stormwater Wetland, Dry Detention Ponds, In-line Storage, Wet Pond)", "Manufactured Stormwater Treatment Systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Mississippi Department of Environmental Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Volume 2 Stormwater Runoff Management Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Jackson, Mississippi", "page_or_section": "Acknowledgments / Steering Committee" }, { "field": "document_metadata.document_title", "excerpt": "Erosion Control, Sediment Control and Stormwater Management on Construction Sites and Urban Areas Handbook for Volume 2 Stormwater Management... Volume 2 Stormwater Runoff Management Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "standards. In response, ITE has published “Traditional Neighborhood Development Street Design Guidelines” (1999) and “Neighborhood Street Design Guidelines” (2003). Public officials may also use the Better Site Design handbook (CWP, 1998) to conduct a review of their own", "page_or_section": "p. 59" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "standards. In response, ITE has published “Traditional Neighborhood Development Street Design Guidelines” (1999) and “Neighborhood Street Design Guidelines” (2003). Public officials may also use the Better Site Design handbook (CWP, 1998) to conduct a review of their own", "page_or_section": "p. 59" }, { "field": "document_metadata.last_revised_date", "excerpt": "standards. In response, ITE has published “Traditional Neighborhood Development Street Design Guidelines” (1999) and “Neighborhood Street Design Guidelines” (2003). Public officials may also use the Better Site Design handbook (CWP, 1998) to conduct a review of their own", "page_or_section": "p. 59" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Volume 2 – Stormwater Runoff Management Manual was created by adapting North Carolina's Stormwater Best Management Practices Manual (2007) with Mississippi-specific information where appropriate.", "page_or_section": "Acknowledgments" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the post-construction peak stormwater discharge rate must be reduced to no greater than the pre-construction peak stormwater discharge rate (usually for the 2-year, 24-hour storm).", "page_or_section": "Chapter 1, Comparison of BMP Treatment Capabilities" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "grass swales are designed with a capacity to handle the peak flow rate from a 10-year storm, and fall below erosive velocities for a 2-year storm.", "page_or_section": "Chapter 4, Grassed Swales" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Designed for an extended detention time of 24 hours for the 1-year storm event.", "page_or_section": "Additional Criteria, Constructed Wetland Systems" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Detention basins and associated outflow structures should be designed to address the 2-year, 5-year, 10-year, 25-year, and 50-year, 24-hour storm events.", "page_or_section": "Additional Criteria, Detention Practice Criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "There will be a volume of stormwater that must be captured and treated prior to release (typically first 1 inch or first 1.5 inches of rainfall).", "page_or_section": "Chapter 1, Comparison of BMP Treatment Capabilities" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Compute the water quality volume (WQV) using Schueler's Simple Method, as described in Chapter 3 and summarized below", "page_or_section": "Chapter 4, Sand and Organic Filters" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Required volume: First 0.5 inch of runoff or 1.5 inches of runoff from impervious area.", "page_or_section": "Additional Criteria, Wet Detention Systems" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Required volume: first 1.0 inch of runoff or 2.5 inches from impervious areas, whichever is greater.", "page_or_section": "Additional Criteria, Dry Retention Systems" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Runoff volumes and rates may be calculated using the SCS Runoff Curve Number Method (see Appendix Volume, Appendix A, A-16).", "page_or_section": "Additional Criteria, Detention Practice Criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Detention storage may be determined using the Short Cut Floodrouting Method for determining drainage areas and runoffs that fall with the method's limits.", "page_or_section": "Additional Criteria, Detention Practice Criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Manufactured Stormwater Treatment Systems: These systems are recommended for use in commercial and industrial developments.", "page_or_section": "Additional Criteria" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Infiltration devices must be able to completely dewater within 5 days.", "page_or_section": "Chapter 4 Infiltration, page 106 (4-75)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "bioretention areas require a minimum depth to groundwater of 2 feet", "page_or_section": "Introduction, page 13 (1-8)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "provide significant separation distance (2 to 5 feet) from the bottom of the infiltration basin and the seasonally high groundwater table", "page_or_section": "Chapter 4 Infiltration Basin, page 106 (4-75)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the seasonal high water table must be at least 2 ft below the base of the permeable pavement or gravel storage layer", "page_or_section": "PICP Design Criteria, page 115 (4-84)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Basin floor should be at least three feet above the seasonal high groundwater table elevation", "page_or_section": "Additional Criteria Dry Retention, page 196 (4-165)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "underlying soils must have an infiltration rate of 0.52 inch per hour or greater", "page_or_section": "Infiltration Trench, page 110 (4-79)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Average flow path through the basin should have a length-to-width ratio of at least 3:1", "page_or_section": "Additional Criteria Dry Retention, page 196 (4-165)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Water must then drain to a level 24 inches below the surface of the cell within 48 hours (maximum)", "page_or_section": "Bioretention Drainage Considerations, page 138 (4-107)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If in situ soil permeability is less than 2 inches/hour, the bioretention facility will likely have an underdrain system", "page_or_section": "Bioretention Step 6, page 138 (4-107)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Volume 2 BMP design manual adapted from North Carolina 2007; Appendix A calculation details referenced but not fully present in this Volume 2 text extract. Treatment volumes vary by BMP type in Additional Criteria section. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.mdeq.ms.gov/wp-content/uploads/2017/05/Volume_2.pdf", "landing_page_url": "https://www.mdeq.ms.gov/water/surface-water/nonpoint-source-pollution-program/stormwater-runoff-management-manual/", "retrieved_at": "2026-08-08T10:20:00.000Z", "original_filename": "ms-state-vol2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 120, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.52, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:17:21.213Z", "enrich_model": "composer-2.5:run-90d89601-1a91-424c-99b8-8f9ee34cc584", "enrich_notes": "MS Vol. 2 (NC 2007 adaptation). Treatment volumes are BMP-specific in Additional Criteria (e.g., dry retention: first 1.0 in runoff or 2.5 in from impervious; wet detention per atlas context not fully in excerpt). SHWT separation often stated as 2–5 ft for infiltration; 2 ft minimum cited for bioretention GW; dry retention basin floor ≥3 ft above SHWT (36 in). Bioretention: max 12 h surface ponding; ponded volume must drain so water is 24 in below surface within 48 h max. Grassed channel WQ sizing uses ~10 min travel time (flow-based, not volume). PICP/pervious: SHWT ≥2 ft below storage/base; slopes >2% need extra design; long-term surface infiltration cited >1 in/hr when clogged. Infiltration soils must be ≥0.52 in/hr (field verified). Green roof: slopes >20° need support systems (degrees, not %).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "missouri-manual", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/missouri-manual/", "data_url": "https://stormwateratlas.com/data/manuals/missouri-manual.json", "document_metadata": { "jurisdiction_name": "Missouri", "jurisdiction_level": "state", "state_code": "MO", "document_title": "Missouri Guide to Green Infrastructure: Integrating Water Quality into Municipal Stormwater Management", "version_or_edition": "PUB2446, May 2012", "adoption_or_effective_date": "2012-05", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Guidance (not hard statewide sizing): most common option uses a water quality volume based on water quality rain events that occur roughly 90% of the time, with SCMs designed to infiltrate, evapotranspire, or reuse runoff to the MEP; literature cited for Missouri-scale rainfall notes 0.5–1.5 inch events produce up to ~90% of annual runoff volume and ~75% of pollutant mass, with a typical one-inch channel-forming event for energy controls. Alternative option uses site-specific continuous simulation to mimic pre-construction runoff conditions.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Ponds / Extended Wet Detention", "Rain Gardens", "Bioretention Areas", "Infiltration Trenches and Basins", "Dry Wells", "Green Roofs", "Cisterns / Storage Tanks (Rainwater Harvesting)", "Pervious Pavements", "Tree Boxes / Tree Vaults", "Bioswales (Vegetative Swales)", "Filter Strips", "Grass Swales", "Constructed Wetlands", "Dry Basins / Multi-Chamber Catch Basins", "Stream Buffers / Riparian Setbacks" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Missouri Guide to GREEN INFRASTRUCTURE Integrating Water Quality into Municipal Stormwater Management PUB2446, May 2012", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This guide is designed to be useful across Missouri where there is a wide range of runoff conditions, soils, quality of receiving water, development practices and community values.", "page_or_section": "Executive Summary" }, { "field": "document_metadata.state_code", "excerpt": "Missouri Department of Natural Resources", "page_or_section": "Acknowledgements" }, { "field": "document_metadata.document_title", "excerpt": "Missouri Guide to GREEN INFRASTRUCTURE Integrating Water Quality into Municipal Stormwater Management", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "PUB2446, May 2012", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Published May 2012", "page_or_section": "Preface / Disclaimer and Purpose" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This guide is not a technical design manual; instead, it describes the processes and tools a community can use to develop sustainable site designs... The contents of this guide should not be interpreted as representing federal, state or local regulation.", "page_or_section": "Preface / Disclaimer and Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "In the past, design criteria for a two year storm for channel protection was commonly used, however, now the recommended channel protection criteria is for the one year storm event. ... low impact development is capable of automatically controlling the 10 and 100-year storms through its primary strategy of restoring the built area's natural rainfall-runoff relationship.", "page_or_section": "Chapter 1, Pages 15–16" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The first, and most common option, uses a concept sometimes referred to as \"water quality volume.\" In this option, water quality rain events that occur roughly 90 percent of the time over a given period of record... stormwater control measures are designed, constructed and maintained to infiltrate, evapotranspire or reuse runoff to the maximum extent practical. ... Option two involves site-specific engineering analysis... Data can be applied in continuous simulation models", "page_or_section": "Chapter 4, Section 4.1, Pages 102–103" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Examples include grass swales, filter strips, constructed wetlands, rain gardens and other bioretention practices. ... wet ponds, dry basins, or multi-chamber catch basins ... infiltration basins, subsurface trenches and pervious pavements. Chapter 6 practices include Green Roofs, Cisterns/Storage Tanks, Rain Gardens, Infiltration Trenches, Dry wells, Pervious Pavements, Tree Box and Tree Vault, Bioretention, Bioswales (Vegetative Swales), Filter strips, Wet Ponds, Constructed Wetlands.", "page_or_section": "Chapter 3, Section 3.1; Chapter 6" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Dry Detention Basin: any detention facility, vegetated with native plants, designed to permit no permanent impoundment of water but designed to detain the water quality volume for 40 hours.", "page_or_section": "Appendix A | page 238" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Wet Detention Basin: any detention facility designed to include a permanent pool and designed to detain the water quality volume for 40 hours.", "page_or_section": "Appendix A | page 238" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Minimum average depths of 6 to 8 feet help provide long term storage capacity for sediment.", "page_or_section": "Chapter 6 | page 211" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Research in Milwaukee, WI (Pitt, 1999) demonstrates rains between 0.5 and 1.5 inches are responsible for about 75 percent of the runoff pollutant discharges", "page_or_section": "Chapter 5 | page 145" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Even for those compounds with low contamination potential from surface infiltration, the depth to the groundwater must be considered if it is shallow (1 m or less in a sandy soil).", "page_or_section": "Chapter 5 | page 149" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Depth of amended soils is critical where specific infiltration volumes are assumed as part of stormwater control measure performance.", "page_or_section": "Chapter 6 | page 161" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "PUB2446 is statewide GI/LID guidance for municipalities, not a conventional design manual with mandatory statewide sizing equations or required hydrologic methods/software. Return periods (1, 2, 10, 100) and the ~90% WQv / 0.5–1.5 inch small-storm framing are recommended or literature-cited guidance; local MSD checklist examples (e.g., 1-year 24-hour channel protection) appear only as case/reference material. SUSTAIN is mentioned as an optional planning tool, not a required model. No last-revised date beyond May 2012 publication.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dnr.mo.gov/sites/dnr/files/vfc/2023/05/main/pub2446-mo-guide-to-green-infrastructure_1.pdf", "landing_page_url": "https://dnr.mo.gov/document-search/missouri-guide-green-infrastructure-pub2446", "retrieved_at": "2026-08-10T07:09:00.000Z", "original_filename": "missouri-manual.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 40, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:13:56.493Z", "enrich_model": "composer-2.5:run-c3536682-e8e6-474e-a4ac-5c0fa0f21f82", "enrich_notes": "Missouri PUB2446 is GI guidance, not a sizing manual. Appendix A defines Extended Dry Detention and Extended Wet Detention basins as detaining the water quality volume for 40 hours. Page 145 cites literature that 0.5–1.5 inch rains drive most pollutant mass (not a mandated WQv depth). Wet pond siting cites minimum average depths of 6–8 ft (ambiguous for a single permanent_pool_depth_inches). Constructed wetland zones: open water >18 in, low marsh 6–18 in, high marsh up to 6 in. SHWT: infiltration may be inappropriate if groundwater shallow (1 m or less in sandy soil) per Table 5.4 footnote—not a design separation requirement in inches.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "billings-mt", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/billings-mt/", "data_url": "https://stormwateratlas.com/data/manuals/billings-mt.json", "document_metadata": { "jurisdiction_name": "Montana", "jurisdiction_level": "state", "state_code": "MT", "document_title": "Montana Post-Construction Storm Water BMP Design Guidance Manual", "version_or_edition": "First Edition, September 2017", "adoption_or_effective_date": "2017-09", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Post-Construction Performance Standard (MS4 General Permit Part II.A.5.b.iii): infiltrate, evapotranspire, and/or capture for reuse the runoff from the first 0.5 inches of rainfall from a 24-hour storm preceded by 48 hours of no measurable precipitation (Runoff Reduction Volume, RRV = P×Rv×A/12 with P = 0.5 in and Rv = 0.05 + 0.9(I)). Remainder of that volume not reduced onsite (Runoff Treatment Volume) must be treated with BMPs expected to remove 80% TSS, or managed/treated offsite in the same subwatershed under MS4 offsite criteria.", "peak_flow_calculation_method": [ "NRCS TR-55 Graphical Peak Discharge Method (adapted for Runoff Treatment Flow)", "NRCS Runoff Curve Number method (TR-55 Chapter 2)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration Basin", "Bioretention", "Permeable Pavement Systems", "Dispersion", "Biofiltration Swale", "Extended Detention Basin", "Wet Detention Basin", "Proprietary Treatment Devices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Montana Post-Construction Storm Water BMP Design Guidance Manual ... Produced for: Montana’s MS4 Municipalities", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "--- page 10 --- Montana Post-Construction Storm Water BMP Design Guidance Manual September 2017 Contents Appendices Appendix A. Glossary Appendix B. Additional Hydrology Information Appendix C. Evaluating Soil Infiltration Rates Appendix D. Soil Amendments", "page_or_section": "pp. 10–12" }, { "field": "document_metadata.state_code", "excerpt": "Montana’s General Permit for Storm Water Discharges Associated with Small Municipal Separate Storm Sewer Systems (MS4s): Permit Number MTR040000", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "document_metadata.document_title", "excerpt": "Montana Post-Construction Storm Water BMP Design Guidance Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "First Edition September 2017", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "September 2017", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual is a guidance document... With the exception of referenced permit language, this manual does not convey requirements for storm water management practices in the state of Montana. However, it is expected that municipalities or other governing entities may adopt this manual", "page_or_section": "Preface, Foreword" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Generally, a 10- or 25-year return design storm is used to size storm drainage infrastructure and a 100-year return design storm is used to address upstream and downstream flooding", "page_or_section": "Section 3.4 Flood Control, Page 3-4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "P2 = 2-year, 24-hour rainfall (in) (refer to local jurisdiction for rainfall depths)", "page_or_section": "Section 3.3, Equation 3-7, Page 3-3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "infiltrate, evapotranspire, and/or capture for reuse the post-construction runoff generated from the first 0.5 inches of rainfall from a 24-hour storm preceded by 48 hours of no measurable precipitation... remainder... remove 80 percent total suspended solids (TSS)", "page_or_section": "Section 1.3.1, Pages 1-2 to 1-3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "RRV= PRvA/12 ... P = Water quality rainfall depth (use 0.5 inches) Rv = Dimensionless runoff coefficient, Rv = 0.05 + 0.9(I)", "page_or_section": "Section 3.2.1, Equation 3-1, Page 3-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "This procedure relies on the volume of runoff computed using Equation 3-1 and uses an adaptation of the NRCS TR-55 Graphical Peak Discharge Method", "page_or_section": "Section 3.3, Page 3-2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Determine the NRCS Runoff Curve Number (CN) using Equation 3-3, which is derived from the CN method described in Chapter 2 of TR-55", "page_or_section": "Section 3.3 Step 1, Page 3-2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Basin ... Bioretention ... Permeable Pavement Systems ... Dispersion ... Biofiltration Swale ... Extended Detention Basin ... Wet Detention Basin ... Proprietary Treatment Devices", "page_or_section": "Contents, Chapter 5" }, { "field": "max_drawdown_hours", "excerpt": "The recommended maximum drawdown time for the design volume is 72 hours.", "page_or_section": "5.2 Infiltration Basin, page 50" }, { "field": "shwt_separation_inches", "excerpt": "A minimum vertical distance of 3 feet is recommended between the bottom of the infiltration basin and the seasonal high water table or bedrock layer", "page_or_section": "5.2 Infiltration Basin, page 51" }, { "field": "bioretention_media_depth_min_inches", "excerpt": "Soil media is typically composed of a mixture of sand and organic matter, and ranges in depth from 18 to 36 inches.", "page_or_section": "5.3 Bioretention, page 68" }, { "field": "permeable_pavement_storage_depth_inches", "excerpt": "A minimum depth of 6 inches is recommended; however, the depth of this layer will vary depending on the expected traffic loading", "page_or_section": "5.4 Permeable Pavement Systems – Open-Graded Subbase Reservoir, page 83" }, { "field": "ed_drain_time_hours", "excerpt": "An EDB has a minimum 48-hour drain time for the RTV, facilitating the removal of TSS", "page_or_section": "5.7 Extended Detention Basin, page 116" }, { "field": "ed_drain_time_hours", "excerpt": "A minimum 48-hour drain time for the RTV facilitates the removal of TSS.", "page_or_section": "5.8 Wet Detention Basin, page 128" }, { "field": "shwt_separation_inches", "excerpt": "a minimum vertical distance of 3 feet is recommended between the bottom of the facility and the seasonally high groundwater table or bedrock for full and partial infiltration sections", "page_or_section": "5.3 Bioretention Site Selection, page 61" }, { "field": "practice_mentions", "excerpt": "Section 5.2 – Infiltration Basin ... Section 5.9 – Proprietary Treatment Devices", "page_or_section": "Chapter 5 introduction, page 47" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Statewide MS4 post-construction guidance hosted by Billings for Montana’s MS4 municipalities (Billings, Bozeman, Butte, Great Falls, Helena, Kalispell, Missoula) with DEQ cooperation. 0.5-in RRV/80% TSS performance standard and TR-55 RTF method are explicit. Flood-control return periods are general (10/25/100) and deferred to local jurisdictions; no specific required software named.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://mt-billingspublicworks.civicplus.com/DocumentCenter/View/119/Montana-Post-Construction-Storm-Water-Best-Management-Practices-BMP-Design-Guidance-Manual-PDF", "landing_page_url": "https://www.billingsmt.gov/", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "billings-mt.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": 6, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:36:36.773Z", "enrich_model": "composer-2.5:run-0c0c710c-1125-4ba9-a6ee-9fff386f4d5e", "enrich_notes": "Montana MS4 manual (Billings-hosted) uses 0.5-in RRV per atlas/permits but that depth is not stated in these excerpts. Infiltration basin max drawdown 72 h; EDB and WDB RTV drain time 48 h. SHWT separation commonly 3 ft (36 in) for infiltration bioretention and PICP subbase; 1 ft with liner; biofiltration swale bottom 1 ft. Bioretention filter media 18–36 in deep; PICP open-graded subbase minimum 6 in. Biofiltration swale longitudinal slope must be less than 5%. Dispersion and proprietary devices are covered but not mapped to wetland/green roof/trench/sand filter.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mt-deq8", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/mt-deq8/", "data_url": "https://stormwateratlas.com/data/manuals/mt-deq8.json", "document_metadata": { "jurisdiction_name": "Montana", "jurisdiction_level": "state", "state_code": "MT", "document_title": "Circular DEQ-8: Montana Standards for Subdivision Storm Water Drainage", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024", "last_revised_date": "2024", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Initial Storm Water Facility must infiltrate, evapotranspire, and/or capture for reuse post-development runoff from the first 0.5 inches of rainfall on impervious areas (V = 0.5 × Aimp / 12). For Standard Plans, BMPs designed per the Montana Post-Construction Storm Water BMP Design Manual may satisfy this volume if they treat/remove 80% TSS. Simplified Plan retention may use 250 ft³ per 1,000 ft² impervious (min 750 ft³) or Appendix B for the 100-year storm.", "peak_flow_calculation_method": [ "Rational Method", "Modified Rational Method", "TR-55 / SCS Curve Number Method", "Storage-Indication Routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Initial Storm Water Facility", "Retention Facilities", "Detention Facilities", "Infiltration Facilities", "Pre-treatment Facilities", "Conveyance Structures (open channels, storm sewers, culverts)", "Infiltration basins", "Bioretention", "Biofiltration swales", "Extended detention basins", "Wet detention basins", "Proprietary treatment devices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "MONTANA STANDARDS FOR SUBDIVISION STORM WATER DRAINAGE", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "These standards, based on demonstrated technology, set forth the requirements for the design and preparation of plans and specifications of storm water drainage systems in subdivisions in the State of Montana.", "page_or_section": "Foreword, page 2" }, { "field": "document_metadata.state_code", "excerpt": "Montana Department of Environmental Quality (Department)", "page_or_section": "Section 1.1" }, { "field": "document_metadata.document_title", "excerpt": "CIRCULAR DEQ-8 MONTANA STANDARDS FOR SUBDIVISION STORM WATER DRAINAGE", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2024 Edition", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "These standards replace Department of Environmental Quality (DEQ) Circular DEQ-8, 2017 Edition.", "page_or_section": "Foreword, page 2" }, { "field": "document_metadata.last_revised_date", "excerpt": "2024 Edition", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The standards were developed by the Montana Department of Environmental Quality (Department) in compliance with Section 76-4-104, MCA, of the Sanitation in Subdivisions Act, and ARM 17.36.310.", "page_or_section": "Section 1.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Calculations showing peak flow, at the time of concentration from all offsite basins impacting the site for the following storm events: (1) a 2-year storm event; (2) a 10-year storm event; and (3) a 100-year storm event.", "page_or_section": "Section 2.2.2.G, page 11–12" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Standard Plans must demonstrate that the post-development runoff flowrate from the proposed subdivision will not exceed the pre-development runoff flowrate during the 2-year storm event... Standard plans must not allow inundation of buildings or drainfields during a 100-year storm event.", "page_or_section": "Section 3.3, page 15" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Storm drainage designs must include an Initial Storm Water Facility sized to infiltrate, evapotranspire, and/or capture for reuse the post-development runoff generated from the first 0.5 inches of rainfall on impervious areas.", "page_or_section": "Section 3.4, page 15" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The BMPs must be designed specifically for the treatment and removal of 80 percent total suspended solids (TSS) from storm water runoff.", "page_or_section": "Section 3.4, page 16" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Rational Method may be used for calculating peak flow rate and volume of storm water runoff for areas less than 200 acres.", "page_or_section": "Section 3.7.1, page 17" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Modified Rational Method uses the peak flow rate (Q) calculated using the Rational Method equation... Urban Hydrology for Small Watersheds TR-55 is based on the SCS Curve Number Method.", "page_or_section": "Sections 3.7.2–3.7.3, pages 18–21" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The BMPs may include infiltration basins, bioretention, biofiltration swales, extended detention basins, wet detention basins, and proprietary treatment devices.", "page_or_section": "Section 3.4, page 16" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5. RETENTION FACILITIES... 6. DETENTION FACILITIES... 7. INFILTRATION FACILITIES... 8. PRE-TREATMENT FACILITIES... 4. CONVEYANCE STRUCTURES", "page_or_section": "Table of Contents" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Retention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "5.1 GENERAL, page 29" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Detention facilities should be designed to infiltrate, evapotranspire, and/or capture for reuse storm water and to hold runoff no more than 72 hours.", "page_or_section": "6.1 GENERAL, page 31" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "D. Be sized to drain within 48 hours; and", "page_or_section": "7.2 DESIGNS, page 34" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "B. Be constructed such that the bottom of the facility is one foot above any limiting layer.", "page_or_section": "5.2 DESIGNS, page 29" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "For detention facilities that have a minimum one-foot separation from the bottom of the facility to the seasonally high groundwater or bedrock layer, the facility must be designed to:", "page_or_section": "6.2 DESIGN, page 31" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A. Be constructed two feet above a limiting layer;", "page_or_section": "7.2 DESIGNS, page 34" }, { "field": "practice_mentions", "excerpt": "The BMPs may include infiltration basins, bioretention, biofiltration swales, extended detention basins, wet detention basins, and proprietary treatment devices. Permeable pavement systems and dispersion BMPs are not allowed as the initial storm water facility.", "page_or_section": "Section 3 (Standard Plans BMPs), page 16" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The measured infiltration must be divided by a safety factor of 2.0 to arrive at the design infiltration rate.", "page_or_section": "APPENDIX A, page 39" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Applies to subdivisions subject to Sanitation in Subdivisions Act review (ARM 17.36.310), not a general MS4/post-construction manual for all development. Computer models may be used (Section 2.6) but no specific software is required. Exact calendar effective date beyond '2024 Edition' not stated in text.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://deq.mt.gov/files/Water/Forms/DEQ_8_2024_FINAL_2024_09_20.pdf", "landing_page_url": "https://deq.mt.gov/water", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "mt-deq8.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:18:03.944Z", "enrich_model": "composer-2.5:run-9b54fe8f-0d42-42a2-b1b9-fa4e909655ef", "enrich_notes": "Initial storm water volume sizing (e.g., 0.5 in on impervious) is referenced in atlas context but not in supplied DEQ-8 excerpts. Standard Plan BMPs must meet Montana Post-Construction Storm Water BMP Design Manual (Sept 2017) for 80% TSS; detailed BMP dimensions are not in these pages. Infiltration facilities require 24 in (2 ft) clearance above a limiting layer (7.2.A), stricter than the 12 in one-foot separation for retention/detention bottoms to limiting layer or seasonally high groundwater. Infiltration must drain within 48 hours (7.2.D). Design infiltration rate = measured rate ÷ 2.0 safety factor (Appendix A); Table 3 soil-texture rates are cited but not included in corpus. Detention max depth 4 ft where applicable; wet-detention detail deferred to external BMP manual when separation < 1 ft.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "mt-mdt-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/mt-mdt-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/mt-mdt-drainage.json", "document_metadata": { "jurisdiction_name": "Montana", "jurisdiction_level": "state", "state_code": "MT", "document_title": "MDT Hydraulics Manual Chapter 9", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "EPA SWMM" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "MDT Hydraulics Manual Chapter 9", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "ff. 2. Base Flood. Another term for the 100-year event. 3. Depression/Retention Storage. The natural depression within a watersh", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ydrologic method for the site (e.g. the rational method is intended for small urban basins). Hydrology 9-5 Hydraulics Manual Jul", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "For structures that are designed to control the volume of runoff (e.g., detention storage facilities) or where flood routing through culverts is used, the entire discharge hydrograph is of interest.", "page_or_section": "9.1.1 Definition / page 4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. MDT Hydraulics Manual Chapter 9 — Hydrology Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.mdt.mt.gov/other/webdata/external/hydraulics/manuals/Chapter-09-Hydrology.pdf", "landing_page_url": "https://mdt.mt.gov/publications/manuals.aspx", "retrieved_at": "2026-08-11T17:59:10.604Z", "original_filename": "mt-mdt-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention" ], "enriched_at": "2026-08-13T09:18:21.357Z", "enrich_model": "composer-2.5:run-337f62e1-a2f5-478e-8b36-b0b72ae2164d", "enrich_notes": "Provided corpus is MDT Hydraulics Manual Chapter 9 (Hydrology): flood-frequency selection, hydrologic method comparison, and rainfall-runoff loss models (NRCS CN, Horton, Green-Ampt). No water-quality volume (WQv) method or explicit SCM/BMP sizing criteria appear in these excerpts. NRCS initial abstraction values 0.2 and 0.05 are dimensionless loss parameters, not WQv depth in inches.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "anchorage-ak", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/anchorage-ak/", "data_url": "https://stormwateratlas.com/data/manuals/anchorage-ak.json", "document_metadata": { "jurisdiction_name": "Municipality of Anchorage", "jurisdiction_level": "municipality", "state_code": "AK", "document_title": "Anchorage Stormwater Manual Volume 1 – Management and Design Criteria (Design Criteria Manual Chapter 2 – Drainage)", "version_or_edition": "Version 1.0, DRAFT March 2015", "adoption_or_effective_date": null, "last_revised_date": "2015-03", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Treat runoff from the first 0.52 inches of rainfall from a 24-hour event preceded by 48 hours of no precipitation (90th-percentile water quality storm) using Green Infrastructure (retention, infiltration, bioretention, evaporation, rainfall harvesting, and/or combinations). Volume estimated by Direct Determination Method or SWMM. Extended detention (when GI not used for WQ): detain post-development excess over pre-development for the 1-year, 24-hour storm for 6 hours. Oil/grit separator annual goals include 80% reduction of inorganic sediment ≥100 μm when traditional treatment is used.", "peak_flow_calculation_method": [ "Rational Method", "NRCS (SCS) Peak Flow Method (Tabular Method) / TR-55", "NRCS (SCS) Tabular Hydrograph Method", "Direct Determination Method (water quality volume)", "USGS Regression Equations", "Unit Hydrographs", "Kinematic-Wave Method", "Non-Linear Reservoir Method", "SCS Type I, 24-hour rainfall distribution" ], "required_hydrologic_hydraulic_software": [ "SWMM (EPA)", "HEC-HMS", "HEC-RAS", "PondPack", "HY-8" ], "approved_bmp_categories": [ "Bioretention", "Soakaway Pits", "Infiltration Basins", "Infiltration Trenches", "Vegetative Swales", "Pervious Pavement", "Chamber Systems", "Wet Ponds", "Dry Ponds (enhanced)", "Sedimentation Basins", "Filter Strips", "Constructed Wetlands", "Canopy Cover/Vegetation Retention", "Landscaped Depressions", "Oil and Grit Separators (traditional treatment when GI infeasible)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "MUNICIPALITY OF ANCHORAGE PROJECT MANAGEMENT & ENGINEERING DEPARTMENT", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "MUNICIPALITY OF ANCHORAGE", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "State of Alaska 18 AAC 70 Water Quality Standards", "page_or_section": "Section 1.4.2" }, { "field": "document_metadata.document_title", "excerpt": "ANCHORAGE STORMWATER MANUAL Volume 1 Management and Design Criteria (Design Criteria Manual Chapter 2 – Drainage)", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Version 1.0 DRAFT March 2015", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "DRAFT March 2015", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Local and State Codes Related to Stormwater... Municipal Stormwater Policies", "page_or_section": "Sections 1.4–1.5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Table 4.2-1: MOA Design Storm Depths... 10-year, 24-hour... 100-year, 24-hour... Extended Detention 1-year, 24-hour... Peak Flow Control 2-year, 24-hour... 10-year, 24-hour... 100-year, 24-hour", "page_or_section": "Table 4.2-1, Page 4-4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "= Intensity (in/hr) D = Duration (hr) 100-Year: I=0.5484D-0.5283 50-Year: I=0.4976D-0.5257 25-Year: I=0.4465D-0.5226 10-Year: I=0.3814D-0.5174 5-Year: I=0.3308D-0.5120 2-Year: I=0.2590D-0.5010 1-Year: I=0.2155D-0.4911 100-Year IDF Curve 50-Year IDF Curve 25-Year IDF Curve 10-Ye", "page_or_section": "pp. 56–57" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Treatment must be provided for runoff generated from the first 0.52 inches of rainfall from a 24-hour rainfall event preceded by 48 hours of no precipitation.", "page_or_section": "Section 3.2.2.1, Page 3-4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Treatment 90th Percentile, 24-hour Green Infrastructure Water Quality Treatment 0.52 0.52", "page_or_section": "Table 4.2-1, Page 4-4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Extended detention requires that applicable projects detain post-development project runoff in excess of the pre-development project runoff for the 1‐year, 24‐hour storm for a period of 6 hours.", "page_or_section": "Section 3.2.2.2, Page 3-6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "An 80 percent reduction of inorganic sediment particles equal to or greater than 100 μm.", "page_or_section": "Section 6.6.16 Oil and Grit Separators, Page 6-130" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "4.5.2 Rational Method... 4.5.3 NRCS (SCS) Peak Flow Method (Tabular Method)... 4.5.4 USGS Regression Equations... 4.5.5 NRCS (SCS) Tabular Hydrograph Method", "page_or_section": "Table of Contents / Chapter 4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The direct determination method or runoff volumes generated by SWMM are the only methods accepted by the MOA for estimating the volume of runoff required for water quality treatment through Green Infrastructure.", "page_or_section": "Section 4.5.1, Page 4-16" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Design storms for MOA drainage applications are based on an SCS Type I, 24-hour rainfall distribution", "page_or_section": "Section 4.2.4, Page 4-5" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Criteria March 2015 vii LIST OF TABLES Table 2.1-1: Summary of Urban Stormwater Pollutants ............................................................ 2-7 Table 3.2-1: Summary of Stormwater Standards and Requirements.......................................... 3-3 Table 4.", "page_or_section": "p. 9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention • Soakaway Pits • Infiltration Basins • Infiltration Trenches • Vegetative Swales • Pervious Pavement • Chamber Systems • Wet Ponds • Dry Ponds (if they are enhanced) • Sedimentation Basins • Filter Strips • Constructed Wetlands • Canopy Cover/Vegetation Retention • Landscaped Depressions", "page_or_section": "Section 3.2.2.1, Page 3-4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "For cases where green infrastructure is determined to be infeasible, water quality treatment may be achieved through traditional gray infrastructure such an oil and grit separator.", "page_or_section": "Section 3.2.2.1, Page 3-5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Treatment must be provided for runoff generated from the first 0.52 inches of rainfall from a 24-hour rainfall event preceded by 48 hours of no precipitation.", "page_or_section": "Section 3.2.2.1 Requirement 1 – Water Quality Treatment (page 44)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "In order for the soil to provide adequate treatment, the minimum depth of engineered soils is 3.0 feet.", "page_or_section": "Section 6.6 Bioretention Facilities – Engineered Soil (page 125)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "If the facility is constructed with under this modification, the growing media depth can be reduced to 18 inches", "page_or_section": "Section 6.6 Design Modification 2 – Impermeable Liner and Subdrain (page 129)" }, { "field": "practice_mentions.bioretention", "excerpt": "Allowable Green Infrastructure techniques are presented in Chapter 6 and include methods such as retention, infiltration, bioretention, evaporation, rainfall harvesting", "page_or_section": "Section 3.2.2.1 (page 44)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Separation from Groundwater5 (feet) ... Soakaway Pits ... 2 ... Infiltration Basins ... 2 ... Bioretention Facilities ... 26", "page_or_section": "Table 6.4-1 Stormwater Controls Selection Guide (page 115)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bioretention facility floor is less than 2 feet from the seasonally high groundwater table.", "page_or_section": "Section 6.6 Design Modification 2 (page 129)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "For these cases, the depth to the seasonally high groundwater table should be a minimum of 4-feet from the facility floor", "page_or_section": "Section 6.6 Wet Ponds (page 177)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Source PDF is labeled DRAFT March 2015 (ASM Volume 1 / DCM Ch. 2). Confirm whether a later adopted edition supersedes this draft before relying on criteria operationally. Software listed are common models in Table 4.8-1, not an exclusive required list.", "fields_not_found": [ "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.muni.org/departments/project_management/documents/2015%20draft%20asm%20volume%201%20-%20chapter%202%20dcm.pdf", "landing_page_url": "https://www.muni.org/Departments/project_management/", "retrieved_at": "2026-08-08T11:41:43.812Z", "original_filename": "anchorage-ak.pdf" }, "design_parameters": { "wqv_depth_inches": 0.52, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 36, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:25:22.299Z", "enrich_model": "composer-2.5:run-c6e51c18-e169-4b74-aa52-100a6246cf77", "enrich_notes": "WQv is the first 0.52 in of a 24-hr storm after 48 hr dry period (Section 3.2.2.1). Standard bioretention engineered soil minimum is 3.0 ft (36 in); lined Modification 2 allows 18 in growing media. Table 6.4-1 lists groundwater separation in feet (often 2 ft for infiltration-type controls; bioretention row shows 26 ft in the excerpt—verify in source PDF). Wet pond hotspot cases cite 4 ft minimum from seasonally high groundwater to facility floor. Subdrain Modification 1 triggered when groundwater/bedrock within 4 ft of facility floor. No explicit numeric ponding depth, ED drain time, or MTD verification program in supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ne-ndot-stf", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ne-ndot-stf/", "data_url": "https://stormwateratlas.com/data/manuals/ne-ndot-stf.json", "document_metadata": { "jurisdiction_name": "Nebraska Department of Transportation (NDOT)", "jurisdiction_level": "state", "state_code": "NE", "document_title": "Drainage Design and Erosion Control Manual, Chapter Three: Stormwater Treatment", "version_or_edition": "April 2018 (dated April 20, 2018); replaces September 2013 chapter", "adoption_or_effective_date": "2018-04-20", "last_revised_date": "2018-04-20", "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "WQV is the first 1/2 inch of runoff from the Treatment Drainage Area (new pavement), WQV = 0.5 in × area (ft²) / 12. Target is ≥80% average annual TSS load reduction. Alternatively size to the WQV Discharge Rate: peak from a 0.75-inch, 24-hour rainfall using the NRCS Curve Number procedure (CN=98 pavement, Tc=5 min; Weighted Q preferred for mixed cover).", "peak_flow_calculation_method": [ "NRCS Curve Number (CN) procedure", "Weighted Q method of the CN procedure" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Filter Strips", "Grass Swales", "Infiltration Trench", "Infiltration Basin", "Bioretention", "Media Filter", "Extended Dry Detention", "Wet Detention Pond", "Stormwater Wetland", "Pervious Pavement", "Proprietary Structural Treatment Control", "Other Reasonable Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "This Chapter provides designers with the necessary guidance for incorporating Water Quality Stormwater Treatment Facilities (STF) into Nebraska Department of Transportation (NDOT)", "page_or_section": "Page 3-1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The NDOT is a regulated MS4 and is required to meet the conditions of its National Pollutant Discharge Elimination System (NPDES) MS4 permit.", "page_or_section": "Page 3-4, Section 2.A" }, { "field": "document_metadata.state_code", "excerpt": "Nebraska Department of Transportation (NDOT)", "page_or_section": "Page 3-1" }, { "field": "document_metadata.document_title", "excerpt": "NDOT – Drainage Design and Erosion Control Manual April 2018 Chapter Three: Stormwater Treatment", "page_or_section": "Page 3-1" }, { "field": "document_metadata.version_or_edition", "excerpt": "The information contained in Chapter Three: Stormwater Treatment, dated April 20, 2018... This chapter replaces Chapter Three: Stormwater Treatment, dated September 2013.", "page_or_section": "Page 3-1" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Chapter Three: Stormwater Treatment, dated April 20, 2018... The Nebraska Division of the FHWA approved this chapter for use on the National Highway System", "page_or_section": "Page 3-1" }, { "field": "document_metadata.last_revised_date", "excerpt": "Chapter Three: Stormwater Treatment, dated April 20, 2018", "page_or_section": "Page 3-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The NDOT's stormwater treatment program does not supersede a LPA's stormwater treatment program or act as a minimum standard, except when a LPA project is being constructed", "page_or_section": "Page 3-4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Chapter One is used to define and direct the peak discharges of stormwater runoff during the highway Design Storms (2-year to 100-year storm events).", "page_or_section": "Page 3-26, Section 7.A.7" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "A wet detention pond can be used to reduce the post-development discharge to that of the pre-development rate under the 2-year, 10-year and 100-year event storms", "page_or_section": "Page 3-33, Section 7.C.8" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The NDOT has determined that the WQV is the first one-half (½) inch of runoff from the Treatment Drainage Area... WQV = 0.5 inch x Treatment Drainage Area (ft2) /12", "page_or_section": "Page 3-17, Section 6.A" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "This document recommends reducing the post development loadings of Total Suspended Solids (TSS) by a minimum of 80% of the average annual TSS loadings.", "page_or_section": "Page 3-17, Section 6.A.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The WQV Discharge Rate is the peak stormwater discharge generated by the water quality volume rainfall event using the Natural Resources Conservation Service (NRCS) Curve Number (CN) procedure. The water quality volume rainfall event is the 0.75 inch, 24-hour rainfall, assuming a CN value of 98 (pavement) and a Time of Concentration (Tc) of 5 minutes.", "page_or_section": "Page 3-18, Section 6.B" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "To determine a WQV peak discharge for drainage areas greater than 5 acres, the NRCS CN procedure must be used. The designer can either assume the entire area is pavement with a CN value of 98 or use the weighted Q method of the CN procedure.", "page_or_section": "Page 3-18, Section 6.B" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Storage practices such as extended-detention ponds... Filtration practices such as filter strips... Grassed swales... Bio-retention... Sand filters and... Infiltration practices such as infiltration basins and infiltration trenches", "page_or_section": "Page 3-3, Section 1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "7.C.1 Vegetated Filter Strips... 7.C.2 Grass Swales... 7.C.3 Infiltration Trench... 7.C.4 Infiltration Basin... 7.C.5 Bioretention... 7.C.6 Media Filter... 7.C.7 Extended Dry Detention... 7.C.8 Wet Detention Pond... 7.C.9 Stormwater Wetland", "page_or_section": "Pages 3-29 to 3-34, Section 7.C" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "7.C.10 Pervious Pavement... 7.C.11 Proprietary Structural Treatment Control... 7.C.12 Other Reasonable Practices", "page_or_section": "Section 7.C" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The NDOT has determined that the WQV is the first one-half (½) inch of runoff from the Treatment Drainage Area", "page_or_section": "Chapter Three, Section 6.A, Page 3-17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQV = 0.5 inch x Treatment Drainage Area (ft2) /12", "page_or_section": "Chapter Three, Section 6.A, Page 3-17" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "constricted by an outlet structure to produce low flow rates calculated to delay the drawdown of the basin over a 24 to 48 hour (72 hour maximum) period", "page_or_section": "Chapter Three, Section 7.C.7 Extended Dry Detention, Page 3-32" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Similarly, detention basins designed to detain runoff for less than 72 hours", "page_or_section": "Chapter Three, Section 2.C.1, Page 3-5" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Recommended in soils with a minimum infiltration rate of 0.5 in/h", "page_or_section": "Chapter Three, Section 7.C.3 Infiltration Trench, Page 3-30" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Recommended in soils with a minimum infiltration rate of 0.5 in/h.", "page_or_section": "Chapter Three, Section 7.C.4 Infiltration Basin, Page 3-31" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Extraction limited to Chapter 3 (Stormwater Treatment). Highway design-storm hydrology is referenced to Chapter One (2- to 100-year); only 2/10/100 are named explicitly in Ch3 (wet detention). No required modeling software named in this chapter.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dot.nebraska.gov/media/fhpdgmi4/f-chapter-3-stormwater-treatment.pdf", "landing_page_url": "https://dot.nebraska.gov/", "retrieved_at": "2026-08-08T10:30:00.000Z", "original_filename": "ne-ndot-stf.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:21:21.480Z", "enrich_model": "composer-2.5:run-794082a1-4141-4f47-b6ac-158695fc36ae", "enrich_notes": "WQV is the first 0.5 inch of runoff from new pavement (Treatment Drainage Area); alternate sizing uses 0.75-inch, 24-hour WQV discharge (CN=98, Tc=5 min). Infiltration trench/basin minimum soil infiltration 0.5 in/h stated in Chapter 3 summaries; detailed dimensions refer to Appendix P STF Design Guides (not in excerpt). Grass swale ditch slopes 0.5–6% (longitudinal); side slopes no greater than 1:3. Extended dry detention drawdown cited as 24–48 hours with 72-hour maximum.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nh-nhdot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nh-nhdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/nh-nhdot-drainage.json", "document_metadata": { "jurisdiction_name": "New Hampshire", "jurisdiction_level": "state", "state_code": "NH", "document_title": "NHDOT Manual on Drainage Design for Highways", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "HEC-RAS", "Modified Rational Method" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "HEC-HMS", "HEC-RAS", "HY-8", "StormCAD" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "New Hampshire", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "NHDOT Manual on Drainage Design for Highways", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "ping now represents something less than 100 year and generally becomes less accurate with the increasing frequency and intensity", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "............................ 3-10 3.2.1 Rational Method.........................................................................", "page_or_section": null }, { "field": "practice_mentions.swale", "excerpt": "Treatment swales are designed to promote sedimentation and infiltration by providing a minimum hydraulic residence time within the channel under design flow conditions.", "page_or_section": "Section 4.0.3 Open Channel Treatment Practices, 4-6" }, { "field": "practice_mentions.swale", "excerpt": "the NHDES Stormwater Manuals are used for design considerations and maintenance requirements.", "page_or_section": "Section 4.0.3, 4-6" }, { "field": "practice_mentions.bioretention", "excerpt": "Where stormwater can be temporarily impounded safely, such as open space areas, and some parking lot areas, or LID rain gardens; an inlet grate can be used effectively to slowly release water", "page_or_section": "Section 4.0.15 Hydraulic Analysis of Pavement Inlets, 4-33" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Porous pavement consists of pervious asphalt or concrete surfacing with several feet of free draining granular soil installed below the pavement to provide treatment to the infiltrating surface water.", "page_or_section": "Section 4.0.23 Other Underdrain Applications, 4-53" }, { "field": "practice_mentions.wet_pond", "excerpt": "Water Treatment Ponds – Some treatment ponds utilize underdrain between pond segments to collect water infiltrating through the soil.", "page_or_section": "Section 4.0.23 Other Underdrain Applications, 4-53" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Note: These values are approximate references. If needed, contact the NHDOT Geotechnical Section for site specific design infiltration rates.", "page_or_section": "Table 0.a Hydrologic Soil Group Descriptions, 3-9" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NHDOT Manual on Drainage Design for Highways", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.dot.nh.gov/sites/g/files/ehbemt811/files/inline-documents/manual-drainage-design.pdf", "landing_page_url": "https://www.dot.nh.gov/doing-business-nhdot/engineers-consultants/highway-design-manual", "retrieved_at": "2026-08-11T17:59:10.631Z", "original_filename": "nh-nhdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:23:52.728Z", "enrich_model": "composer-2.5:run-9098e2b1-14eb-465c-a758-fd49442b8457", "enrich_notes": "NHDOT highway drainage manual; water-quality treatment swales reference minimum hydraulic residence time under design flow but give no numeric WQv depth, drawdown, or swale geometry. BMP design criteria are deferred to NHDES Stormwater Manuals. HSG Table 0.a lists approximate minimum infiltration rate ranges (in/hr) by soil group—not a single SCM design infiltration rate. Porous pavement described qualitatively as several feet of free-draining granular soil below surfacing with no storage depth in inches.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nh-state", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nh-state/", "data_url": "https://stormwateratlas.com/data/manuals/nh-state.json", "document_metadata": { "jurisdiction_name": "New Hampshire", "jurisdiction_level": "state", "state_code": "NH", "document_title": "Model Stormwater Standards, 2025 update", "version_or_edition": "Draft: May, 2025", "adoption_or_effective_date": null, "last_revised_date": "2025-05", "relationship_to_state_manual": "adopts_state_manual_directly", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 25, 50, 100 ], "water_quality_volume_method": "WQV = (P)(Rv)(A) where P = 1 inch of rainfall, Rv = 0.05 + 0.9(I) where I = percent impervious cover draining to the structure converted to decimal form, and A = total site area draining to the structure", "peak_flow_calculation_method": [ "TR-55" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "raingardens", "bioretention systems", "tree box filters", "subsurface gravel wetlands", "filtration practices", "infiltration practices", "swales", "detention areas" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "latest New Hampshire Stormwater Manual", "page_or_section": "ELEMENT C, Section 2.a, page 2" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "as specified in the latest New Hampshire Stormwater Manual", "page_or_section": "ELEMENT C, Section 2.a, page 2" }, { "field": "document_metadata.state_code", "excerpt": "latest New Hampshire Stormwater Manual", "page_or_section": "ELEMENT C, Section 2.a, page 2" }, { "field": "document_metadata.document_title", "excerpt": "Model Stormwater Standards, 2025 update", "page_or_section": "Title page, page 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "Last Edited: May 2025 1", "page_or_section": "Title page, page 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The site shall be designed to meet the Watershed Protection Standard (WPS) to the Maximum Extent Practicable (MEP) as specified in the latest New Hampshire Stormwater Manual", "page_or_section": "ELEMENT C, Section 2.a, page 2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the 1-inch rainstorm and the 2-year, 10-year, 25-year, and 50-year 24-hour storm events", "page_or_section": "ELEMENT C, Section 2.c, page 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P)(Rv)(A)", "page_or_section": "Table 1, page 9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "qu = unit peak discharge from TR-55 exhibits 4-II and 4-III", "page_or_section": "Table 1, page 9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "SCMs (such as raingardens, bioretention systems, tree box filters, and similar stormwater management landscaping techniques)", "page_or_section": "ELEMENT C, Section 1.b, page 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1 inch of rainfall", "page_or_section": "Table 1, page 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "onsite retention of the first 1-inch of rainfall based on hydrologic soil group (HSG)", "page_or_section": "Element C.2.a, page 4" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Statewide model municipal standards template (placeholder towns). Stored as NH state guidance; municipalities fill in local name when adopting. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://extension.unh.edu/sites/default/files/media/2025-06/stormwater-management-standards.pdf", "landing_page_url": "https://extension.unh.edu/stormwater-center/nh-stormwater-manual", "retrieved_at": "2026-08-07T11:30:42.897Z", "original_filename": "nh-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "manufactured_treatment", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:24:15.089Z", "enrich_model": "composer-2.5:run-be624ebf-1cc2-47a0-aea4-ef7f04476182", "enrich_notes": "Model municipal template references NH Stormwater Manual and UNH Stormwater Center for BMP sizing and pollutant removal; Table 1 gives WQV/GRV formulas only. WPS requires onsite retention of first 1 inch by HSG via UNH tool.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nj-njdot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nj-njdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/nj-njdot-drainage.json", "document_metadata": { "jurisdiction_name": "New Jersey", "jurisdiction_level": "state", "state_code": "NJ", "document_title": "NJDOT Drainage Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "Modified Rational Method" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [ "Bioretention", "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "NJDOT Drainage Design Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Hazard Area Design Flood, which is the 100-year peak discharge increased by 25 percent. State Adopted Flood Studies can be obta", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "a Hydrologic Method‡ Less than 20 Acres Rational Formula or Modified Rational Method Less than 5 Square Miles NRCS* TR-55 Method", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "for the effects of infiltration, detention storage, evapo-transpiration, surface retention, flow routing and interception. The product of C and the average rainfall intensity (I) is the rainfall excess of runoff per acre. The runoff coefficient should be weighted to reflec", "page_or_section": "pp. 17–18" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "B. 1 1/4 inch of rainfall falling uniformly in two hours.", "page_or_section": "12.2 Methodology, page 82" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The basin must be designed so that the design runoff volume is completely infiltrated within 72 hours of the end of the storm.", "page_or_section": "11.2 Methodology, page 76" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The BMP structure must drain in less than 72 hours.", "page_or_section": "11.2 Methodology, page 77" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Beginning at the time of peak storage within the pond, no more than 90% of the total storm volume shall be released over a 24-hour period", "page_or_section": "12.3 Water Quality Treatment Facilities, page 83" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Trapezoidal swale bottom widths should be no less than 2 feet", "page_or_section": "12.3, page 83" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The slope of the swale shall not be less than 0.5 percent", "page_or_section": "12.3, page 83" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The BMP must have a minimum Permeability of 0.2 to 0.5 inches per hour", "page_or_section": "11.2 Methodology, page 77" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NJDOT Drainage Design Manual (August 2006) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.nj.gov/transportation/eng/documents/SEM/pdf/DrainageDesignManual2006s.pdf", "landing_page_url": "https://dot.nj.gov/transportation/eng/documents/RDM/", "retrieved_at": "2026-08-11T17:59:10.565Z", "original_filename": "nj-njdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": 1.25, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:24:46.176Z", "enrich_model": "composer-2.5:run-97583701-8715-4fba-86dd-73557f7dc6a4", "enrich_notes": "NJDOT defers detailed BMP sizing to the NJDEP Stormwater BMP Manual (Sections 11–12). This excerpt gives WQ storm options (1.25 in in 2 hr), infiltration drawdown (72 hr), groundwater-recharge permeability range (0.2–0.5 in/hr, not a single design rate), extended-detention release over 24 hr, and vegetated/biofilter swale geometry (min 0.5% slope, 2 ft bottom width). Manufactured devices must be NJDEP-certified (Table 12-1); no TAPE/NJCAT program name.", "enrich_schema_version": 2, "fields_not_found": [ "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nj-state", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nj-state/", "data_url": "https://stormwateratlas.com/data/manuals/nj-state.json", "document_metadata": { "jurisdiction_name": "New Jersey Department of Environmental Protection (NJDEP)", "jurisdiction_level": "state", "state_code": "NJ", "document_title": "New Jersey Stormwater Best Management Practices Manual — Chapter 5 (Quantity and Quality Standards and Computations) and Chapter 9.7 (Small-Scale Bioretention Systems)", "version_or_edition": "Chapter 5: July 2023; Chapter 9.7: January 2026", "adoption_or_effective_date": "2023-07", "last_revised_date": "2026-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "NJDEP Water Quality Design Storm (WQDS): 1.25 inches of rain falling nonuniformly over 2 hours (N.J.A.C. 7:8-5.5). NRCS methodology is used to compute WQDS runoff volume, peak rate, and hydrograph; BMPs such as small-scale bioretention must store/treat the entire WQDS volume.", "peak_flow_calculation_method": [ "USDA NRCS methodology (NRCS Runoff Equation and Dimensionless Unit Hydrograph; NEH Part 630 Hydrology Chapters 7, 9, 10, 15, and 16)", "NRCS Curve Number (CN) method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Small-scale green infrastructure BMPs (N.J.A.C. 7:8-5.2 Table 5-1 / 5-2)", "Small-scale bioretention systems (rain gardens, stormwater planters, bioswales, tree pits)", "Small-scale infiltration basins", "Green roofs", "Pervious paving systems", "Grass swales", "Cisterns", "Green Infrastructure Manufactured Treatment Devices (Chapter 9.5)", "Manufactured Treatment Devices (non-GI; Chapter 11.3)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "New Jersey Stormwater Best Management Practices Manual July 2023", "page_or_section": "Chapter 5 header" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "specifically required by the NJDEP Stormwater Management rules at N.J.A.C. 7:8 et seq.", "page_or_section": "Chapter 5, Page 1" }, { "field": "document_metadata.state_code", "excerpt": "New Jersey Stormwater Best Management Practices Manual", "page_or_section": "Chapter 5 header" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 5: Stormwater Management Quantity and Quality Standards and Computations... Green Infrastructure BMPs, Chapter 9.7: Small-Scale Bioretention Systems", "page_or_section": "Chapter 5 title; Chapter 9.7 title" }, { "field": "document_metadata.version_or_edition", "excerpt": "New Jersey Stormwater Best Management Practices Manual July 2023... New Jersey Stormwater Best Management Practices Manual January 2026", "page_or_section": "Chapter 5 header; Chapter 9.7 header" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "New Jersey Stormwater Best Management Practices Manual July 2023", "page_or_section": "Chapter 5 header" }, { "field": "document_metadata.last_revised_date", "excerpt": "New Jersey Stormwater Best Management Practices Manual January 2026", "page_or_section": "Chapter 9.7 header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "New Jersey Stormwater Best Management Practices Manual... NJDEP Stormwater Management rules at N.J.A.C. 7:8 et seq.", "page_or_section": "Chapter 5, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "post-construction runoff hydrographs for the current and projected two-, 10- and 100-year storm events, as defined and determined pursuant to N.J.A.C. 7:8-5.7(c) and (d)", "page_or_section": "Chapter 5, Stormwater Runoff Quantity Control Standards, Page 4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "calculations involving the rainfall depths and intensities for the 2-, 10- and 100-year storm events", "page_or_section": "Chapter 5, Page 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "For stormwater runoff quality control, N.J.A.C. 7:8-5.5 requires using 1.25 inches of rain falling nonuniformly in a 2-hour storm event, which is also known as the Water Quality Design Storm (WQDS).", "page_or_section": "Chapter 5, Page 20–21" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Minimum Storage Volume Entire Water Quality Design Storm Volume", "page_or_section": "Chapter 9.7, Water Quality Mechanisms and Corresponding Criteria" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "the Stormwater Management rules at N.J.A.C. 7:8-5.7 allow only the methodology listed below... The USDA Natural Resources Conservation Service (NRCS) methodology, including the NRCS Runoff Equation and Dimensionless Unit Hydrograph as described in Chapters 7, 9, 10, 15 and 16, Part 630 Hydrology, National Engineering Handbook (NEH)", "page_or_section": "Chapter 5, Pages 2–3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The key component of the NRCS runoff equation is the NRCS Curve Number (CN), which is based on soil permeability, surface cover, hydrologic condition and antecedent moisture.", "page_or_section": "Chapter 5, NRCS Methodology section" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "green infrastructure BMPs listed in Table 5-1 or 5-2, as required by N.J.A.C.", "page_or_section": "Chapter 5 example, ~Page 47 reference" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "9.7 SMALL-SCALE BIORETENTION SYSTEMS... The total suspended solids (TSS) removal rate is 80 - 90%", "page_or_section": "Chapter 9.7 introduction" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 9.6: Pervious Paving Systems... Chapter 9.4: Green Roofs... Chapter 9.5 for Green Infrastructure MTDs... Chapter 9.1: Cisterns... small-scale infiltration basin... Grass swales are one of the green infrastructure BMPs listed in Table 5-1 of N.J.A.C. 7:8-5.2", "page_or_section": "Chapter 5 cross-references; Chapter 9.7" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The capacity of the underdrain must be sufficient to allow the system to drain within 72 hours", "page_or_section": "Ch 9.7, page 74" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "If the small-scale bioretention system with underdrain is installed in an area subject to pedestrian traffic, the drain time should be reduced to 24 hours", "page_or_section": "Ch 9.7, page 74" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table (SHWT) must be at least 1 foot below the bottom of the gravel layer", "page_or_section": "Ch 9.7, page 74" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the elevation difference between the basin bottom and the SHWT is 5 ft, which is greater than the 2 ft mimimum separation requirement", "page_or_section": "Ch 9.7 Example 3, page 34" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Since the soil bed must support the growth of the tree, the minimum depth of 18 inches may not be sufficient", "page_or_section": "Ch 9.7, page 22" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "In sloped-bottom systems, the maximum longitudinal slope is 10%", "page_or_section": "Ch 9.7, page 22" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "For the WQDS, the maximum depth of runoff is 18 inches at the down-gradient end of a sloped-bottom system", "page_or_section": "Ch 9.7, page 22" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The water depth above the soil bed should not exceed the maximum design depth of 12 inches", "page_or_section": "Ch 9.7 Example 1, page 23" }, { "field": "practice_mentions.bioretention", "excerpt": "Small-scale bioretention systems are stormwater management", "page_or_section": "Ch 9.7, page 64" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "proposed small-scale infiltration basin", "page_or_section": "Ch 5, page 54" }, { "field": "practice_mentions.swale", "excerpt": "Bioretention Swale", "page_or_section": "Ch 9.7, page 22" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Note that an MTD is used for pretreatment so that exfiltration may be used", "page_or_section": "Ch 9.7, page 19" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Multi-chapter excerpt (Ch5 July 2023 calculations/standards + Ch9.7 Jan 2026 small-scale bioretention), not the full NJ BMP Manual. WQDS (1.25 in/2-hr) and quantity storms (2-/10-/100-year current and projected) are from Ch5; GI BMP inventory is incomplete relative to the full Chapter 9 series. N.J.A.C. 7:8-5.7 requires NRCS methodology but does not mandate a specific software package (HydroCAD appears only in worked examples). TR-55 is cited as superseded by NEH Part 630.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories (complete Chapter 9 GI catalog beyond practices named in this Ch5/9.7 excerpt)" ] }, "source": { "document_url": "https://dep.nj.gov/wp-content/uploads/stormwater/bmp/njswbmp-chapter-9.7-small-scale-bioretention-systems-january-2026.pdf", "landing_page_url": "https://dep.nj.gov/stormwater/stormwater-management/bmp-manual/", "retrieved_at": "2026-08-08T10:25:00.000Z", "original_filename": "nj-state.txt" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 10, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "infiltration_basin", "manufactured_treatment", "swale" ], "enriched_at": "2026-08-13T09:25:36.022Z", "enrich_model": "composer-2.5:run-7e4c60e5-7efa-4db1-b6b1-535216dde8a2", "enrich_notes": "WQDS is referenced throughout Ch. 5 and 9.7 but the 1.25-inch rainfall depth appears only in atlas/regulatory summary, not in the supplied excerpts. Underdrain bioretention must drain within 72 hours (24 hours where subject to pedestrian traffic). SHWT must be at least 1 ft below the gravel layer (underdrain systems); Example 3 cites a separate 2 ft minimum separation between basin bottom and SHWT for infiltration-type bioretention. Design infiltration uses half of tested saturated hydraulic conductivity in Hantush examples (e.g., 1 in/hr from 2 in/hr), not a single manual-wide rate. Bioretention swale WQDS allows up to 18 in runoff depth at the down-gradient end; planter examples cap surface ponding at 12 in above the soil bed.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nm-nmdot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nm-nmdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/nm-nmdot-drainage.json", "document_metadata": { "jurisdiction_name": "New Mexico", "jurisdiction_level": "state", "state_code": "NM", "document_title": "NMDOT Drainage Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "NRCS / SCS Curve Number (TR-55)", "HEC-HMS", "HEC-RAS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-RAS" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "NMDOT Drainage Design Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "6 Figure 402-18 Bulking Factors for the 100-year Peak Discharge for Natural Channels ...... 4—57 Figure 402-19 Estimated Bulking", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": ".............................. 4—79 404 NRCS Simplified Peak Discharge Method ..............................................", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drain Time Rural and Urban - must drain in less than 96 hours (a)", "page_or_section": "Table 207-1 Criteria for Detention and Retention Ponds, page 2-14" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Retention ponds must be designed to drain completely in 96 hours.", "page_or_section": "Section 506.7 Retention Storage Facilities, page 5-124" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Drain Time Rural and Urban - must drain in less than 96 hours (a)", "page_or_section": "Table 207-1 DETENTION PONDS, page 2-14" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The pond must drain via infiltration in less than 96 hours to meet the New Mexico Office of the State Engineer water rights requirements.", "page_or_section": "Section 701 MS4, page 7-10" }, { "field": "practice_mentions.wet_pond", "excerpt": "Retention storage facilities which may have a permanent pool (wet pond) are often discouraged", "page_or_section": "Section 506.7, page 5-123" }, { "field": "practice_mentions.swale", "excerpt": "Gutter sections can be categorized as conventional or shallow swale type as illustrated in Figure 504-1.", "page_or_section": "Section 504.2.1 Curb and Gutter, page 5-56" }, { "field": "practice_mentions.extended_detention", "excerpt": "DETENTION PONDS (Non-Jurisdictional) ... Drain Time Rural and Urban - must drain in less than 96 hours", "page_or_section": "Table 207-1, page 2-14" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NMDOT Drainage Design Manual (July 2018) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://api.realfile.rtsclients.com/PublicFiles/f260a66b364d453e91ff9b3fedd494dc/ae005670-a671-480e-9c33-0e37cf2f6b82/Drainage%20Design%20Manual%202018.pdf", "landing_page_url": "https://www.dot.nm.gov/infrastructure/program-management/drainage-design/", "retrieved_at": "2026-08-11T17:59:10.635Z", "original_filename": "nm-nmdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 96, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 96, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:26:06.602Z", "enrich_model": "composer-2.5:run-e03cdb86-07d2-4a47-865b-90b93c43f27c", "enrich_notes": "MS4 stormwater quality uses location-specific 80th/90th percentile rainfall depths (Table 207-2, Table 701-1), not a single statewide WQv depth. Albuquerque 90th percentile explicitly 0.615 in per EPA/Kosco direction. Detention and retention (non-jurisdictional) both require drain/infiltrate-evaporate in less than 96 hours; Section 701 ties retention pond drain to NMOSE water rights. GI/LID referenced; no numeric BMP sizing for bioretention, permeable pavement, or MTD verification in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ny-nysdot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ny-nysdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ny-nysdot-drainage.json", "document_metadata": { "jurisdiction_name": "New York", "jurisdiction_level": "state", "state_code": "NY", "document_title": "NYSDOT Highway Design Manual Chapter 8", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "NYSDOT Highway Design Manual Chapter 8", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "lustrates the flood hazard area and the 100 year flood plain. HIGHWAY DRAINAGE 8-13 Exhibit 8-2 Flood Hazard Area From FEMA 480", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "f Runoff Coefficient (C) for Use in the Rational Method ........................................ 26 Exhibit 8-5 k Values for Var", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "Retention facilities which provide for slow release of stormwater over an extended period of several days or more are referred to as extended detention facilities.", "page_or_section": "HIGHWAY DRAINAGE 8-122, Section 8.7.7 Storage Facilities" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "In addition to extended detention facilities, retention facilities include infiltration basins, and swales.", "page_or_section": "HIGHWAY DRAINAGE 8-122, Section 8.7.7 Storage Facilities" }, { "field": "practice_mentions.swale", "excerpt": "Outfalls include discharges from pipes, ditches, swales, and other points of concentrated flow.", "page_or_section": "HIGHWAY DRAINAGE 8-122–123, Section 8.8.5 MS4 Stormwater Outfall Inventory Mapping" }, { "field": "practice_mentions.swale", "excerpt": "A gutter section without curb may be considered a shallow swale section, is formed as detailed on Standard Sheet 624-01", "page_or_section": "HIGHWAY DRAINAGE 8-86, Section 8.7.3 Gutters" }, { "field": "ed_drain_time_hours", "excerpt": "extended period of several days or more", "page_or_section": "Section 8.7.7 Storage Facilities (no hours specified)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NYSDOT Highway Design Manual Chapter 8 — Highway Drainage Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.dot.ny.gov/divisions/engineering/design/dqab/hdm/hdm-repository/chapt_08.pdf", "landing_page_url": "https://www.dot.ny.gov/divisions/engineering/design/dqab/hdm/chapter-8", "retrieved_at": "2026-08-11T17:59:10.600Z", "original_filename": "ny-nysdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T09:28:14.488Z", "enrich_model": "composer-2.5:run-1df27888-f179-4442-b04a-4bf7d103c7fa", "enrich_notes": "Chapter 8 is highway drainage (culverts, gutters, inlets, legal/policy). Section 8.7.7 classifies storage: detention (peak reduction, complete drain after design storm), recharge/leaching basins (GDP-8, RR-157), retention via evaporation/infiltration only; extended detention defined qualitatively as slow release over several days or more. No explicit WQv depth, drawdown hours, SHWT separation, or SCM dimensional criteria in provided excerpts. Private connections may require retention/detention to pre-development rate (policy, no numeric SCM specs).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nyc-ny", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nyc-ny/", "data_url": "https://stormwateratlas.com/data/manuals/nyc-ny.json", "document_metadata": { "jurisdiction_name": "New York City", "jurisdiction_level": "municipality", "state_code": "NY", "document_title": "New York City Stormwater Manual Appendix", "version_or_edition": "Appendix to Chapter 19.1 of Title 15 of the Rules of the City of New York published as final on February 1, 2024", "adoption_or_effective_date": "2024-02-01", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 10 ], "water_quality_volume_method": "The volume of runoff from the 90th percentile rain event (1.5 inches of rainfall in New York City), calculated using contributing area and a runoff coefficient based on percent impervious cover.", "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "EPA SWMM" ], "approved_bmp_categories": [ "Infiltration Systems", "Evapotranspiration (ET) Systems", "Reuse Systems", "Filtration Systems", "Detention Systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "NEW YORK CITY STORMWATER MANUAL APPENDIX", "page_or_section": "Page I" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Rules of the City of New York", "page_or_section": "Page I" }, { "field": "document_metadata.state_code", "excerpt": "New York State Department of Environmental Conservation", "page_or_section": "Page II" }, { "field": "document_metadata.document_title", "excerpt": "NEW YORK CITY STORMWATER MANUAL APPENDIX", "page_or_section": "Page I" }, { "field": "document_metadata.version_or_edition", "excerpt": "published as final on February 1, 2024", "page_or_section": "Page I" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "published as final on February 1, 2024", "page_or_section": "Page I" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "meeting the NYC SWM criteria does not obviate the need for a full review of and compliance with NYSDEC SWMDM requirements, as applicable.", "page_or_section": "Page 1-3" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "sites must manage the peak rate of runoff for the 10YR rainfall event ... based on a rainfall event with a 5 yr. return period", "page_or_section": "Pages 2-17, 2-18" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The volume of runoff from the 90th percentile rain event, which must be managed by SMPs, is also referred to as the water quality volume (WQV) ... In New York City, the 90th percentile rain event is 1.5 inches of rainfall", "page_or_section": "Page 2-13" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "of the rainfall event. It is used primarily for sewer design. For New York City areas of 10 square miles or less these assumptions are considered valid. For areas greater than 10 square miles, other modeling techniques may be more appropriate. Development Activity: Creation", "page_or_section": "p. 8" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Acceptable stormwater models include HydroCAD and EPA SWMM.", "page_or_section": "Page 4-7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Systems ... Evapotranspiration (ET) Systems ... Reuse Systems ... Filtration Systems ... Detention Systems", "page_or_section": "Page CONTENTS" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "In New York City, the 90th percentile rain event is 1.5 inches of rainfall (see NYS SWMDM).", "page_or_section": "Chapter 2, page 2-13" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "MAX. Drawdown time Surface = 24hr Total = 48hr", "page_or_section": "Table 4.2, page 4-17 (Bioretention)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Vertical separation from groundwater / bedrock 3' MIN", "page_or_section": "Table 4.2, page 4-17" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting/filter media depth 2.5' MIN 4' MAX", "page_or_section": "Table 4.2 Bioretention, page 4-17" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Surface ponding depth 12\" MAX", "page_or_section": "Table 4.2 Bioretention, page 4-17" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Stone base depth ... Porous pavement ... 12\" MIN", "page_or_section": "Table 4.2 continued, page 4-18" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "MIN. infiltration rate of underlying soils 0.5 in/hr", "page_or_section": "Table 4.2, page 4-17" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "MAX. Drawdown time Temp. Storage Area = 48hr", "page_or_section": "Table 4.5 Constructed Wetland / Wet Basin, page 4-29" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "bottom width minimum of 2' and no greater than 6'", "page_or_section": "Section 4.10 Vegetated swale supplementary criteria, page 4-97" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Planting/filter media depth ... Green roof 4\" MIN", "page_or_section": "Table 4.3, page 4-21" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [ "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.nyc.gov/assets/dep/downloads/pdf/water/stormwater/unified-stormwater-rule/uswr_nyc_stormwater_manual.pdf", "landing_page_url": "https://www.nyc.gov/site/dep/water/unified-stormwater-rule.page", "retrieved_at": "2026-08-07T11:38:32.226Z", "original_filename": "nyc-ny.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 12, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 4, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:30:05.370Z", "enrich_model": "composer-2.5:run-95bd30d8-e950-4142-9953-a525fae55bc6", "enrich_notes": "NYC WQv uses 90th percentile rainfall of 1.5 in (not runoff depth alone). Vertical separation 3 ft MIN (4 ft in sole source aquifers). Bioretention planting/filter media 2.5 ft MIN (4 ft MAX infiltration); filtration tables show 2.5 ft MIN. Surface ponding 12 in MAX (infiltration bioretention); filtration bioretention 6–12 in; ET rain gardens 3 in MAX. Drawdown: ponding areas generally within 24 hr (dry basin surface 48 hr); infiltration bioretention surface 24 hr / total 48 hr. Detention temp storage drawdown 48 hr (72 hr detention tank; blue roof 24 hr). Porous pavement stone base 12 in MIN. Green roof media 4 in MIN (6 in preferred). Swale bottom width 2–6 ft; bottom slope 0.5–4%; flow depth 4 in MAX when credited for WQv.", "enrich_schema_version": 2, "fields_not_found": [ "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ny-bluebook", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ny-bluebook/", "data_url": "https://stormwateratlas.com/data/manuals/ny-bluebook.json", "document_metadata": { "jurisdiction_name": "New York State", "jurisdiction_level": "state", "state_code": "NY", "document_title": "New York State Standards and Specifications for Erosion and Sediment Control", "version_or_edition": "November 2016", "adoption_or_effective_date": "2016-11", "last_revised_date": "2016-11", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "USDA NRCS TR20" ], "approved_bmp_categories": [ "vegetative", "structural", "Runoff Control", "Soil Stabilization", "Sediment Control" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "New York State Standards and Specifications for Erosion and Sediment Control", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "New York State Standards and Specifications for Erosion and Sediment Control", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "New York State Standards and Specifications for Erosion and Sediment Control", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "New York State Standards and Specifications for Erosion and Sediment Control", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "November 2016", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "November 2016", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "November 2016 Blue Book Corrections", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "New York State Standards and Specifications for Erosion and Sediment Control", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Runoff calculations for 1 and 10-year frequency storms, if required.", "page_or_section": "Page 5.23" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "the shortest allowed with TR-55", "page_or_section": "Page B.1" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "These data can be imported into HydroCAD, USDA NRCS TR20, and other computer models", "page_or_section": "Page 1.5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "ESC practices are categorized as vegetative and/or structural controls.", "page_or_section": "Page 2.2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "refer to NYS Stormwater Management Design Manual, Chapters 3 and 5", "page_or_section": "page 21, SITE PLANNING" }, { "field": "design_parameters.infiltration_basin", "excerpt": "implementation of standard stormwater treatment practices such as infiltration basins and others", "page_or_section": "page 33, Design Process for ESC Plans" }, { "field": "practice_mentions.swale", "excerpt": "Energy dissipation with check dams, drop structures, and possibly turf reinforcement in swales and ditches", "page_or_section": "page 30, Site Improvements Stage" }, { "field": "practice_mentions.swale", "excerpt": "Perimeter Dike/Swale Divert runoff Drainage area ≤ 5 Ac.", "page_or_section": "Table 2.2, page 37" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "embankments and grading for wetland restoration projects", "page_or_section": "page 32, Water Resources Projects" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "sediment traps and basins should have their temporary storage dewatered over a 48 hour period", "page_or_section": "page 5.10, Dewatering Drawdown (sediment control—not assigned to SCM max drawdown field)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "The document references the separate 'New York State Stormwater Management Design Manual' for post-construction runoff reduction and water quality volume maintenance, leaving the local water quality volume method null in this erosion-and-sediment-focused manual.", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.dec.ny.gov/fs/docs/pdf/erosionsediment_bluebook.pdf", "landing_page_url": "https://dec.ny.gov/environmental-protection/water/water-quality/stormwater/construction-stormwater-toolbox", "retrieved_at": "2026-08-07T21:19:23.959Z", "original_filename": "ny-bluebook.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "infiltration_basin", "swale" ], "enriched_at": "2026-08-13T09:27:43.924Z", "enrich_model": "composer-2.5:run-c4ce276f-3637-4a66-b05a-70dcb9f0194b", "enrich_notes": "Document is NYS erosion and sediment control (Bluebook), not the NYS Stormwater Management Design Manual. Post-construction runoff reduction, WQV, and BMP sizing are deferred to that manual (Ch. 3 and 5). Excerpts mention infiltration/filtration facilities during construction sequencing, perimeter and interceptor swales, wetland restoration as project type, and sediment-trap dewatering (48 hr minimum, up to 7 days for high-fines soils)—not mapped SCM design parameters. Construction road guidance prefers routes where seasonal water table is deeper than 18 inches (road siting, not BMP SHWT separation). Subsurface drain standard uses 1 inch removed in 24 hours drainage coefficient.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ny-state", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ny-state/", "data_url": "https://stormwateratlas.com/data/manuals/ny-state.json", "document_metadata": { "jurisdiction_name": "New York State", "jurisdiction_level": "state", "state_code": "NY", "document_title": "STORMWATER MANAGEMENT DESIGN MANUAL", "version_or_edition": "July 31, 2024", "adoption_or_effective_date": "2024-07-31", "last_revised_date": "2024-07-31", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "90% Rule: WQv (acre-feet) = (P * Rv * A) / 12, where Rv = 0.05 + 0.009(I)", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "USDA NRCS TR20", "HydroCAD", "Pond Pack", "StormCAD", "Hydraflow", "HEC-HMS" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Practices", "Open Channel Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "New York State Department of Environmental Conservation", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "New York State Department of Environmental Conservation", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "DAM SAFETY SECTION 50 WOLF ROAD ALBANY, NEW YORK 12233-3507 --- page 369 --- GUIDELINES FOR DESIGN OF DAMS TABLE OF CONTENTS SECTION TITLE PAGE Preface to the January 1 1989 Edition 1 Introduction 2 Gravity Dams Modification 2 Definitions 3 3 Hazard Classification 5 4 De", "page_or_section": "pp. 363–370" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT DESIGN MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The New York State Stormwater Design Manual is prepared to provide standards for the design of the Stormwater Management Practices", "page_or_section": "Preface" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-year, 2-year, 10-year, and 100-year", "page_or_section": "Table 4.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQv) 90% Rule: WQv (acre-feet) = (P ∙ Rv ∙ A) / 12 Rv = 0.05+0.009(I) I = Impervious Cover (Percent) P(inches) = 90% Rainfall Event Number (See Figure 4.1) 2 A = Contributing Area (acres) Runoff Reduction Volume (RRv) RRv (acre-feet) = Reduction of", "page_or_section": "p. 43" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "TR-55 and TR-20 (or approved equivalent) shall be used to determine peak discharge rates.", "page_or_section": "Section 4.6" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Hydraulic and hydrologic modeling software, such as USDA NRCS TR20, HydroCAD, Pond Pack, StormCAD, Hydraflow, and Hydrologic Engineering Center Hydrologic Modeling System (HEC-HMS) and others, shall be used", "page_or_section": "Section 4.9" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Acceptable practices are divided into five groups, including: I. Stormwater Ponds... II. Stormwater Wetlands... III. Infiltration Practices... IV. Filtering Practices... V. Open Channel Practices", "page_or_section": "Section 3.3.1" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "90th percentile rainfall 1.20 inches (Section 4.2)", "page_or_section": "Chapter 7, Table 7.1, page 7-1" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Tree trenches and tree pits with more than one tree per pit shall have a 2 ft min. separation to the seasonal high water table and bedrock", "page_or_section": "Section 5.3.3.1, page 5-38 area" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Infiltration rain gardens shall have a 12 inch minimum and 18 inch maximum filter media depth", "page_or_section": "Fact Sheet: Rain Garden (RR-6), page 5-60" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum ponding depth shall be 12 inches during the WQv event and 18 inches during the Extreme Flood event", "page_or_section": "Fact Sheet: Rain Garden (RR-6), page 5-60" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rain gardens shall have underlying soils with an infiltration rate greater than or equal to 0.50 inch/hr", "page_or_section": "Fact Sheet: Rain Garden (RR-6), page 5-60" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size outlet structure to detain WQv for 24 hrs (12 hrs to trout waters)", "page_or_section": "Fact Sheet: Wet Pond (P-2), page 6-15" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Min. flow path of 1.5:1 (length to relative width) from all inlet points to the outflow points across the pond", "page_or_section": "Fact Sheet: Wet Pond (P-2), page 6-15" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width shall be a min of 2 ft and a max of 8 ft", "page_or_section": "Fact Sheet: Dry Swale (O-1), page 6-77" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://dec.ny.gov/fs/projects/24-25DraftCGPDesignManual/Manual.SW.CGP.2024-07-31.Design_Manual_Issued_2024-07-31.pdf", "landing_page_url": "https://dec.ny.gov/environmental-protection/water/water-quality/stormwater/construction-stormwater-toolbox", "retrieved_at": "2026-08-07T11:24:29.820Z", "original_filename": "ny-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:29:07.432Z", "enrich_model": "composer-2.5:run-7155a008-72b8-4f5e-bcde-f4804d418e3c", "enrich_notes": "WQv uses 90th-percentile rainfall P (example 1.20 in). WQv extended detention is 24 hr (12 hr in trout waters). SHWT separation commonly 2 ft (4 ft sole-source aquifer for some practices). Rain garden infiltration filter media 12–18 in; SMP bioretention 30–48 in. Micropool depth 3–8 ft is not the same as permanent-pool depth. Infiltration feasibility threshold 0.50 in/hr cited throughout; pond liner soils fc ≤ 0.014 in/hr.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nc-state", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nc-state/", "data_url": "https://stormwateratlas.com/data/manuals/nc-state.json", "document_metadata": { "jurisdiction_name": "North Carolina Department of Environmental Quality (NCDEQ)", "jurisdiction_level": "state", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual — C-0. Minimum Design Criteria for all SCMs", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Combined design volume of all SCMs must handle the required storm depth for the applicable stormwater program (depth varies by rule). Example: Rule 15A NCAC 02H .1021(6) requires a one-inch storm depth for runoff treatment in non-coastal HQW and ORW management zones. Design volume accounts for build-out runoff from all surfaces draining to the system; off-site drainage may be bypassed. Volume calculation methods are in Part B of the full manual (not in this chapter).", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "Berms", "SCM-specific devices per Rules 15A NCAC 02H .1051–.1062 (Part C)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "NCDEQ Stormwater BMP Manual", "page_or_section": "Header, C-0" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Rule 15A NCAC 2H .1050. MDC for All Stormwater Control Measures", "page_or_section": "Important Links, Page 1" }, { "field": "document_metadata.state_code", "excerpt": "NCDEQ Stormwater BMP Manual", "page_or_section": "Header" }, { "field": "document_metadata.document_title", "excerpt": "C-0. Minimum Design Criteria for all SCMs", "page_or_section": "Page 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "C-0. MDC for all SCMs 1 Revised: 1-3-2017", "page_or_section": "Page header" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised: 1-3-2017", "page_or_section": "Page header" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised: 1-3-2017", "page_or_section": "Page header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This chapter contains Minimum Design Criteria (MDC) that apply to all Stormwater Control Measures (SCMs)... See Part C of this Manual for SCM-specific requirements.", "page_or_section": "Design Objective, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The outlets of SCMs shall be designed so that they do not cause erosion immediately downslope of the discharge point during the peak flow from the 10-year storm event as shown by engineering calculations.", "page_or_section": "GENERAL MDC 4: EROSION PROTECTION, Page 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The combined design volume of all SCMs on the project shall be sufficient to handle the required storm depth... Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING, Page 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement, and depending upon native soils, vegetated swales, level spreader-filter strips, and berms.", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS, Page 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Every SCM shall follow the applicable device specific MDC pursuant to Rules .1051 through .1062 of this Section.", "page_or_section": "GENERAL MDC 13, Page 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" }, { "field": "practice_mentions.bioretention", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.swale", "excerpt": "and depending upon native soils, vegetated swales, level spreader-filter strips, and berms.", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" }, { "field": "practice_mentions.wet_pond", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice at the invert", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Recommend pumping down wet ponds and wetlands rather than using a drawdown orifice at the invert", "page_or_section": "GENERAL MDC 6: DEWATERING., page 3" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS., page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Source is chapter C-0 only (MDC for all SCMs) of the multi-PDF NCDEQ Stormwater Design Manual. Required storm depth and SCM-specific MDC live in other parts/rules; this chapter states general sizing, outlet 10-year peak erosion protection, and lists example infiltrating SCM types. Peak-flow calculation methods and required software are not specified here (volume methods referred to Part B).", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.deq.nc.gov/about/divisions/energy-mineral-and-land-resources/stormwater/stormwater-program/stormwater-design-manual", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "nc-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:20:27.736Z", "enrich_model": "composer-2.5:run-5c9a3245-f752-477e-9bc2-c3ec4e469d8b", "enrich_notes": "Source is NCDEQ Manual C-0 (general MDC only). Required storm depth varies by program rule; one inch cited as example for Rule 15A NCAC 02H .1021(6) runoff treatment in non-coastal HQW/ORW zones—not a universal statewide WQv depth. Runoff volume methods are in Part B; device-specific numeric MDC are in Part C / Rules .1051–.1062. Dewatering is required but no maximum drawdown hours. Outlet erosion design uses 10-year storm peak flow, not a listed WQ depth field.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nc-ncdot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nc-ncdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/nc-ncdot-drainage.json", "document_metadata": { "jurisdiction_name": "North Carolina Department of Transportation (NCDOT)", "jurisdiction_level": "state", "state_code": "NC", "document_title": "Guidelines for Drainage Studies and Hydraulic Design", "version_or_edition": "2022", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 50 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS" ], "approved_bmp_categories": [ "Filter Strip" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "North Carolina Department of Transportation (NCDOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Guidelines for Drainage Studies and Hydraulic Design", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the roadway shoulder of two feet for a 50-year impoundment level; • A means of draining the lake completely will be provided.", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ations for future urbanization values o Rational Method ‘c’ values o design frequencies for different facility types • Pipes o a", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Filter Strip", "page_or_section": null }, { "field": "practice_mentions.swale", "excerpt": "Encroachments that impact NCDOT non-swale BMP facilities should be considered on a case-by-case basis", "page_or_section": "2.4.12 Stormwater BMP Facilities within NCDOT Right-of-Way (page 31)" }, { "field": "practice_mentions.swale", "excerpt": "complete the ... stormwater control measure tabs (swales, filter strip, PSHs and energy dissipators, level spreader and HSB, other toolbox BMPs, other non-toolbox BMPs)", "page_or_section": "5.5.2 Stormwater Control Measure Summary Sheets (pages 90-91)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "field data collection, such as seasonal high-water table, infiltration rates, or other design parameters", "page_or_section": "13.4.2.7 / NC-SELDM BMPtoolbox guidance (page 265)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "field data collection, such as seasonal high-water table, infiltration rates, or other design parameters", "page_or_section": "13.4.2.7 / NC-SELDM BMPtoolbox guidance (page 265)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NCDOT Guidelines for Drainage Studies and Hydraulic Design (2022 archived PDF; live guidance is web-based)", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://connect.ncdot.gov/resources/hydro/DrainageStudiesGuidelines/2022%20Guidelines%20for%20Drainage%20Studies%20and%20Hydraulic%20Design.pdf", "landing_page_url": "https://connect.ncdot.gov/resources/hydro/Pages/DrainageStudiesGuidelines.aspx", "retrieved_at": "2026-08-11T17:21:06.002Z", "original_filename": "nc-ncdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T09:20:04.785Z", "enrich_model": "composer-2.5:run-8408bed2-804b-4f2a-91c9-432214843266", "enrich_notes": "Provided excerpts cover NCDOT Guidelines policy (NPDES, BMP in ROW, SMP/pSMP workflow, NC-SELDM Catalog, BMP Toolbox manual references) but do not state numeric SCM sizing criteria (WQv depth, drawdown, media depths, infiltration design rates, pool depths, swale dimensions). Atlas notes Filter Strip; SMP template lists swales and filter strip among SCM tabs—detailed parameters likely in BMP Toolbox manual or Chapter 13 sections not included here.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "nd-nddot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/nd-nddot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/nd-nddot-drainage.json", "document_metadata": { "jurisdiction_name": "North Dakota", "jurisdiction_level": "state", "state_code": "ND", "document_title": "NDDOT Design Manual Chapter V", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "HEC-HMS", "HEC-RAS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS", "HEC-RAS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "North Dakota", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "NDDOT Design Manual Chapter V", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "). 10. Type of precipitation. V–01.03.2 100-Year Frequency Discharges for 100 year frequencies and associated water surface elev", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Drainage Systems Section 3: Appendix A: Rational Method Runoff Coefficients Section 3: Appendix B: Time of Concentration of Smal", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "The entire discharge hydrograph shall be used for the design of facilities which are intended to control volume of runoff, such as detention facilities.", "page_or_section": "Section V-01 Hydrology, page 1 (V–01 intro)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. NDDOT Design Manual Chapter V — Hydraulic Studies and Drainage Design", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.dot.nd.gov/sites/www/files/documents/Design/Chapter%205.pdf", "landing_page_url": "https://www.dot.nd.gov/construction-and-planning/construction-and-contractor-resources/design-manual", "retrieved_at": "2026-08-11T17:59:10.627Z", "original_filename": "nd-nddot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention" ], "enriched_at": "2026-08-13T09:20:49.425Z", "enrich_model": "composer-2.5:run-070200e9-f2c8-4982-9402-a50dff2d8f49", "enrich_notes": "NDDOT Design Manual Chapter V focuses on highway hydrology (USGS regression, Rational Method for urban areas under 200 acres with NOAA Atlas 14), bridges/box culverts, pipe culverts, and permits. Volume-control facilities are referenced only generically; no water-quality volume depth, infiltration SCM sizing, or BMP-specific design criteria appear in the supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "arkansas-manual", "processed_at": "2026-08-17T03:19:55.594Z", "detail_url": "https://stormwateratlas.com/arkansas-manual/", "data_url": "https://stormwateratlas.com/data/manuals/arkansas-manual.json", "document_metadata": { "jurisdiction_name": "Northwest Arkansas (NWA MS4s)", "jurisdiction_level": "other", "state_code": "AR", "document_title": "Stormwater Pollution Prevention, Grading, and Erosion Control Best Management Practices Manual (NWA 2016 Stormwater BMP Manual)", "version_or_edition": "Revised December 2016 / NWA 2016", "adoption_or_effective_date": "2016-12", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "No explicit post-construction Water Quality Volume (WQv) formula. Construction sediment traps sized by settling-velocity surface area: SA = FS(Q2/VS) with FS=2 and VS=0.00096 fps for 0.02 mm medium silt (SA ≈ 2080 sf per cfs of 2-year developed peak inflow; use 10-year peak when higher protection is warranted). Chemical treatment storage recommended at 1.5× the runoff volume of the 10-year, 24-hour storm. Retention/detention ponds sized to the host municipality’s design storm (or infiltration capacity in karst). LID Appendix B addresses rain gardens, bioretention, infiltration, and green rooftops qualitatively without a regional WQv equation.", "peak_flow_calculation_method": [ "Rational Method", "Hydrologic analysis (developed 2-year, 10-year, and 100-year peak discharges)", "Pre-developed condition runoff methods for allowable discharge rates" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Preserving Natural Vegetation / Buffer Zones", "Wetland Preservation, Creation, and Re-creation", "Floodway and Floodplain Controls", "Dust Prevention and Control", "Material Delivery, Storage, and Containment", "Concrete Waste Management / Washouts", "Saw-Cutting and Surfacing Pollution Prevention", "Gross Solids and Solid Waste / Sanitary Service", "Stabilized Construction Exit / Rumble Strips and Wheel Wash", "Temporary and Permanent Seeding / Mulching / Sodding / Top-soiling", "Nets and Blankets / PAM for Soil Erosion Protection", "Surface Roughening / Gradient Terrace", "Interceptor Dike and Swale / Grass-Lined and Reinforced Channels", "Vegetated Strip / Diversionary Ditch / Pipe-Slope and Subsurface Drains", "Level Spreader / Wattles / Check Dams / Brush Barrier / Gravel Filter Berm", "Storm Drain Inlet Protection / Outlet Protection / Energy Dissipaters", "Secondary Embedded Reinforced Perimeter Sediment Barrier", "Sediment Trap / Temporary Sediment Pond", "Retention / Detention Pond", "De-watering / Turbidity Removal / Chemical Treatments / Filtration", "Low-Impact Development – Rain Gardens / Bioretention / Grassed Swales", "Low-Impact Development – Infiltration / Sand Filtration", "Low-Impact Development – Green Rooftop / Impervious Area Reduction", "Low-Impact Development – Cisterns and Rain Barrels / Undisturbed Water Body Buffer" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Prepared by the Stormwater Compliance Group of Northwest Arkansas. This manual was written for the small Municipal Separate Stormwater Sewer Systems (MS4s) in Northwest Arkansas", "page_or_section": "Executive Summary" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "serve as a common guidance document for the design and implementation of control measures for construction site runoff control and post-construction runoff controls", "page_or_section": "Executive Summary" }, { "field": "document_metadata.state_code", "excerpt": "Stormwater discharges from construction sites must not cause or contribute to violations of Arkansas’s surface water quality standards", "page_or_section": "Introduction" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER POLLUTION PREVENTION, GRADING, AND EROSION CONTROL Best Management Practices Manual ... NWA 2016 Stormwater BMP Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised December 2016 ... NWA 2016 Stormwater BMP Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised December 2016", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "ADEQ expects that the selection and implementation of appropriate BMPs outlined in this or equivalent manuals will result in compliance with water quality standards", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The terrace should have enough capacity to handle the peak runoff expected from a 2-year, 24-hour design storm without overtopping.", "page_or_section": "BMP 261: Gradient Terrace" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Design capacity for the peak flow from a 10-year, 24-hour design storm for temporary facilities.", "page_or_section": "BMP 301: Interceptor Dike and Swale" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Temporary secondary containment facilities shall provide for a spill containment volume able to contain precipitation from a 25 year, 24 hour storm event, plus 10% of the total enclosed container volume", "page_or_section": "BMP 123: Material Containment" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "These outlets must pass the peak runoff expected from the contributing drainage area for a 100-year storm.", "page_or_section": "BMP 402: Temporary Sediment Pond" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "SA = FS(Q2/VS) where Q2 = Design inflow based on the peak discharge from the developed 2-year runoff event ... VS = 0.00096 fps ... SA = 2 x Q2/0.00096 or 2080 square feet per cfs of inflow.", "page_or_section": "BMP 401: Sediment Trap" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "at a minimum the storage pond or other holding area should be sized to hold 1.5 times the runoff volume of the 10-year, 24-hour storm event.", "page_or_section": "BMP 430: Chemical Treatments" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Retention ponds should be sized to hold the entire design storm of the municipality that they are located in, or in more karstic areas, whatever the ground infiltration rate will support.", "page_or_section": "BMP 410: Retention vs. Detention Ponds" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "If no hydrologic analysis is required, the Rational Method may be used.", "page_or_section": "BMP 401: Sediment Trap" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The diameter shall be the minimum necessary to pass the pre-developed 10-year peak flow (Q10). ... Emergency Overflow Spillway: Determine the required size and design of the emergency overflow spillway for the developed 100-year peak flow.", "page_or_section": "BMP 402: Temporary Sediment Pond" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Runoff rates shall be calculated using the methods for the pre-developed condition. If no hydrologic analysis is required for the site, the Rational Method may be used.", "page_or_section": "BMP 430: Chemical Treatments" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Chapter 1: Prevention BMPs ... Chapter 2: Access and Source Control BMPs ... Chapter 3: Conveyance BMPs ... Chapter 4: Treatment BMPs ... Appendix B: Low Impact Development", "page_or_section": "Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bio-retention and grassed swales are common infiltration techniques. ... Rain gardens are landscaped bio-retention facilities ... Green Rooftop is a layer of vegetation, shrubs, or trees planted on rooftops to absorb stormwater runoff.", "page_or_section": "Appendix B: Low-Impact Development" }, { "field": "practice_mentions", "excerpt": "Rain gardens are landscaped bio-retention facilities that soak up runoff displaced by the impervious", "page_or_section": "p98" }, { "field": "practice_mentions.bioretention", "excerpt": "Bio-retention and grassed swales are common infiltration techniques.", "page_or_section": "Appendix B, B.1.2 Infiltration Techniques (page xcvii)" }, { "field": "practice_mentions.bioretention", "excerpt": "Rain gardens are landscaped bio-retention facilities that soak up runoff displaced by the impervious area of a structure.", "page_or_section": "Appendix B, Rain Gardens (page xcviii)" }, { "field": "practice_mentions.swale", "excerpt": "Bio-retention and grassed swales are common infiltration techniques.", "page_or_section": "Appendix B, B.1.2 (page xcvii)" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Rooftop is a layer of vegetation, shrubs, or trees planted on rooftops to absorb stormwater runoff.", "page_or_section": "Appendix B, B.1.3 Impervious Surface Area Reduction (page xcviii)" }, { "field": "practice_mentions.sand_filter", "excerpt": "In areas where local soils do not readily support infiltration, sand filtration systems can be used to discharge treated stormwater to a stream or storm sewer.", "page_or_section": "Appendix B, B.1.2 (page xcvii–xcviii)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Provide an overflow lot utilizing grass or alternative pavers for peak demand parking.", "page_or_section": "Appendix B, Green Parking (page xcviii)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention ponds should also be designed to the standards of the municipality that they are located in", "page_or_section": "BMP 410, Design and Installation Specifications (page lxxxiii)" }, { "field": "practice_mentions.wet_pond", "excerpt": "Retention ponds hold water back. Detention ponds temporarily contain water, or slow release it into drainage ways.", "page_or_section": "BMP 410 (page lxxxii–lxxxiii)" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "One example of a de-watering BMP is a manufactured enclosed filter bag placed on a pervious pavement or material", "page_or_section": "BMP 420 De-watering (page lxxxiii)" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "BMP 103: Wetland Preservation, Creations, and Re-creation", "page_or_section": "Chapter 1 Preventative BMPs (page xiii)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Regional NWA MS4 construction/post-construction BMP guide (also branded for Little Flock ARR040035). Design storms of 2-, 10-, 25-, and 100-year (24-hour) appear throughout conveyance, containment, and sediment-pond criteria. No regional WQv equation; sediment-trap settling-area method and municipal detention standards are the primary quantitative WQ approaches. Rational Method is the fallback when a full hydrologic analysis is not required. No hydrologic/hydraulic software is mandated.", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://cityoflittleflock.com/wp-content/uploads/2024/06/BMP-Manual-1-17-ALL.pdf", "landing_page_url": "https://www.bentonville.ar.gov/422/Stormwater-Management", "retrieved_at": "2026-08-10T07:09:00.000Z", "original_filename": "arkansas-manual.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:26:49.891Z", "enrich_model": "composer-2.5:run-b4eec31e-d9a5-4269-bc05-123fa95c2305", "enrich_notes": "NWA 2016 manual excerpts are construction ESC–focused; post-construction WQv depth and SCM sizing numerics are deferred to host municipalities or qualitative LID in Appendix B. Retention/detention ponds sized to municipal design storms; karst areas by infiltration support. Sediment pond divider and maintenance markers use 12 in. references; rain gardens require 10 ft minimum setback from structures (120 in.), not SHWT. Green rooftops cite 17 lb/sf live-load threshold for structural engineer review, not growing-media depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fl-nwfwmd-erp-ah2", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-nwfwmd-erp-ah2/", "data_url": "https://stormwateratlas.com/data/manuals/fl-nwfwmd-erp-ah2.json", "document_metadata": { "jurisdiction_name": "Northwest Florida Water Management District (NWFWMD)", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II (Northwest Florida Water Management District)", "version_or_edition": "June 28, 2024", "adoption_or_effective_date": "2024-06-28", "last_revised_date": "2024-06-28", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "NWFWMD ERP AH Vol II stormwater quality criteria (Parts II/IV/V) including retention system treatment volume and additional quality standards. Quantity/flood criteria include 10-year floodplain storage and 100-year floodway conveyance limits.", "peak_flow_calculation_method": [ "Stormwater quantity rate and volume controls (Part III)", "Retention / detention routing", "Floodplain / floodway conveyance checks" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems", "Detention systems", "On-line and off-line stormwater systems", "Stormwater quantity / flood control facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Northwest Florida Water Management District (NWFWMD)", "page_or_section": "Title / district handbook" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Florida water management district (ERP Applicant's Handbook Volume II)", "page_or_section": "Chapter 62-330, F.A.C. / district handbook" }, { "field": "document_metadata.state_code", "excerpt": "Northwest Florida Water Management District", "page_or_section": "Title" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT’S HANDBOOK VOLUME II", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "June 28, 2024", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Chapter 62-330, F.A.C. ERP stormwater design", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design Criteria and Guidelines for Retention Systems ... Treatment Volume", "page_or_section": "Part V §5.0" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Stormwater Quantity: Rate and Volume Controls", "page_or_section": "Part III" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention Systems; On-Line and Off-line Stormwater Systems", "page_or_section": "TOC" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "10-year floodplain ... 100-year flood elevation", "page_or_section": "§3.4" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "within 72 hours following a storm event assuming average antecedent moisture conditions", "page_or_section": "5.0.3 Recovery Time (Vol II p. 5-3)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "designed to recover the required treatment volume of stormwater runoff within 72 hours following a storm event", "page_or_section": "5.1.3 Recovery Time (Vol II p. 5-7)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "invert elevation of the trench is at least two feet above the seasonal high ground water table elevation", "page_or_section": "5.1.8 Ground Water Table (Vol II p. 5-9)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The average length to width ratio of the pond must be at least 2:1", "page_or_section": "5.2.8 Pond Configuration (Vol II p. 5-17)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Canonical NWFWMD ERP AH Vol II special_district record. City proxies tallahassee-fl / pensacola-fl remain for municipal map coverage.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://nwfwater.com/wp-content/uploads/2024/07/AHII-nwfwmd-FINAL-2024.pdf", "landing_page_url": "https://nwfwater.com/", "retrieved_at": "2026-08-11T18:38:36.246Z", "original_filename": "fl-nwfwmd-erp-ah2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:15:34.842Z", "enrich_model": "composer-2.5:run-aaba60e3-db0c-487e-9997-843df3a50e32", "enrich_notes": "Treatment volume is tied to Vol I §8.3/§9 efficiency, not a fixed WQv depth in this excerpt. Retention and exfiltration recovery is 72 h at average AMC; exfiltration may use SF=2 (half infiltration rate or 36 h drawdown). Wet detention draws down half the treatment volume in 48–60 h; permanent pool sized for 21-day residence (wet-season rainfall). Exfiltration trench invert ≥2 ft above seasonal high GW; min 3 ft trench width, 2 in min pipe ID. Swales: HSG A/B, 3-year 1-hour storm infiltration, cross-section top width:depth ≥6:1 or side slopes ≤3:1 H:V. Wet pond max depth 12 ft; L:W ≥2:1. Base flow: storage volumes exclude volume below seasonal high water table (no minimum separation inches for ponds in excerpt).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ohio-rainwater", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/ohio-rainwater/", "data_url": "https://stormwateratlas.com/data/manuals/ohio-rainwater.json", "document_metadata": { "jurisdiction_name": "Ohio", "jurisdiction_level": "state", "state_code": "OH", "document_title": "Rainwater and Land Development: Ohio's Standards for Stormwater Management, Land Development and Urban Stream Protection", "version_or_edition": "Third Edition 2006", "adoption_or_effective_date": "2006-12-01", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Water quality volume (WQv) is the volume of runoff treated in a water quality pond, calculated as WQv (ac-ft) = C × 0.75 × A / 12 (Equation 1, adapted from ASCE/WEF Urban Runoff Quality Management), where C is the runoff coefficient from site imperviousness (Equation 2: C = 0.858i² – 0.78i + 0.773i + 0.04, with i = percent imperviousness / 100) and A is drainage area in acres—equivalent to treating runoff from 0.75 inch of precipitation. Ohio EPA NPDES permit requires 20% additional WQv capacity for sediment accumulation; extended detention volume equals WQv and is drawn down over 24–48 hours.", "peak_flow_calculation_method": [ "NRCS Technical Release 55 (TR 55)", "USGS empirical equations for small urban streams in Ohio (Sherwood 1986)", "Manning's Equation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Reduction of Impervious Areas", "Low Impact Development", "Conservation Development", "Wetland Setback", "Stream Setback Area", "Water Quality Ponds", "Infiltration Trench", "Sand & Organic Filter", "Grass Filter", "Bioretention Area", "Grassed Swale", "Level Spreader", "Rock Lined Channel", "Rock Outlet Protection", "Diversion", "Terrace", "Subsurface Drainage" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Rainwater and Land Development Ohio's Standards for Stormwater Management", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This book defines Ohio's standards and specifications for stormwater practices implemented during land development.", "page_or_section": "Abstract" }, { "field": "document_metadata.state_code", "excerpt": "Ohio Department of Natural Resources Division of Soil and Water Conservation Columbus, Ohio 43229-6605", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Title: Rainwater and Land Development: Ohio's Standards for Stormwater Management, Land Development and Urban Stream Protection", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Third Edition 2006", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This book defines Ohio's standards and specifications for stormwater practices implemented during land development.", "page_or_section": "Abstract" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Storm Event Return Interval (years) 2 5 10 25 50 100 ... 1-year 2-year 5-year 10-year 25-year 50-year 100-year", "page_or_section": "Chapter 1, Table 1.1.2; Bioretention Design Checklist" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The water quality volume (WQv) is the volume of runoff that is treated in a water quality pond. WQv (ac-ft) = C * 0.75 * A / 12 ... C = 0.858i² – 0.78i + 0.773i + 0.04 ... the Ohio EPA NPDES stormwater general permit for construction activities requires that the water quality volume be increased by 20% for capacity lost over time due to sediment accumulation.", "page_or_section": "Chapter 2, Section 2.6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "NRCS Technical Release 55 (TR 55) or other suitable method shall be used to determine ... peak discharges were estimated using empirical equations developed by the U.S. Geological Survey (Sherwood, 1986)", "page_or_section": "Chapter 4; Chapter 1, Table 1.1.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "2.6 Water Quality Ponds; 2.7 Infiltration Trench; 2.8 Sand & Organic Filter; 2.9 Grass Filter; 3.0 Bioretention Area; 2.1 Reduction of Impervious Areas; 2.2 Low Impact Development; 2.3 Conservation Development", "page_or_section": "Chapter 2 Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 0.75 inch precipitation depth", "page_or_section": "CHAPTER 2 Bioretention Design Checklist, page 83" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv (ac-ft) = C * 0.75 * A / 12 (Equation 1)", "page_or_section": "CHAPTER 2 Water Quality Volume, pages 37 / 376" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "leave at least 4 feet between the seasonal high-water table or bedrock and the trench bottom", "page_or_section": "2.7 Infiltration Trench, page 51" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a minimum 4ft of separation required between the water table and the bioretention practice", "page_or_section": "2.10 Bioretention, page 77" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "ds = planting soil depth (2.5 feet minimum)", "page_or_section": "2.10 Bioretention Design Checklist, page 84" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "minimum recommended width of the landscaped ponded area shall be 10 feet, with the length generally exceeding 2:1 (length:width)", "page_or_section": "2.10 Bioretention, page 80" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "draw down the extended detention volume over a 48-hour period (dry ED); over a 24-hour period (wet ED)", "page_or_section": "Dry/Wet Extended Detention Basin, pages 40–41 / 377–378" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Ohio EPA requires ... minimum drawdown time of 40 hours (bioretention); drained over a 24-48 hour period (ponds)", "page_or_section": "CHAPTER 2 ponds and bioretention, pages 37 / 79" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil infiltration rates within the trench must be between 0.52 and 2.5 inches per hour", "page_or_section": "2.7 Infiltration Trench, page 50" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/epa.ohio.gov/Portals/35/storm/technical_assistance/ARCHIVE-RaLD-2006.pdf", "landing_page_url": "https://epa.ohio.gov/divisions-and-offices/surface-water/guides-manuals/rainwater-and-land-development", "retrieved_at": "2026-08-07T12:55:00.000Z", "original_filename": "ohio-rainwater.pdf" }, "design_parameters": { "wqv_depth_inches": 0.75, "max_drawdown_hours": null, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:32:16.147Z", "enrich_model": "composer-2.5:run-1a454c51-3425-40b5-9d5a-312abedf78bb", "enrich_notes": "WQv uses 0.75 in precipitation depth (Equation 1 / checklist P=0.75 inch). OCR in source often replaces digits with placeholder characters; values above follow clear manual intent (e.g. 48 hr dry ED, 24 hr wet ED, 40 hr bioretention min drawdown). Infiltration trench soils must be 0.52–2.5 in/hr (range, no single design rate). Permanent pool mean depth 3–6 ft (wet ED) and wetland pool 6–18 in general range are not reduced to one scalar.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "oh-odot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/oh-odot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/oh-odot-drainage.json", "document_metadata": { "jurisdiction_name": "Ohio Department of Transportation (ODOT)", "jurisdiction_level": "state", "state_code": "OH", "document_title": "Location & Design Manual, Volume 2 — Drainage Design", "version_or_edition": "July 2022", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": "Water Quality Volume WSE Water Surface Elevation Reference Documents AASHTO Model Drainage Manual (2005) AASHTO Drainage Manual Volume 1 - Policy (2014) Highway Hydrology (FHWA Hydraulic Design Series No", "peak_flow_calculation_method": [ "Rational Method", "HEC-RAS", "USGS regression equations" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS" ], "approved_bmp_categories": [ "Infiltration Basin", "Extended Detention", "Filter Strip", "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Ohio Department of Transportation (ODOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Location & Design Manual, Volume 2 — Drainage Design", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "atory standard also referred to as the \"100-year flood\" or the “1% AEP flood.” The base flood is the national standard used by t", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "and ground cover, which is used in the Rational formula to determine the amount of a rainfall which is directed to streams and", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume WSE Water Surface Elevation Reference Documents AASHTO Model Drainage Manual (2005) AASHTO Drainage Manual Volume 1 - Policy (2014) Highway Hydrology (FHWA Hydraulic Design Series No", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Infiltration Basin, Extended Detention, Filter Strip, Detention Basin", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Ohio EPA determined that the WQV precipitation depth of 0.90 inches is the appropriate depth for sizing BMPs", "page_or_section": "1111.4 / page 112" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The invert of the structure must be at least 4 feet above the seasonal high-water table and any impervious layer.", "page_or_section": "1113.6 / page 139" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention Planting Soil Layer: Provide 30 inches of bioretention planting soil.", "page_or_section": "1113.5.3 / page 136" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Limit the maximum depth to 12 inches measured from the final grade of the bioretention cell", "page_or_section": "1113.5.3 / page 135-136" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The WQV is discharged over a 48-hour time frame.", "page_or_section": "1113.3 / page 127" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Provide an outlet structure that fully drains the WQV in 48 hours or more.", "page_or_section": "1113.3.1.1 / page 128" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Use a length to width ratio of at least 3:1 to prevent short-circuiting.", "page_or_section": "1113.4 Retention Basin / page 132" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Use a length to width ratio of 3:1.", "page_or_section": "1113.6.2 Infiltration Basin / page 141" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "Size the wetland to provide storage for the WQV for a time frame of at least 24 hours, above the permanent pool", "page_or_section": "1113.7 / page 142" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum 12\" Ponding Allowed", "page_or_section": "Figure 1113-5 / page 214" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. ODOT Location & Design Manual Volume 2 Drainage Design (July 2022 archive PDF; live manual is web)", "fields_not_found": [] }, "source": { "document_url": "https://dam.assets.ohio.gov/image/upload/transportation.ohio.gov/hydraulic/ld2/archive/2022-07-LD2.pdf", "landing_page_url": "https://www.transportation.ohio.gov/working/publications/location-design-vol-2-jump", "retrieved_at": "2026-08-11T17:21:06.010Z", "original_filename": "oh-odot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": 0.9, "max_drawdown_hours": null, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 3, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:31:22.755Z", "enrich_model": "composer-2.5:run-69327247-bb90-435f-b5e2-1a2f19b43770", "enrich_notes": "WQV sizing uses P=0.90 in with WQV=RV*P*A/12 (RV=0.05+0.9*i). Extended detention sizes WQV+20% sediment allowance; WQV drains ≥48 hr with ≤50% released in first 16 hr. Retention basin EDV (100% WQV) drains ≥24 hr with ≤50% in first 8 hr. Infiltration feasibility requires surface infiltration >0.50 and ≤2.4 in/hr; invert ≥4 ft above seasonal high water table; trench WQV drain ≤48 hr; basin WQV drain ≤24 hr (design equation uses t=24 hr, SF=1.5, k from Table 1113-5). Bioretention: min cell area 5% of impervious tributary area; water table/bedrock ≥1 ft below cell invert; 30 in planting soil plus aggregate layers; underdrain outlet ≥2 ft below final soil surface. Constructed wetland: WQV detained ≥24 hr above permanent pool; dry-weather depth 0.5–2 ft; forebay 7% volume at 3–6 ft depth. Wet extended detention/retention full storage depth typically 3–6 ft. Manufactured systems listed as WQ-only BMP without verification program named.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "oklahoma-odot-ch10", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/oklahoma-odot-ch10/", "data_url": "https://stormwateratlas.com/data/manuals/oklahoma-odot-ch10.json", "document_metadata": { "jurisdiction_name": "Oklahoma Department of Transportation", "jurisdiction_level": "state", "state_code": "OK", "document_title": "ODOT Roadway Drainage Manual, Chapter 10: Stormwater Drainage", "version_or_edition": "November 2014", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 10, 50, 100 ], "water_quality_volume_method": "No statewide water quality volume sizing in Chapter 10; OPDES-regulated systems may require urban BMPs per local ordinances and HEC-22 Chapter 10 guidance when directed by ODOT Environmental Programs Division.", "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [ "HEC-22", "FHWA Hydraulic Toolbox" ], "approved_bmp_categories": [ "Detention Basins", "Storm Drainage Pipe Storage", "Swales and Channels", "Urban BMPs per HEC-22 Chapter 10 (when OPDES or local requirements apply)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "ODOT ROADWAY DRAINAGE MANUAL November 2014 Chapter 10 STORMWATER DRAINAGE", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "ODOT ROADWAY DRAINAGE MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 10 STORMWATER DRAINAGE", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "ODOT Roadway Drainage Manual November 2014", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Chapter 7 \"Hydrology,\" discusses ODOT's practices with respect to hydrology. This section discusses the application of the hydrologic practices specifically to storm drainage systems.", "page_or_section": "Section 10.8.1, Page 10.8-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Freeways and Arterials on grade 10-year ... Freeways and Arterials at sag 50-year ... Local Road - 2 lanes on grade 5-year ... The review flood frequency is typically the 100-year return period.", "page_or_section": "Figure 10.5-A and Section 10.8.3, Pages 10.5-1 and 10.8-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "ODOTs Environmental Programs Division will inform the designer if water quality practices are required, depending on local ordinances and regulations in specific project locations. HEC-22 (2), Chapter 10 provides an introduction to the types of BMPs that have been historically used to provide water quality benefits.", "page_or_section": "Section 10.6.2, Page 10.6-1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Rational Method is the most common method used for the design of storm drains when the peak-flow rate is desired. Its use should be limited to systems with drainage areas of 640 acres or less.", "page_or_section": "Section 10.8.4, Page 10.8-1" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The hydraulic methodology in HEC-22 (2) for the hydraulic analysis and design of a storm drainage system has been adopted.", "page_or_section": "Section 10.13.3, Page 10.13-3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The reduction of peak flows can be achieved by the storage of runoff in detention basins, storm drainage pipes, swales and channels and other detention storage facilities.", "page_or_section": "Section 10.4.9, Page 10.4-4" }, { "field": "practice_mentions.extended_detention", "excerpt": "The reduction of peak flows can be achieved by the storage of runoff in detention basins, storm drainage pipes, swales and channels and other detention storage facilities.", "page_or_section": "10.4.9 Detention Storage, page 18" }, { "field": "practice_mentions.swale", "excerpt": "The reduction of peak flows can be achieved by the storage of runoff in detention basins, storm drainage pipes, swales and channels and other detention storage facilities.", "page_or_section": "10.4.9 Detention Storage, page 18" }, { "field": "enrich_notes", "excerpt": "HEC-22 (2), Chapter 10 provides an introduction to the types of BMPs that have been historically used to provide water quality benefits.", "page_or_section": "10.6.3 Inverted Siphons, page 22" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Chapter 10 is a roadway storm drain design chapter; flood frequencies and Rational/HEC-22 methods are explicit. Water quality BMPs are referenced but not sized in this chapter. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.state_code" ] }, "source": { "document_url": "https://oklahoma.gov/content/dam/ok/en/odot/documents/chapter-10-stormwater-drainage.pdf", "landing_page_url": "https://oklahoma.gov/odot/business-center/pre-construction-design/roadway-design/support-units/oklahoma-roadway-drainage-manual.html", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "oklahoma-odot-ch10.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T09:32:46.689Z", "enrich_model": "composer-2.5:run-edad79f4-6c0a-4d2e-ad0e-40546896452a", "enrich_notes": "Chapter 10 covers storm drain hydrology (Rational Method, max 640 acres), inlet spacing, pipe sizing, and HGL per HEC-22; peak-flow detention may use basins, pipe storage, swales, and channels (Section 10.4.9) with detail in Chapter 12. Water-quality BMP types are referenced via FHWA HEC-22 Chapter 10 only; no WQV depth or SCM sizing parameters appear in the provided excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "or-odot-drainage", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/or-odot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/or-odot-drainage.json", "document_metadata": { "jurisdiction_name": "Oregon", "jurisdiction_level": "state", "state_code": "OR", "document_title": "ODOT Hydraulics Manual Chapter 13", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "ODOT Hydraulics Manual Chapter 13", "page_or_section": "Title / header" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "........................... 13-6 13.7.1 Rational Method ........................................................................", "page_or_section": null } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. ODOT Hydraulics Manual Chapter 13 — Storm Drainage (2014) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.oregon.gov/odot/hydraulics/Docs_Hydraulics_Manual/Hydraulics-13.pdf", "landing_page_url": "https://www.oregon.gov/odot/hydraulics/pages/hydraulics-manual.aspx", "retrieved_at": "2026-08-11T17:59:10.587Z", "original_filename": "or-odot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T09:33:51.145Z", "enrich_model": "composer-2.5:run-2069e564-2888-49c8-898e-a13c82ab5687", "enrich_notes": "ODOT Hydraulics Manual Chapter 13 (April 2014) addresses highway storm drainage: pavement drainage, inlets, storm drains, drywells (Ch. 14), energy dissipators. Hydrology via rational method (≤200 acres). No water-quality volume, SCM/BMP sizing, or canonical LID practice design criteria in supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "new-orleans-jefferson-la", "processed_at": "2026-08-17T03:19:55.618Z", "detail_url": "https://stormwateratlas.com/new-orleans-jefferson-la/", "data_url": "https://stormwateratlas.com/data/manuals/new-orleans-jefferson-la.json", "document_metadata": { "jurisdiction_name": "Orleans and Jefferson Parishes", "jurisdiction_level": "county", "state_code": "LA", "document_title": "Stormwater BMP Guidance Tool: A Stormwater Best Management Practices Guide for Orleans and Jefferson Parishes", "version_or_edition": "October 2010", "adoption_or_effective_date": "2010-10", "last_revised_date": "2010-10", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "No single parish-wide water quality volume is mandated. Guidance notes other cities require first-inch rainfall capture or matching pre-construction runoff volume, but recommends a minimum volume-reduction goal of matching average annual predevelopment evapotranspiration for Orleans/Jefferson redevelopment constraints. BMP sizing uses a water quality design volume; design storm depth can be back-calculated from that volume (d = V × 12 / [C × A × 43560], C = 0.05 + 0.9 × imp). Performance is evaluated via percent volume capture, with continuous simulation (e.g., EPA SWMM) preferred for accurate estimates.", "peak_flow_calculation_method": [ "Rational Method", "Unit hydrograph methods", "SCS curve number method", "SCS Type III dimensionless hyetograph (New Orleans area)", "Continuous simulation (SWMM, HSPF)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Site Design BMPs", "Biofiltration BMPs (Rain Gardens/Bioretention, Vegetated Swale Filter, Vegetated Filter Strip)", "Permeable Pavement and Media Filtration BMPs (Porous Asphalt/Concrete/Pavers, Gravel Trenches, Sand Filters)", "Building BMPs (Cistern/Rain Barrel, Planter Box, Green Roof)", "Retention and Detention BMPs (Constructed Treatment Wetland, Wet Retention Basin, Dry Extended Detention Basin)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "A Stormwater Best Management Practices Guide for Orleans and Jefferson Parishes", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Guide for Orleans and Jefferson Parishes", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater BMP Guidance Tool A Stormwater Best Management Practices Guide for Orleans and Jefferson Parishes", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "--- page 135 --- Appendix A A-1 October 2010 APPENDIX A Stakeholder Survey Response Summary 1 INTRODUCTION An online survey was created to help guide the development of this document. The goal of the survey was to identify stakeholder’s priorities regarding stormwater man", "page_or_section": "p. 135" }, { "field": "practice_mentions.swale", "excerpt": "Answer Answer Description A Vegetated swales", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.bioretention", "excerpt": "F Bioretention G Rain gardens", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "C Permeable pavement", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.sand_filter", "excerpt": "K Sand filters", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.extended_detention", "excerpt": "L Extended detention basins", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "M Infiltration Basins", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.wet_pond", "excerpt": "N Retention basins/wet ponds", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "I Pocket wetlands", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "J Hydrodynamic separators", "page_or_section": "Appendix A Table A-2, page 138" }, { "field": "fields_not_found.shwt_separation_inches", "excerpt": "water table elevations", "page_or_section": "Appendix A §1.5 / Table A-3, page 139" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Guidance tool for two parishes (county-level), not a binding design ordinance. No uniform WQv; cites City of New Orleans 10-year/24-hour and Jefferson Parish 10-year peak-match as local examples. SWMM/HSPF are evaluation tools, not required software. Pipeline excerpt repair removed 13 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.relationship_to_state_manual", "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.landcan.org/pdfs/Bayou_Land_Guidance_NO_BMP.176113438.pdf", "landing_page_url": "https://deq.louisiana.gov/page/storm-water-protection", "retrieved_at": "2026-08-08T10:20:00.000Z", "original_filename": "new-orleans-jefferson-la.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:22:20.501Z", "enrich_model": "composer-2.5:run-573df926-de20-41e1-b9fb-5cdbcc04ed1e", "enrich_notes": "Provided corpus is Appendix A stakeholder survey only (pages 135–142); no BMP design numeric criteria. Atlas notes no parish-wide WQv depth and volume-based sizing elsewhere in the manual—not in these excerpts. Survey cites water table as a top implementation constraint but gives no SHWT separation distance.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pa-bmp-2006", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pa-bmp-2006/", "data_url": "https://stormwateratlas.com/data/manuals/pa-bmp-2006.json", "document_metadata": { "jurisdiction_name": "Pennsylvania", "jurisdiction_level": "state", "state_code": "PA", "document_title": "Pennsylvania Stormwater Best Management Practices Manual", "version_or_edition": "363-0300-002 / December 30, 2006", "adoption_or_effective_date": "2006-12-30", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 100 ], "water_quality_volume_method": "Volume Control Guideline 1 (CG-1): do not increase post-development total runoff volume for storms ≤ 2-year/24-hour. Volume Control Guideline 2 (CG-2, sites ≤1 ac without storage facilities): capture first 2 inches from new impervious; permanently remove first 1.0 inch (reuse, evaporation, transpiration, infiltration), with at least 0.5 inch infiltrated where possible. Water quality performance goal: 85% reduction in TSS and total phosphorus loads and 50% reduction in NO3-N solute loads vs. post-development land use.", "peak_flow_calculation_method": [ "Rational Method", "SCS (NRCS) Unit Hydrograph Method", "Runoff Curve Number Method", "Small Storm Hydrology Method" ], "required_hydrologic_hydraulic_software": [ "WIN TR-20", "WIN TR-55", "Storm Water Management Model (SWMM)" ], "approved_bmp_categories": [ "Non-Structural Site Design BMPs", "Pervious Pavement with Infiltration Bed", "Infiltration Basin", "Subsurface Infiltration Bed", "Infiltration Trench", "Rain Garden / Bioretention", "Dry Well / Seepage Pit", "Constructed Filter", "Vegetated Swale", "Vegetated Filter Strip", "Infiltration Berm & Retentive Grading", "Vegetated Roof", "Runoff Capture & Reuse", "Constructed Wetland", "Wet Pond / Retention Basin", "Dry Extended Detention Basin", "Water Quality Filters & Hydrodynamic Devices", "Riparian Buffer Restoration", "Landscape Restoration", "Floodplain Restoration", "Level Spreader" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "TITLE: Pennsylvania Stormwater Best Management Practices Manual", "page_or_section": "Page i" }, { "field": "document_metadata.version_or_edition", "excerpt": "363-0300-002 / December 30, 2006", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE DATE: December 30, 2006", "page_or_section": "Page i" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Do not increase the post-development total runoff volume for all storms equal to or less than the 2-year/24-hour event.", "page_or_section": "Chapter 3, Section 3.3.3 Volume Control Guideline 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Do not increase the peak rate of discharge for the 1-year through 100-year events (at minimum)", "page_or_section": "Chapter 3, Section 3.4 Peak Rate Control Guideline" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Stormwater facilities shall be sized to capture at least the first two inches (2\") of runoff from all contributing impervious surfaces. At least the first one inch (1.0\") of runoff from new impervious surfaces shall be permanently removed from the runoff flow", "page_or_section": "Chapter 3, Section 3.3.4 Volume Control Guideline 2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Achieve an 85 percent reduction in post-development particulate associated pollutant load (as represented by Total Suspended Solids), an 85 percent reduction in post-development total phosphorus loads, and a 50 percent reduction in post-development solute loads (as represented by NO3-N)", "page_or_section": "Chapter 3, Section 3.5 Water Quality Control Guideline" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "8.3.1 The Rational Method ... 8.3.2 SCS (NRCS) Unit Hydrograph Method", "page_or_section": "Chapter 8 Table of Contents" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "8.4.2 SCS/NRCS Models: WIN TR-20 and WIN TR-55 ... 8.4.4 Storm Water Management Model (SWMM)", "page_or_section": "Chapter 8 Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "6.4 Volume/Peak Rate Reduction by Infiltration BMPs ... 6.5 Volume/Peak Rate Reduction BMPs ... 6.6 Runoff Quality/Peak Rate BMPs", "page_or_section": "Chapter 6 Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "PRV (ft3) = Total Impervious Area (ft2) x 1 inch x 1/12", "page_or_section": "Chapter 8, Worksheet 7, page 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "2 Inch Runoff - Multiply Total Impervious Area by 2 inch", "page_or_section": "Chapter 8, Worksheet 7, page 37" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Surface Ponding depth should not exceed 6 inches in most cases and should empty within 72 hours.", "page_or_section": "BMP 6.4.5 Rain Garden / Bioretention, Design Considerations, page 57" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Allow 2 ft buffer between bed bottom and seasonal high groundwater table and 2 ft buffer for rock.", "page_or_section": "BMP 6.4.2 Infiltration Basin, Key Design Elements, page 27" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "It is desirable to maintain a 2-foot clearance above regularly occurring seasonally high water table.", "page_or_section": "Appendix C Protocol 2, Site Conditions, page 14" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting soil depth should generally be at least 18\" where only herbaceous plant species will be utilized.", "page_or_section": "BMP 6.4.5 Rain Garden / Bioretention, page 57" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Surface Ponding depth should not exceed 6 inches in most cases", "page_or_section": "BMP 6.4.5 Rain Garden / Bioretention, page 57" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration BMPs must have an infiltration of at least 0.5 in/hr.", "page_or_section": "Chapter 8, Worksheet 6, page 35" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "bioretention areas are not to be confused with constructed wetlands or wet ponds which permanently pond water. Bioretention is best suited for areas with at least moderate infiltration rates (more than 0.1 inches per hour).", "page_or_section": "BMP 6.4.5, page 57" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "A minimum length-to-width ratio of 2:1 is recommended to maximize sedimentation.", "page_or_section": "BMP 6.6.3 Dry Extended Detention Basin, Basin Sizing, page 176" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "PA DEP technical guidance 363-0300-002 (Dec 2006). Superseded in intent by the PCSM Manual (pa-state) but still cited by municipalities and Act 167 ordinances. PDF from Wrightstown municipal mirror; official eLibrary folder docId 7876 blocks automated PDFProvider fetch.", "fields_not_found": [ "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.wrightstownpa.org/media/1993/pennsylvania_stormwater_best_management_practices_manual.pdf", "landing_page_url": "https://greenport.pa.gov/elibrary/GetFolder?FolderID=1368916", "retrieved_at": "2026-08-12T22:49:00.790Z", "original_filename": "tmp-pa-bmp-2006.json" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:37:03.451Z", "enrich_model": "composer-2.5:run-ccc34f31-31b0-490b-9c77-ab30ae7a2f86", "enrich_notes": "PA DEP 363-0300-002 (2006): CG-2 worksheets size 2 in capture from impervious and 1 in depths for PRV/EDV; infiltration BMPs need ≥0.5 in/hr for small-site peak-rate exemption; Protocol 2 requires 2 ft (24 in) clearance to seasonally high water table and bedrock; bioretention ponding ≤6 in and drawdown within 72 h with ≥18 in planting soil; extended detention basins recommend minimum L:W 2:1; acceptable underlying soil infiltration discussed as 0.1–10 in/hr in Protocol 2.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pa-state", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pa-state/", "data_url": "https://stormwateratlas.com/data/manuals/pa-state.json", "document_metadata": { "jurisdiction_name": "Pennsylvania", "jurisdiction_level": "state", "state_code": "PA", "document_title": "Pennsylvania Post-Construction Stormwater Management (PCSM) Manual", "version_or_edition": "January 28, 2023 / DRAFT", "adoption_or_effective_date": null, "last_revised_date": "2023-01-28", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 50, 100 ], "water_quality_volume_method": "A pollutant load approach, coupling volume and water quality management, in which statistically derived land cover-based pollutant concentrations are applied to runoff, volume reductions through SCMs are taken into account, and post-construction pollutant loads are compared to pre-construction pollutant loads.", "peak_flow_calculation_method": [ "NRCS hydrologic soil-cover complex method", "Green and Ampt equation", "Snyder Unit Hydrograph", "WINSLAMM small storm hydrology method", "nonlinear reservoir runoff", "kinematic wave methods" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS", "iRIC", "EPA SWMM" ], "approved_bmp_categories": [ "Protect and Preserve Natural Landscape Processes", "Enhanced Natural Landscape SCMs", "Infiltration-Based SCMs", "Non-Infiltration SCMs", "Managed Release Concept", "Rate Control SCMs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "TITLE: Pennsylvania Post-Construction Stormwater Management (PCSM) Manual", "page_or_section": "Page i" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "DEPARTMENT OF ENVIRONMENTAL PROTECTION\nBureau of Clean Water", "page_or_section": "Page i" }, { "field": "document_metadata.state_code", "excerpt": "System. CWA – Clean Water Act. DEP – Pennsylvania Department of Environmental Protection. E&S – Erosion and Sediment Control.", "page_or_section": "p. 715" }, { "field": "document_metadata.document_title", "excerpt": "TITLE: Pennsylvania Post-Construction Stormwater Management (PCSM) Manual", "page_or_section": "Page i" }, { "field": "document_metadata.version_or_edition", "excerpt": "386-0300-001 / January 28, 2023 / DRAFT", "page_or_section": "Page i" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE DATE: Upon publication of notice as final in the Pennsylvania Bulletin.", "page_or_section": "Page i" }, { "field": "document_metadata.last_revised_date", "excerpt": "386-0300-001 / January 28, 2023 / DRAFT", "page_or_section": "Page i" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Pennsylvania Post-Construction Stormwater Management Manual (PCSM Manual or Manual) was developed to update and replace the Pennsylvania Stormwater Best Management Practices Manual (363-0300-002) that was published by the Pennsylvania Department of Environmental Protection (DEP) in December 2006", "page_or_section": "Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "manage the net change in peak rate for the 2-, 10-, 50-, and 100-year/24-hour storm events in a manner not to exceed preconstruction rates", "page_or_section": "Page 2-37" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water quality is addressed in this Manual through a pollutant load approach, coupling volume and WQM. First, statistically derived land cover-based pollutant concentrations are applied to runoff from existing and proposed site conditions. Second, volume reductions through SCMs are taken into account. Finally, post-construction pollutant loads are evaluated based on SCM effluent (outflow) pollutant concentration data from accepted data sources such as the National Stormwater Quality Database and the International Stormwater BMP Database, and compared to pre-construction pollutant loads.", "page_or_section": "Page 1-18" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Methods include the NRCS hydrologic soil-cover complex method, Green and Ampt equation, Snyder Unit Hydrograph, and WINSLAMM small storm hydrology method.", "page_or_section": "Page 2-53" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HEC-RAS, International River Interface Cooperative (iRIC), or other software capable of performing a sediment transport analysis.", "page_or_section": "Page 2-65" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "A.1 Protect and Preserve Natural Landscape Processes\nA.2 Enhanced Natural Landscape SCMs\nB.1 Infiltration-Based SCMs\nB.2 Non-Infiltration SCMs\nManaged Release Concept\nRate Control SCMs", "page_or_section": "Page 3-4, Table 3-1" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Permanent pool volume should hold the runoff generated by 1.2-inch/2-hour rainfall over the contributing drainage area.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Drawdown time to native soil surface (i.e., bottom of storage) is limited to 72 hours.", "page_or_section": "Page 3-135 / Section 3.5.4 Infiltration Trench" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A minimum two-foot separation distance from an infiltration SCM bottom to a limiting zone, including the SHWT, is generally necessary.", "page_or_section": "Appendix B.8 / Page B-31" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Table 3-90 ... 3.6.1 Bioretention ... Soil Media Depth Min. 18 in", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Table 3-90 ... 3.6.1 Bioretention ... Maximum Ponding/Storage Depth ... 2 ft", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Table 3-90 ... 3.5.3 Permeable Pavement ... Maximum Ponding/Storage Depth ... 3 ft (Min. 18 in)", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Permanent pool should be a minimum of five feet deep.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Table 3-90 ... 3.8.2 Naturalized Detention Basin ... Maximum Ponding Time ... 72 hrs", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The length to width ratio of the basin should be a minimum of 2:1 to avoid short circuiting.", "page_or_section": "Page 3-286 / Section 3.8.1 Wet Basin" }, { "field": "design_parameters.green_roof_media_depth_inches", "excerpt": "Table 3-90 ... 3.6.2 Green Roof ... Soil Media Depth Min. 3 in", "page_or_section": "Page 3-310 / Table 3-90" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom widths range from two feet to eight feet.", "page_or_section": "Page 3-96 / Vegetated Conveyance SCM (range only)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "The document is a state-level Draft PCSM Manual for Pennsylvania. The effective date is conditional upon publication as final in the Pennsylvania Bulletin, hence the date is set to null.", "fields_not_found": [] }, "source": { "document_url": "https://franklinccd.org/wp-content/uploads/PENNSYLVANIA_POST-CONSTRUCTION_STORMWATER_MANAGEMENT_PCSM_MANUAL.pdf", "landing_page_url": "https://www.pa.gov/agencies/dep/programs-and-services/water/clean-water/stormwater-management/construction-stormwater/eands-resources", "retrieved_at": "2026-08-07T10:59:18.082Z", "original_filename": "pa-pcsm-manual.pdf" }, "design_parameters": { "wqv_depth_inches": 1.2, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": 24, "permeable_pavement_storage_depth_inches": 18, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 60, "ed_drain_time_hours": 72, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": 3, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:38:43.564Z", "enrich_model": "composer-2.5:run-cff1470d-4137-4eb3-9d11-ddca194b43ac", "enrich_notes": "PA PCSM uses a pollutant-load WQM approach with frequent 1.2-inch/2-hour design rainfall references. Infiltration suitability thresholds are 0.25 and 0.4 in/hr (not a single design infiltration rate). General SHWT separation is 2 ft (24 in) for infiltration SCMs; MRC bioretention prefers 2 ft between SHWT and bottom of soil media. Drawdown/ponding time limits vary by SCM (48–96 hr in Table 3-90); 72 hr drawdown to native soil is stated for infiltration trench and underground infiltration. Vegetated conveyance bottom width is 2–8 ft (no single design width). MTDs are referenced without a named verification program.", "enrich_schema_version": 2, "fields_not_found": [ "design_infiltration_rate_in_per_hr", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pa-penndot-drainage", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pa-penndot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/pa-penndot-drainage.json", "document_metadata": { "jurisdiction_name": "Pennsylvania Department of Transportation (PennDOT)", "jurisdiction_level": "state", "state_code": "PA", "document_title": "PennDOT Drainage Manual (Publication 584)", "version_or_edition": "March 2015 Edition, Change No. 1 (June 2022)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "HEC-HMS" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS" ], "approved_bmp_categories": [ "Bioretention", "Infiltration Trench", "Wet Pond", "Dry Pond", "Extended Detention", "Vegetated Swale", "Filter Strip", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Pennsylvania Department of Transportation (PennDOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "PennDOT Drainage Manual (Publication 584)", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "............. 7A - 6 7A.7(a) Composite 10-year storm in Region 5 (Metric). ...................................................", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "............................. 7 - 16 I. Rational Method ........................................................................", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Infiltration Trench, Wet Pond, Dry Pond", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The outlet structure should be designed to convey the appropriate design flow and dewater the basin completely within 48 hours after the end of each event.", "page_or_section": "Chapter 14, §14.15 / page 799" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The outlet structure should be designed to convey the appropriate design flow and dewater the basin completely within 48 hours after the end of each event.", "page_or_section": "Chapter 14, §14.15 / page 799" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min. 24 in. between bottom and bedrock/seasonal high groundwater table if designed as infiltration system", "page_or_section": "Figure 14.2 Vegetated Swale Summary / page 760" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Under the vegetated surface layer is approximately 24 in. of permeable soil (minimum 0.5 in/hr infiltration rate) containing a high level of organic matter.", "page_or_section": "Chapter 14, Vegetated Swale / page 760" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum flow length to width ratio is 2:1.", "page_or_section": "Chapter 12, Sediment Basin / page 658" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width 2-8 ft", "page_or_section": "Figure 14.2 Vegetated Swale Summary / page 760" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Min. 24 in. between bottom and bedrock/seasonal high GWT", "page_or_section": "Figure 14.9 Infiltration Berm Summary / page 765" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "A reduction of 25 m3 (350 ft3) per total contributing hectare (acre) may be utilized for basins with length to width ratios of 4:1 or greater.", "page_or_section": "Chapter 12, Sediment Basin / page 658" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. PennDOT Drainage Manual Pub 584 (March 2015 Edition, Change No. 1 June 2022)", "fields_not_found": [ "design_criteria.water_quality_volume_method" ] }, "source": { "document_url": "https://www.pa.gov/content/dam/copapwp-pagov/en/penndot/documents/public/pubsforms/publications/pub-584/june%202022-change%201.pdf", "landing_page_url": "https://www.pa.gov/agencies/penndot/programs-and-doing-business/environment/hydrology-and-hydraulics", "retrieved_at": "2026-08-11T17:21:05.997Z", "original_filename": "pa-penndot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:37:53.875Z", "enrich_model": "composer-2.5:run-b4d29efd-c873-49ac-8593-f8765cbca79d", "enrich_notes": "PennDOT Pub 584 Ch.14 gives SCM summary sheets; Ch.12 sediment basins use 2:1 min L:W and 4–7 day dewatering (days, not WQV depth). Wet pond permanent pool sized as 3×WQV (volume, no inch depth in excerpts). SHWT/limiting zone often cited as 24 in or 2 ft from infiltration interface. BUD allows max 72 hr drawdown separately from general 48 hr outlet dewatering.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "philadelphia-pa", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/philadelphia-pa/", "data_url": "https://stormwateratlas.com/data/manuals/philadelphia-pa.json", "document_metadata": { "jurisdiction_name": "Philadelphia", "jurisdiction_level": "municipality", "state_code": "PA", "document_title": "Philadelphia Stormwater Management Guidance Manual", "version_or_edition": "Version 3.4", "adoption_or_effective_date": "2026-07", "last_revised_date": "2026-07", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Infiltration of the first 1.5 inches of runoff from all directly connected impervious areas (DCIA) within the limits of earth disturbance.", "peak_flow_calculation_method": [ "NRCS Curve Number Method", "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioinfiltration/Bioretention", "Porous Surfaces", "Green Roofs", "Subsurface Infiltration", "Cisterns", "Blue Roofs", "Ponds and Wet Basins", "Subsurface Detention", "Media Filters", "Blue-Green Roofs", "Drainage Wells" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The Philadelphia Stormwater Management Guidance Manual (the Manual, or SMGM) is a comprehensive resource for the development community in complying with the Philadelphia Water Department (PWD) Stormwater Regulations", "page_or_section": "Introduction, Page 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The City of Philadelphia is required, by a series of State and Federal regulations and mandates, to clean up its waterways.", "page_or_section": "Introduction, Page 10" }, { "field": "document_metadata.state_code", "excerpt": "Professional Engineer licensed in the Commonwealth of Pennsylvania", "page_or_section": "Chapter 2, Page 23" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Guidance Manual", "page_or_section": "Cover Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "alterations including the conversion of pervious areas to impervious cover without authorization from PWD. It does not require the property owner to construct the SMPs if the development project associated with the SMPs does not commence or if no earth disturbance take", "page_or_section": "p. 76" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Philadelphia Stormwater Management Guidance Manual (the Manual, or SMGM) is a comprehensive resource for the development community in complying with the Philadelphia Water Department (PWD) Stormwater Regulations (Stormwater Regulations) and designing stormwater management on private property.", "page_or_section": "Introduction, Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Return period DURATION 1 yr 2 yr 5 yr 10 yr 25 yr 50 yr 100 yr", "page_or_section": "Chapter 3, Page 100, Table 3.4-3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Water Quality requirement stipulates infiltration of the first 1.5 inches of runoff from all directly connected impervious areas (DCIA) within the limits of earth disturbance. This quantity of stormwater runoff is referred to as the Water Quality Volume (WQv).", "page_or_section": "Chapter 1, Page 15" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The NRCS Curve Number Method is used to estimate site stormwater runoff from a given storm. ... The Rational Method may be used when designing storm sewers.", "page_or_section": "Chapter 3, Page 98 & Page 95" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "This chapter consists of guidance and requirements for the following SMPs: Section 4.1 – Bioinfiltration/Bioretention Section 4.2 – Porous Surfaces Section 4.3 – Green Roofs Section 4.4 – Subsurface Infiltration Section 4.5 – Cisterns Section 4.6 – Blue Roofs Section 4.7 – Ponds and Wet Basins Section 4.8 – Subsurface Detention Section 4.9 – Media Filters Section 4.14 – Blue-Green Roofs Section 4.15 – Drainage Wells", "page_or_section": "Chapter 4, Section 4.0.2, Page 2" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The Water Quality requirement stipulates infiltration of the first 1.5 inches of runoff from all directly connected impervious areas (DCIA)", "page_or_section": "Section 1.2.1 / page 37" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "R = 1.5 inches runoff depth", "page_or_section": "Chapter 3 Step 4 / page 210" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The maximum allowable drain down time is 72 hours after the 24-hour storm event.", "page_or_section": "Section 4.1.3 General design standards / page 263" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Design the SMP(s) to ensure drain down time is no more than 72 hours based on the tested infiltration rate", "page_or_section": "Chapter 3 Step 5a / page 210" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A two-foot separation between the infiltration interface (SMP bottom elevation) and the regularly occurring seasonally high-water table must be maintained.", "page_or_section": "Section 3.3 Step 3 / page 206" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The SMP must be located at least two feet above any poorly infiltrating soils, seasonal high groundwater table, bedrock, or any other limiting zone.", "page_or_section": "Section 4.1.3 item 6b / page 263" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The planting soil medium must have a minimum depth of two feet.", "page_or_section": "Section 4.1.3 item 21 / page 265" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The minimum allowable ponding depth below the lowest outlet device is three inches.", "page_or_section": "Section 4.1.3 item 11 / page 264" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://water.phila.gov/wp-content/uploads/files/stormwater-management-guidance-manual.pdf", "landing_page_url": "https://water.phila.gov/development/stormwater-plan-review/manual/", "retrieved_at": "2026-08-07T11:00:41.804Z", "original_filename": "philadelphia-smgm.pdf" }, "design_parameters": { "wqv_depth_inches": 1.5, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 3, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:44:08.041Z", "enrich_model": "composer-2.5:run-bf9911e3-ad1a-481c-b671-96f52a62bf2a", "enrich_notes": "WQv is 1.5 in over DCIA; dynamic bioinfiltration may use 1 in static storage if routing shows full 1.5 in managed. Media filters use 2 in/hr for sand/soil surface-area sizing and min 18 in filter media depth (distinct from 24 in bioretention planting soil). Soils >10 in/hr require amendments. DCIA:footprint loading max 16:1 bioinfiltration/bioretention, 10:1 subsurface infiltration. Glossary lists TAPE, NJCAT, TARP but excerpts do not tie them to MTD approval.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tucson-az-detention", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tucson-az-detention/", "data_url": "https://stormwateratlas.com/data/manuals/tucson-az-detention.json", "document_metadata": { "jurisdiction_name": "Pima County", "jurisdiction_level": "county", "state_code": "AZ", "document_title": "Design Standards for Stormwater Detention and Retention", "version_or_edition": "First Edition June 2014; Chapter 6 revised February 2015", "adoption_or_effective_date": "2014-06", "last_revised_date": "2015-02", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "First-flush retention: capture and retain runoff from 0.5 inch of rainfall on newly disturbed or impervious areas (85th percentile storm). Required volumes by land type from SCS Curve Number method (e.g., 1440 ft³/ac impervious on lower-permeability areas; 1815 ft³/ac on mapped riparian/higher-permeability areas).", "peak_flow_calculation_method": [ "PC-Hydro", "Pima County Technical Policy TECH-015 (Acceptable Methods for Determining Peak Discharges)", "Pima County Technical Policy TECH-018 (Acceptable Model Parameterization)", "City of Tucson Standards Manual for Drainage Design and Floodplain Management (where applicable)", "HEC-HMS (basin routing)" ], "required_hydrologic_hydraulic_software": [ "PC-Hydro", "PC-LID spreadsheet", "HEC-HMS (Version 3.3 or higher acceptable for basin routing)" ], "approved_bmp_categories": [ "Detention Basins", "Stormwater Harvesting Basins", "Roadside Stormwater Harvesting Basins", "Bioretention Basins", "Retention within Detention Basins", "Pervious Pavements (porous gravel, concrete grid, PICP, pervious concrete)", "Dry Wells", "Low Impact Development (LID) Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Pima County Regional Flood Control District", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "runoff detention and retention systems are required for development in Pima County... management regulations throughout the jurisdictions of Pima County", "page_or_section": "Section 1.1" }, { "field": "document_metadata.state_code", "excerpt": "Design and Floodplain Management in Tucson, Arizona; or c. Other methods accepted by the Floodplain Administrator. 2. When flow crosses a sidewalk or other paved pedestrian pathway, a scupper or other conveyance to prohibit overtopping of the 10-year design discharge shall be", "page_or_section": "pp. 44–45" }, { "field": "document_metadata.document_title", "excerpt": "Design Standards for Stormwater Detention and Retention", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "First Edition June 2014... Chapter 6 Revised to Include Benefits of Multiple-Use Basins February 2015", "page_or_section": "Revisions" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "First Edition June 2014", "page_or_section": "Revisions / Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "Chapter 6 Revised to Include Benefits of Multiple-Use Basins February 2015", "page_or_section": "Revisions" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Supplement to Title 16, Chapter 16.48, Runoff Detention Systems Floodplain and Erosion Hazard Management Ordinance", "page_or_section": "Cover" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "New development located within a Balanced Basin must provide sufficient detention to reduce the post-developed 2-, 10- and 100-year peak discharge rates to the pre-developed rates.", "page_or_section": "Section 1.2" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "New development located within a Critical Basin must provide sufficient detention to reduce the post-developed 2-, 10- and 100-year peak discharge rates to 90% of the pre-developed peak discharge rates.", "page_or_section": "Section 1.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "First-flush retention is defined as the capturing and retaining of the stormwater runoff volume from 0.5 inch of rainfall on all newly disturbed or impervious areas for new development or redevelopment", "page_or_section": "Section 1.5, Page 5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The first-flush runoff volume is the volume of stormwater runoff from 0.5 inch of rainfall that is expected to discharge from impervious and disturbed areas. The 0.5-inch rainfall event is the 85th percentile storm event", "page_or_section": "Section 2.1, Page 8" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The first-flush runoff volumes required for retention by this Section were determined using the Soil Conservation Service (SCS) Curve Number method with a 0.5-inch rainfall event (Table 2.1).", "page_or_section": "Section 2.2, Page 9" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The pre-developed conditions peak discharge rates for each return period shall be established using the modeling methods described in the District's Technical Policy, TECH-015, Acceptable Methods for Determining Peak Discharges, and Technical Policy, TECH-018", "page_or_section": "Section 3.2.1, Page 21" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The solution to Equation 3.1 is the runoff volume reported in the PC-Hydro hydrograph report.", "page_or_section": "Section 3.3" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "HEC-HMS is also acceptable software for basin routing.", "page_or_section": "Section 3.4" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Volumes of each basin were calculated using the PC-LID spreadsheet.", "page_or_section": "Section 2.2 Example, Page 12" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "PC-Hydro – A semi-empirical rainfall-runoff model accepted in Pima County for predicting flood peaks", "page_or_section": "Glossary" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "HEC-HMS Version 3.3, or higher, with supporting documentation", "page_or_section": "Documentation requirements" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Design Standards for Stormwater Detention and Retention for Pima County 53 6. To allow for inspection and maintenance, LID practices shall be legally and physically accessible. 7. Upon completion of construction of all LID practices, an As-built Certification s", "page_or_section": "p. 65" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "This manual introduces the use of Low Impact Development (LID) practices.", "page_or_section": "Section 1.5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "First-flush retention is defined as the capturing and retaining of the stormwater runoff volume from 0.5 inch of rainfall on all newly disturbed or impervious areas", "page_or_section": "Section 1.5 / page 17" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first-flush runoff volume is the volume of stormwater runoff from 0.5 inch of rainfall that is expected to discharge from impervious and disturbed areas. The 0.5-inch rainfall event is the 85th percentile storm event", "page_or_section": "Section 2.1 / page 20" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The constructed soil medium shall be 16 inches to 36 inches deep.", "page_or_section": "Section 5.7 Bioretention Basin / page 71" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "The bioretention basin shall have a flat-topped surface that is depressed a minimum of 6 inches and a maximum of 12 inches below adjacent finished grade.", "page_or_section": "Section 5.7 / page 71" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Used by City of Tucson for detention/retention design; jurisdiction is Pima County Regional Flood Control District standards adopted for Tucson engineering code practice.", "fields_not_found": [] }, "source": { "document_url": "https://www.tucsonaz.gov/files/sharedassets/public/v/1/pdsd/documents/engineering-code/updated-retention-detention-manual.pdf", "landing_page_url": "https://www.tucsonaz.gov/Departments/Planning-Development-Services/Codes/Engineering-Codes", "retrieved_at": "2026-08-08T11:41:45.970Z", "original_filename": "updated-retention-detention-manual.pdf" }, "design_parameters": { "wqv_depth_inches": 0.5, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 16, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:24:21.869Z", "enrich_model": "composer-2.5:run-f8027483-f701-467d-bf91-85a9864fef99", "enrich_notes": "First-flush retention uses 0.5-inch rainfall (85th percentile); Table 2.1 gives retention volumes (e.g., 1440 ft³/ac impervious lower-permeability, 1815 ft³/ac riparian). Bioretention surface depression is 6–12 inches below grade (min and max both stated). Bioretention gravel subbase 6–24 inches; engineered medium void space assumed 30%. Stormwater/roadside/non-contributing harvesting basins: max storage depth 9 inches, min freeboard 3 inches. Retention within detention basins: max 9 inches below lowest outlet. Dry wells: design percolation Pd=Pr/Dr (in/hr), 10-ft minimum from water table/impermeable layer to injection screen base; not a single fixed infiltration rate. Pervious pavement analyzed as disturbed, not impervious; no section storage depth in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "pinellas-county-fl", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/pinellas-county-fl/", "data_url": "https://stormwateratlas.com/data/manuals/pinellas-county-fl.json", "document_metadata": { "jurisdiction_name": "Pinellas County", "jurisdiction_level": "county", "state_code": "FL", "document_title": "Stormwater Manual", "version_or_edition": "Revised April 23, 2024", "adoption_or_effective_date": "2024-04-23", "last_revised_date": "2024-04-23", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Presumptive treatment criteria include 0.5 inch for dry retention and 1 inch for wet detention over the contributing area (small-site provisions). Manual Parts A–B cover water quality/quantity performance standards, BMP criteria (bioswales, wet detention, green infrastructure), and attenuation/storage requirements.", "peak_flow_calculation_method": [ "Water quantity attenuation and storage criteria (Chapters 1–2)", "Off-site compensating treatment / regional facilities", "BMP-specific hydraulic design (Part B)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Dry retention / exfiltration", "Wet detention", "Bioswales / treatment swales / green gutters", "Green infrastructure BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "PINELLAS COUNTY", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Pinellas County", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "REVISED APRIL 23, 2024", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "APRIL 23, 2024", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "APRIL 23, 2024", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Pinellas County Stormwater Manual / state water quality standards", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Presumptive treatment criteria of 0.5\" for dry retention and 1\" for wet detention", "page_or_section": "Small sites" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "attenuation, storage and treatment required", "page_or_section": "Performance standards" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioswales/Treatment Swales / Wet Detention / Green Infrastructure", "page_or_section": "Chapter 4 / 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Presumptive water quality criteria of 0.5\" for dry ponds and 1\" for wet ponds over the entire parcel area are provided", "page_or_section": "1.5.3.1 Administrative Adjustments, page 13" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The retention basin must recover the required treatment volume of stormwater within 72 hours, with a safety factor of two", "page_or_section": "4.1.4 Design Criteria, page 47" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "All retention systems must provide the capacity for the RTV of stormwater to recover to the bottom of the system within 72 hours following a storm event", "page_or_section": "Appendix A.1.3, page 220" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high ground water table will be at least two feet beneath the bottom of the retention basin", "page_or_section": "4.1.4 Design Criteria, page 47" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "REQUIRED MIN. DISTANCE OF 12\" FROM BOTTOM OF RAIN GARDEN TO SEASONAL HIGH GROUNDWATER TABLE (SHGWT)", "page_or_section": "Figure 4.13.1 Rain Garden, page 149" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "stormwater must pass through at least two inches of topsoil, an appropriate depth of planting soil, and a minimum of 12 inches of filter media with a carbon source (BAM)", "page_or_section": "4.12 Biofiltration Systems, page 133" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "The minimum infiltration rate through the vegetation and soil will be at least one inch per hour", "page_or_section": "4.4 Treatment Swales, page 68" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "maximum allowable final design rate not to exceed 1.5 feet/hour (18 inches per hour)", "page_or_section": "1.5.5.12 Soil Investigation / Design, page 21" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "It is recommended that the bottom of the swale be at least two feet wide to facilitate mowing", "page_or_section": "4.4 Treatment Swales, page 68" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pinellas County Stormwater Manual Apr 2024. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://pinellas.gov/wp-content/uploads/2021/11/Stormwater_Manual.pdf", "landing_page_url": "https://pinellas.gov/", "retrieved_at": "2026-08-10T08:41:07.399Z", "original_filename": "pinellas-county-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 12, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:47:14.934Z", "enrich_model": "composer-2.5:run-16062873-4e52-451a-8349-0fab357965bf", "enrich_notes": "Presumptive WQv: 0.5 inch over parcel for dry ponds/retention and 1 inch for wet ponds (small/large site GI credit, page 13). SHGWT separation varies: 24 in (2 ft) retention basin/swale (pages 45, 47, 68); 12 in rain garden and bioswale bottom (pages 65, 149); 24 in green gutter (page 67); exfiltration invert ≥2 ft above SHGWT with CAD note 12 in or greater (pages 51–52); alternative pond bottom outfall min 1 ft (page 21). Vegetated BMPs: recover RTV in 24–36 hours (pages 45, 65); general retention RTV recovery within 72 hours with safety factor 2 (pages 47, 220). Retention pond max design infiltration 18 in/hr (1.5 ft/hr); swale min infiltration through vegetation/soil 1 in/hr (pages 21, 68). Exfiltration: min 12 in pipe, min 3 ft trench width (page 52).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "prince-georges-county-md", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/prince-georges-county-md/", "data_url": "https://stormwateratlas.com/data/manuals/prince-georges-county-md.json", "document_metadata": { "jurisdiction_name": "Prince Georges County", "jurisdiction_level": "county", "state_code": "MD", "document_title": "Maryland Stormwater Design Manual (county implements ESD to MEP)", "version_or_edition": "Volume One", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "WQv is calculated as (P)(Rv)(A)/12, where P is the rainfall depth (1.0 inch in the Eastern Rainfall Zone, 0.9 inch in the Western Rainfall Zone), Rv is the volumetric runoff coefficient (0.05 + 0.009 * I), and A is the site area in acres.", "peak_flow_calculation_method": [ "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-20", "TR-55" ], "approved_bmp_categories": [ "Stormwater Ponds", "Stormwater Wetlands", "Infiltration Practices", "Filtering Systems", "Open Channel Practices", "Non-structural Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Prince George's County implements Maryland SWM Design Manual", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "5.2 7.4 Montgomery 2.6 3.2 5.1 7.2 Prince George’s 2.7 3.3 5.3 7.4 Queen Anne’s 2.7 3.3 5.3 7.5 St. Mary’s 2.8 3.4 5.4 7.7 Somerset 2.9 3.5 5.6 8.1 Talbot 2.8 3.4 5.3 7.6 Washington 2.5 3.0 4.8 6.7 Wicomico 2.9 3.5 5.6 7.9 Worcester 3.0 3.6 5.6 8.1", "page_or_section": "pp. 48–49" }, { "field": "document_metadata.state_code", "excerpt": "State of Maryland", "page_or_section": "TOC" }, { "field": "document_metadata.document_title", "excerpt": "Maryland Stormwater Design Manual", "page_or_section": "TOC-1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "adopts_state_manual_directly — Maryland SWM Design Manual ESD to MEP", "page_or_section": "Coverage note" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1, 2, 10, 100 year design storms (Maryland SWM Design Manual)", "page_or_section": "Design criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQv is calculated as (P)(Rv)(A)/12, where P is the rainfall depth (1.0 inch in the Eastern Rainfall Zone, 0.9 inch in the Western Rainfall Zone)", "page_or_section": "WQv chapter" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "computer program fps feet per second TR-55 Technical Release No. 55 Urban Unit Hydrology for Small Watersheds hf head above filter bed TSS total suspended solids HSG hydrologic soil group Vf filter bed volume Ia initial abstraction Vr volume of runoff I percent impervious cove", "page_or_section": "pp. 36–38" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "computer program fps feet per second TR-55 Technical Release No. 55 Urban Unit Hydrology for Small Watersheds hf head above filter bed TSS total suspended solids HSG hydrologic soil group Vf filter bed volume Ia initial abstraction Vr volume of runoff I percent impervious cove", "page_or_section": "pp. 36–38" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "How to Use the Manual The Maryland Stormwater Design Manual is provided in two volumes. This first volume provides designers a general overview on how to size, design, select and locate BMPs at a new development site to comply with State stormwater performance standards. The", "page_or_section": "p. 31" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P= rainfall depth in inches and is equal to 1.0\" in the Eastern Rainfall Zone and 0.9\" in the Western Rainfall Zone", "page_or_section": "Chapter 2, Table 2.1 / Section 2.0, page 39" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Extended Detention for Water Quality Volume: The water quality requirement can be met by providing a 24 hour drawdown of a portion of the water quality volume (WQv)", "page_or_section": "Chapter 2, Section 2.4, page 42" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED 24 hour drawdown of the water quality volume", "page_or_section": "Table 1.3 Key Symbols and Acronyms, page 36" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "filter bed inverts shall be separated at least four feet vertically (two feet on the lower Eastern shore) from the seasonal high water table", "page_or_section": "Chapter 5, Micro-bioretention Treatment, page 245" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Bioretention systems (F-6) shall consist of the following treatment components: A 2½ to 4 foot deep planting soil bed", "page_or_section": "Chapter 3, Section 3.4.5 Filtering, page 121" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 12\" deep surface ponding area", "page_or_section": "Chapter 3, Section 3.4.5 Filtering, page 121" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Flowpaths of 1.5:1 (length relative to width) and irregular shapes are recommended", "page_or_section": "Chapter 3, Section 3.1.4 Pond Treatment Criteria, page 92" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Filter beds shall be between 24 and 48 inches deep", "page_or_section": "Chapter 5, Micro-bioretention, page 245" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Temporary storage of the ESDv may be provided above the facility with a surface ponding depth of 12 inches or less", "page_or_section": "Chapter 5, Micro-bioretention, page 245" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "County-level coverage using Maryland SWM Design Manual Volume 1 (ESD to MEP). Local Prince George's supplements not separately ingested. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://mde.maryland.gov/programs/water/StormwaterManagementProgram/Documents/www.mde.state.md.us/assets/document/sedimentstormwater/MD%20SWM%20Volume%201.pdf", "landing_page_url": "https://mde.maryland.gov/programs/water/stormwatermanagementprogram/pages/stormwater_design.aspx", "retrieved_at": "2026-08-10T09:15:00.000Z", "original_filename": "prince-georges-county-md.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 24, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:50:12.215Z", "enrich_model": "composer-2.5:run-58d25cef-b2de-4a5e-b50b-fb97703c1ae6", "enrich_notes": "WQv rainfall P is 1.0 inch (Eastern Rainfall Zone) or 0.9 inch (Western); excerpts cite both—PG County typically Eastern. SHWT separation also stated as 24 inches (two feet above SHWT for rain gardens) and 24 inches (two feet on lower Eastern Shore for infiltration inverts). Infiltration practices (I-1/I-2) require WQv to infiltrate over a two-day (48 h) period—distinct from 24 h WQv ED. Cpv extended detention is 24 h (12 h in USE III and IV watersheds). Filter permeability k is given in ft/day (e.g., bioretention soil 0.5 ft/day), not in/hr. Micro-bioretention filter beds: 24–48 in deep; rain gardens: 6–12 in planting soil, ponding ≤6 in.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ri-ridot-drainage", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/ri-ridot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ri-ridot-drainage.json", "document_metadata": { "jurisdiction_name": "Rhode Island", "jurisdiction_level": "state", "state_code": "RI", "document_title": "RIDOT Linear Stormwater Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "Water Quality Volume (WQV): The volume of the first inch of runoff from impervious surfaces (WQV = 1-inch X impervious area)", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Infiltration Basin", "Infiltration Trench", "Extended Detention", "Sand Filter", "Vegetated Swale", "Filter Strip", "Oil/Grit Separator", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Rhode Island", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "RIDOT Linear Stormwater Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "foot per second. o Maximum velocity for 10-year design storm: 3 feet per second o If velocities are greater than the maximum ve", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume (WQV): The volume of the first inch of runoff from impervious surfaces (WQV = 1-inch X impervious area)", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Infiltration Basin, Infiltration Trench, Extended Detention", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum allowable temporary ponding time is 48 hours.", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 131" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "fully dewater within 48 hours after a storm event.", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 133" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered soil media shall be 2-4 feet deep planting soil", "page_or_section": "Section 2.3.5 – Bioretention Basin, page 99" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Engineered soil media shall have a depth of 24 inches to 48 inches", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 133" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "the system shall allow 6-12 inches of ponding.", "page_or_section": "Section 2.3.5 – Bioretention Basin, page 99" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "12 inches of ponding depth allowed.", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 131" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum for WQV: 12 inches at longitudinal mid-point of swale", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 133" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "Reservoir Course o Thickness: 4 inches; Increase thickness of reservoir course as needed", "page_or_section": "Section 2.3.4 – Porous Pavement with Storage, page 89" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Use a design infiltration rate of 0.52 inches per hour if a loam surface layer is used.", "page_or_section": "Section 2.3.5 – Bioretention Curb Inlet Planter, page 111" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Construct in locations where in-situ infiltration rates of underlying soils exceed 0.5 inches per hour.", "page_or_section": "Section 2.3.3 – Underground Infiltration System, page 66" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Bottom width no greater than 8 feet, but no less than 2 feet.", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 131" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Minimum: 2 feet", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 133" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Bioretention swales shall have a maximum longitudinal slope of 2% without check dams", "page_or_section": "Section 2.3.5 – Bioretention Swale, page 133" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "There is at least 18 inches of separation to groundwater.", "page_or_section": "Section 2.1.4 Pretreatment Vegetated Filter Strip, page 38" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Bottom of crushed stone reservoir shall be at least 3 feet above SHGT and bedrock.", "page_or_section": "Section 2.3.3 – Underground Infiltration System, page 66" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. RIDOT Linear Stormwater Manual (February 2019)", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.dot.ri.gov/EnvironmentalDivision/docs/Stormwater/Linearstormwatermanual.pdf", "landing_page_url": "https://www.dot.ri.gov/EnvironmentalDivision/Office_of_Stormwater.php", "retrieved_at": "2026-08-11T17:59:10.642Z", "original_filename": "ri-ridot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": 4, "design_infiltration_rate_in_per_hr": 0.52, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:54:02.089Z", "enrich_model": "composer-2.5:run-7ee64bc6-2a3d-4de5-9dd6-7f48111306ef", "enrich_notes": "WQV sizing is referenced (75% WQV in bioretention, WQV orifice 4–8 in below organic soil in gravel wetland) but no explicit WQV rainfall depth in inches in excerpts. SHGT separation varies: 18 in (filter strip/pretreatment), 36 in (3 ft) for many infiltration/bioretention tops or reservoir bottoms. Design infiltration: half field-derived rate or RI Rules values; 0.52 in/hr explicit for loam surface layer; 0.5 in/hr minimum in-situ to use infiltration STUs; do not use infiltration STUs if >8.3 in/hr. Bioretention ponding 6–12 in (basins/planters); swale max WQV ponding 12 in at mid-point. Porous pavement reservoir minimum 4 in (increase as needed). Gravel wetland optional extended detention when inline—no drain time given.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ri-state", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/ri-state/", "data_url": "https://stormwateratlas.com/data/manuals/ri-state.json", "document_metadata": { "jurisdiction_name": "Rhode Island", "jurisdiction_level": "state", "state_code": "RI", "document_title": "RHODE ISLAND STORMWATER DESIGN AND INSTALLATION STANDARDS MANUAL", "version_or_edition": "Amended March 2015", "adoption_or_effective_date": null, "last_revised_date": "March 2015", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 50, 100 ], "water_quality_volume_method": "Equivalent to the runoff associated with the first 1.2 inches of rainfall over the impervious surface (i.e., 1 inch of runoff), calculated as WQv = (1\") (I) / 12", "peak_flow_calculation_method": [ "TR-55", "TR-20", "Rational Method" ], "required_hydrologic_hydraulic_software": [ "TR-55", "TR-20" ], "approved_bmp_categories": [ "Wet Vegetated Treatment Systems (WVTS)", "Infiltration Practices", "Filtering Systems", "Green Roofs", "Open Channel Systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "RHODE ISLAND DEPARTMENT OF ENVIRONMENTAL MANAGEMENT", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "RHODE ISLAND DEPARTMENT OF ENVIRONMENTAL MANAGEMENT AND COASTAL RESOURCES MANAGEMENT COUNCIL", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "The RI Stormwater Design and Installation Standards Manual", "page_or_section": "Effective Date Page" }, { "field": "document_metadata.document_title", "excerpt": "RHODE ISLAND STORMWATER DESIGN AND INSTALLATION STANDARDS MANUAL", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Amended March 2015", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective Date: _______________", "page_or_section": "Effective Date Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Amended March 2015", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "RHODE ISLAND STORMWATER DESIGN AND INSTALLATION STANDARDS MANUAL", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-Year 2-Year 5-Year 10-Year 25-Year 50-Year 100-Year", "page_or_section": "Table 3-1, Page 3-1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required WQv, which results in the capture and treatment of the entire runoff volume for 90 percent of the average annual storm events, is equivalent to the runoff associated with the first 1.2 inches of rainfall over the impervious surface (i.e., 1 inch of runoff).", "page_or_section": "Section 3.3.3, Page 3-13 to 3-14" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The models TR-55 or TR-20 (or approved equivalent) shall be used for determining the CPv. ... The Rational Method may be used for sizing the conveyance system.", "page_or_section": "Section 3.3.4, Page 3-17" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The models TR-55 and TR-20 (or approved equivalent) will be used for determining the required storage and outlet structures", "page_or_section": "Section 3.3.5, Page 3-19" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The five groups of structural BMPs include (1) Wet Vegetated Treatment Systems (WVTS), (2) Infiltration Practices, (3) Filtering Systems, (4) Green Roofs, and (5) Open Channel Practices.", "page_or_section": "Section 1.3, Page 1-5" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "WQv = (1\")(I) / 12 ... use 1.2 inches for the Water Quality Storm that produces 1 inch of runoff from impervious surfaces", "page_or_section": "Appendix D / Atlas context" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time of 48 hours", "page_or_section": "5.3 STORMWATER INFILTRATION PRACTICES, page 103" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Separation from seasonal high groundwater table and bedrock of at least 3 feet except for strictly residential land uses, for which it may be reduced to 2 feet", "page_or_section": "5.3, page 103" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "A 24\" to 48\" deep planting soil bed (depending on requirements of proposed vegetation)", "page_or_section": "5.5.4 Treatment, page 132" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "a 6\" to 9\" deep surface ponding area", "page_or_section": "5.5.4 Treatment, page 132" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Minimum soil infiltration rate of 0.5 inches per hour", "page_or_section": "5.3 FEASIBILITY, page 103" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours", "page_or_section": "5.2 WVTS, page 87" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "For a Shallow WVTS: Minimum flowpath of 2:1 (length to width)", "page_or_section": "5.2 GEOMETRY, page 88" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall be designed with a bottom width no greater than 8 ft ... but no less than 2 ft", "page_or_section": "5.7.4 Treatment, page 148" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Open channels shall have a maximum longitudinal slope of 4%, without check dams", "page_or_section": "5.7.1, page 147" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "All requested metadata and design criteria were explicitly identified in the provided text sections. The exact effective date was not filled in on the copy of the document, so it was set to null.", "fields_not_found": [] }, "source": { "document_url": "https://services.statescape.com/RegsText/StaticDownloads/90765_156853.pdf", "landing_page_url": "https://www.crmc.ri.gov/policy/stormwater.html", "retrieved_at": "2026-08-07T11:28:15.873Z", "original_filename": "ri-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 9, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale" ], "enriched_at": "2026-08-13T09:54:52.011Z", "enrich_model": "composer-2.5:run-0af15d53-0c8e-421b-9baf-a4d7021742c1", "enrich_notes": "WQv sizing uses 1 inch runoff from impervious area (Atlas: 1.2 in rainfall storm producing 1 in runoff). SHGT separation is 3 ft (36 in) generally; 2 ft (24 in) for strictly residential infiltration/permeable paving per Section 5.3/5.4. Bioretention planting soil 24–48 in (12 in case-by-case); ponding zone 6–9 in. Gravel WVTS minimum flowpath L:W is 1:1. Green roof slope limits in Table 5-8: extensive ≤20%, intensive ≤6%. TAP/TARP acronyms appear in glossary only, not as MTD verification requirement.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "riverside-county-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/riverside-county-ca/", "data_url": "https://stormwateratlas.com/data/manuals/riverside-county-ca.json", "document_metadata": { "jurisdiction_name": "Riverside County", "jurisdiction_level": "county", "state_code": "CA", "document_title": "Water Quality Management Plan — Santa Ana Region of Riverside County", "version_or_edition": "Approved October 22, 2012", "adoption_or_effective_date": "2012-10-22", "last_revised_date": "2012-10-22", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Priority Development Projects must implement LID BMPs to infiltrate, evapotranspire, harvest/use, or biotreat runoff. Design Capture Volume (DCV) is based approximately on the 85th percentile 24-hour storm event (isohyetal map Exhibit A). Remaining DCV may be addressed with treatment-control BMPs; hydromodification criteria apply in the Santa Ana Region.", "peak_flow_calculation_method": [ "Design Capture Volume (85th percentile 24-hour)", "LID BMP sizing (area- and volume-based)", "Hydromodification criteria for Santa Ana Region" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "LID BMPs (infiltration, biotreatment, harvest/use)", "Self-retaining areas / site design BMPs", "Treatment control BMPs for remaining DCV", "Hydromodification control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "County of Riverside / Santa Ana Region of Riverside County", "page_or_section": "Cover / Co-Permittees" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "County of Riverside", "page_or_section": "Co-Permittees" }, { "field": "document_metadata.state_code", "excerpt": "Santa Ana Regional Water Quality Control Board", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "WATER QUALITY MANAGEMENT PLAN", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "Date approved by the Santa Ana Regional Water Quality Control Board: October 22, 2012", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "October 22, 2012", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "October 22, 2012", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Order No. R8-2010-0033 MS4 WQMP", "page_or_section": "Introduction" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design Capture Volume (DCV) / 85th percentile 24-hour storm event", "page_or_section": "LID / Exhibit A" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "HYDROMODIFICATION CRITERIA FOR THE SANTA ANA REGION", "page_or_section": "Section 3.6 / Figure 3-7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Implement LID BMPs / LID BMP Design Handbook", "page_or_section": "Section 3.4 / Exhibit C" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "a maximum Drawdown Time of 72 hours has been established", "page_or_section": "Chapter 2, page 38 / Appendix VII reference" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A 72-hour drawn down is usually recommended.", "page_or_section": "Transportation Project Guidance, page 149" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "drawdown period, not to exceed 72 hours?", "page_or_section": "Table 5.3 Infiltration Basins, page 182" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "the bottom of the BMP is less than 10 feet above the \"historic high groundwater mark\"", "page_or_section": "Chapter 2.4.5, page 37" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Groundwater separation should be at least 10 feet from the basin invert to the measured ground water elevation.", "page_or_section": "Transportation Project Guidance, page 149" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "seasonal high groundwater mark shallower than 10 feet?", "page_or_section": "Table D.1 Infiltration Feasibility, page 108" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "the minimum long-term post-development infiltration rate must be at least 0.83 inches per hour (5ft * 12 / 72 hours = 0.83 inches/hour)", "page_or_section": "Chapter 2, page 38" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "tested pre-development infiltration rates must be greater than 1.6 inches per hour", "page_or_section": "Chapter 2, page 38" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "If the average 'in-situ' tested infiltration rate for the site is less than 1.6 inches per hour, LID Infiltration BMPs ... shall not be used.", "page_or_section": "Chapter 2, page 38" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Santa Ana Region WQMP; Santa Margarita/Whitewater regions have separate guidance.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://id3464.securedata.net/moreno-valley/departments/public_works/pdf/MV-WQMP.pdf", "landing_page_url": "https://trans.rctlma.org/wqmp-water-quality-management-plans", "retrieved_at": "2026-08-10T08:45:22.876Z", "original_filename": "riverside-county-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 120, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.83, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T09:56:10.502Z", "enrich_model": "composer-2.5:run-6f1a74ba-f7f4-485f-b21c-f57899377bd0", "enrich_notes": "DCV is based on approximately the 85th percentile 24-hour storm (Exhibit A isohyetal map), not a fixed inch depth in these excerpts. Infiltration BMP feasibility requires average in-situ tested rate greater than 1.6 in/hr (factor of safety 2); typical infiltration basin depth cited as 5 ft for the 0.83 in/hr minimum. Biotreatment applies where KSAT < 0.3 in/hr. Detailed BMP sizing is deferred to the LID BMP Design Handbook (2011).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "salt-lake-city-ut", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/salt-lake-city-ut/", "data_url": "https://stormwateratlas.com/data/manuals/salt-lake-city-ut.json", "document_metadata": { "jurisdiction_name": "Salt Lake City", "jurisdiction_level": "municipality", "state_code": "UT", "document_title": "Salt Lake City Municipal Separate Storm Sewer System (MS4) Storm Water Management Plan", "version_or_edition": "December 2021, Version 2024.1", "adoption_or_effective_date": "2021-12", "last_revised_date": "2024", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Retain on site less than or equal to the 80th percentile storm event (or predevelopment hydrologic condition, whichever is less) for new development ≥1 acre (or common plan ≥1 acre). Redevelopment that increases impervious area by more than 10% must retain the net increase in volume for events ≤ the 80th percentile storm. Detention: limit discharge to 0.2 cfs/acre during the 100-year storm for sites with >15,000 sq ft impervious.", "peak_flow_calculation_method": [ "Rational Method (projects <1 acre)", "SCS Curve Number method (projects ≥1 acre)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "On-site Detention Facilities", "Retention / Volume Reduction", "Low Impact Development (LID)", "Green Infrastructure (GI)", "Structural Water Quality BMPs", "Construction Site Erosion and Sediment Controls", "Pollution Prevention / Good Housekeeping SOPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "SALT LAKE CITY MUNICIPAL SEPARATE STORM SEWER SYSTEM (MS4)", "page_or_section": "Cover, Page 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Permit for Discharge from Salt Lake City's Separate Storm Sewer System (MS4) Permit Number UTS000002", "page_or_section": "Introduction" }, { "field": "document_metadata.state_code", "excerpt": "Utah Pollutant Discharge Elimination System (UPDES) Permit... Utah Department of Environmental Quality (DEQ), Division of Water Quality (DWQ)", "page_or_section": "Section 1.0" }, { "field": "document_metadata.document_title", "excerpt": "STORM WATER MANAGEMENT PLAN", "page_or_section": "Cover, Page 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "December 2021, Version 2024.1", "page_or_section": "Cover, Page 1" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "December 2021, Version 2024.1", "page_or_section": "Cover, Page 1" }, { "field": "document_metadata.last_revised_date", "excerpt": "Version 2024.1", "page_or_section": "Cover, Page 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The City's Storm Water Management Plan (SWMP) was developed to comply with the 2021 Municipal Separate Storm Sewer System (MS4) Utah Pollutant Discharge Elimination System (UPDES) Permit", "page_or_section": "Section 1.0" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Salt Lake City requires all commercial, industrial, and residential developments with impervious areas greater than 15,000 square feet to provide onsite detention facilities to limit the discharge to a pre-development rate of 0.2 cubic feet per second per acre during the 100-year storm.", "page_or_section": "SWMP Summary / Section 7.1.2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "requiring new and redevelopment sites greater than 1-acre (or part of a common plan of development collectively disturbing greater than or equal to 1-acre) to retain less than or equal to the 80th Percentile storm event, or a predevelopment hydrologic condition, whichever is less.", "page_or_section": "SWMP Summary, Pages 11–12" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "If the redevelopment project increases the impervious area by more than 10%, the project will be required to manage rainfall on-site and retain the net increase in volume associated with the precipitation from all rainfall events less than or equal to the 80th percentile storm event.", "page_or_section": "Section 7.1.2, Page 51" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The SLC Design and Process Manual provides specific hydrologic methods (Rational Method for <1-acre projects and SCS Curve Number for all others) for calculating runoff volumes, and for determining the 80th Percentile Storm depth and associated water quality volume.", "page_or_section": "Section 7.1.2, Page 51" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Salt Lake City will implement requirements for structural BMPs for on-site detention, retention, and water quality improvement, where applicable... The City requires the evaluation and inclusion of GI or LID control BMPs to meet these goals, where feasible.", "page_or_section": "Section 7.1.2, Pages 50–51" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The City allows for the use of any suitable BMP from the DWQ LID guidance manual (A Guide to Low Impact Development in Utah).", "page_or_section": "Section 7.1.2, Page 51" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "site-specific calculations of the design storm runoff volumes for the 80th percentile storm event depth", "page_or_section": "salt-lake-city-ut-c0070, page 51 (ENFORCEMENT)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "limit the discharge to a pre-development rate of 0.2 cubic feet per second per acre during the 100-year storm", "page_or_section": "salt-lake-city-ut-c0024, page 11 (Long-Term Storm Water Management)" }, { "field": "practice_mentions.swale", "excerpt": "structural BMPs such as grass swales and detention basins", "page_or_section": "salt-lake-city-ut-c0073, page 54 (BMP 18)" }, { "field": "practice_mentions.extended_detention", "excerpt": "provide onsite detention facilities to limit the discharge to a pre-development rate of 0.2 cubic feet per second per acre during the 100-year storm", "page_or_section": "salt-lake-city-ut-c0024, page 11" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Program plan (MS4 SWMP), not a full drainage design manual. Design criteria summarized from post-construction program text and references to the separate SLC Building Process & Design Manual / DWQ LID guide; numeric 80th-percentile rainfall depth and full BMP design specs live in those companion documents.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.design_storm_return_periods_years (only 100-year detention criterion stated; 80th percentile is a percentile storm, not a return-period year)" ] }, "source": { "document_url": "https://www.slcdocs.com/utilities/Stormwater/SaltLakeCity_MS4_UTS000002_SWMP_v2024.1.pdf", "landing_page_url": "https://www.slc.gov/utilities/", "retrieved_at": "2026-08-08T11:41:33.902Z", "original_filename": "SaltLakeCity_MS4_UTS000002_SWMP_v2024.1.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "swale" ], "enriched_at": "2026-08-13T10:01:06.618Z", "enrich_model": "composer-2.5:run-c39dbd46-b73d-460f-887f-e0477e6d7675", "enrich_notes": "Corpus is the MS4 SWMP, not the SLC Building Process & Design Manual or DWQ LID guide. Retention is tied to the 80th-percentile storm depth and WQV methods are delegated to the Design Manual; no inch-depth for that storm appears here. Detention applies above 15,000 sq ft impervious at 0.2 cfs/acre (100-year). LID/GI from DWQ manual when feasible; no SCM sizing tables in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "san-bernardino-county-ca", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/san-bernardino-county-ca/", "data_url": "https://stormwateratlas.com/data/manuals/san-bernardino-county-ca.json", "document_metadata": { "jurisdiction_name": "San Bernardino County", "jurisdiction_level": "county", "state_code": "CA", "document_title": "Technical Guidance Document for Water Quality Management Plans (Santa Ana River Watershed)", "version_or_edition": "Effective September 19, 2013 (approved June 21, 2013)", "adoption_or_effective_date": "2013-09-19", "last_revised_date": "2013-06-21", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Priority Projects must meet LID performance criteria by retaining/treating the Design Capture Volume (DCV) for the water quality design storm via infiltration, evapotranspiration, biofiltration, or detention near the source. Hydrologic Conditions of Concern (HCOC) performance criteria address hydromodification. Mojave River Watershed has a separate TGD.", "peak_flow_calculation_method": [ "Design Capture Volume (DCV) calculation for LID", "HCOC / hydromodification performance criteria", "LID BMP selection and feasibility evaluation" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "LID preventive / site design measures", "LID mitigative BMPs (infiltration, biotreatment)", "Treatment control BMPs", "HCOC hydromodification mitigation BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "County of San Bernardino Areawide Stormwater Program", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "County of San Bernardino", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Santa Ana Regional / ORDER No. R8-2010-0036", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Technical Guidance Document for Water Quality Management Plans", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "NPDES No. CAS618036 MS4 Order R8-2010-0036", "page_or_section": "Cover" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design Capture Volume or \"DCV\" / LID Performance Criteria", "page_or_section": "Section 4.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "HCOC Performance Criteria / Hydromodification Impacts", "page_or_section": "Section 4.2 / 3.4.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Selection of LID Mitigative Measures and BMPs", "page_or_section": "Section 5.3" }, { "field": "max_drawdown_hours", "excerpt": "An infiltration basin allows retained runoff to percolate into the underlying soils in 48 hours or less.", "page_or_section": "5.4.2.1 Infiltration basin, page 66" }, { "field": "max_drawdown_hours", "excerpt": "Allowable ponding is limited by the requirement to drawdown ponded water within 48 hours following a storm event.", "page_or_section": "5.4.2.2 Infiltration trench, page 66" }, { "field": "max_drawdown_hours", "excerpt": "Tdrawdown = drawdown time for stored runoff (hrs), default is 48 hours", "page_or_section": "Table 5-6, pages 75-75" }, { "field": "bioretention_ponding_depth_inches", "excerpt": "up to 1.5 ft of allowable ponding above the ammended soil layer.", "page_or_section": "5.4.2.3 Bioretention with no Underdrain, page 66" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "Pdesign = design percolation rate into amended soil layer (in/hr), default 2.5 in/hr", "page_or_section": "Table 5-6 Bioretention with underdrain, pages 75-75" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "Amended soil design percolation = 2.5 in/hr", "page_or_section": "Case Study 2 Application of Bioretention with Underdrains, page 73" }, { "field": "ed_drain_time_hours", "excerpt": "Tdrawdown = drawdown time for stored runoff (hrs), default is 48 hours", "page_or_section": "Table 5-6 Constructed wetland / Extended wet detention / Dry extended detention, pages 75-75" }, { "field": "wetland_detention_hours", "excerpt": "Biotreated volume is a function of the HRT for the facility (default is 48 hours for capture of frequent storms in the wet season)", "page_or_section": "Constructed wetland bullet, page 73" }, { "field": "practice_mentions", "excerpt": "Infiltration BMPs - Infiltration trench, infiltration basin, bioretention with no underdrain, drywell, permeable pavement, and underground infiltration", "page_or_section": "5.4 Evaluation of LID BMPs, page 59" }, { "field": "practice_mentions", "excerpt": "Biotreatment BMPs – Bioretention with underdrain, vegetated swale, vegetated filter strip, dry extended detention basin, wet detention basin, constructed wetland, and proprietary biotreatment.", "page_or_section": "5.4 Evaluation of LID BMPs, page 59" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Santa Ana River Watershed TGD; Mojave has separate guidance. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://dpw.sbcounty.gov/wp-content/uploads/sites/87/docs/SantaAnaRiver-WQMP-Final-June2013.pdf", "landing_page_url": "https://dpw.sbcounty.gov/wqmp-templates-and-forms/", "retrieved_at": "2026-08-10T08:48:28.515Z", "original_filename": "san-bernardino-county-ca.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 18, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 2.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": 48, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:01:53.830Z", "enrich_model": "composer-2.5:run-e56466ab-6049-4a6c-97d9-838060ea8ac2", "enrich_notes": "Priority projects must retain/treat Design Capture Volume (DCV) via LID; performance tied to P6 mean storm depths in Table 5-8 for harvest-and-use infeasibility thresholds (0.70–2.30 in), not stated as a single jurisdiction WQv depth. Infiltration BMP design rate is field-measured rate divided by safety factor (must be ≥2.0 and <9). Default 2.5 in/hr applies to amended-soil percolation for bioretention with underdrain sizing (Table 5-6). Residential case study cites <0.3 in/hr underlying soils as infiltration infeasibility example. Infiltration basin, trench, and bioretention without underdrain require 48-hour drawdown/percolation limits where stated.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "broward-county-fl", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/broward-county-fl/", "data_url": "https://stormwateratlas.com/data/manuals/broward-county-fl.json", "document_metadata": { "jurisdiction_name": "South Broward Drainage District", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Stormwater Management Regulations, Standards, Procedures and Design Criteria Manual", "version_or_edition": "March 26, 2015 (Latest Revision February 2015)", "adoption_or_effective_date": "2015-03-26", "last_revised_date": "2015-02-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 3, 100 ], "water_quality_volume_method": "Must meet SFWMD criteria for dry pre-treatment retention/detention plus District water quality and quantity requirements. Discharge limited by basin (e.g., inches of runoff per day per acre for SFWMD C-9 / C-11 basins). Structures protected against 100-year, 3-day storm; second-order drainage systems designed for 3-year rainfall (FDOT Zone 10).", "peak_flow_calculation_method": [ "3-year design for second-order / internal drainage (FDOT Zone 10 IDF)", "100-year, 3-day flood protection / stage criteria", "Allowable discharge rates by SFWMD basin (C-9 / C-11)", "Retention / detention with control structures" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Dry retention / detention", "Wet retention / detention", "Control structures / weirs", "Swales and conveyance systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "SOUTH BROWARD DRAINAGE DISTRICT", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "SOUTH BROWARD DRAINAGE DISTRICT / BROWARD COUNTY, FLORIDA", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "STORMWATER MANAGEMENT REGULATIONS, STANDARDS, PROCEDURES AND DESIGN CRITERIA MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "March 26, 2015 / Latest Revision February 2015", "page_or_section": "Cover" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "March 26, 2015", "page_or_section": "Cover" }, { "field": "document_metadata.last_revised_date", "excerpt": "Latest Revision February 2015", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "supplement the established rules ... South Florida Water Management District (SFWMD)", "page_or_section": "Purpose" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year, 3-day storm event / second-order drainage system ... 3-year", "page_or_section": "Definitions / Design criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "meet SFWMD criteria for dry, pre-treatment retention/detention", "page_or_section": "Water Quality" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "allowable discharge ... inch of runoff per day per acre ... SFWMD C-9 / C-11 basin", "page_or_section": "Discharge Criteria" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "retention systems, detention systems", "page_or_section": "Definitions / criteria" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The minimum longitudinal slope for roadways and roadway swales shall be 0.3% or 0.003 feet per foot.", "page_or_section": "3.7.1 ROADWAY AND SWALE GRADING, page 27" }, { "field": "practice_mentions.swale", "excerpt": "Swale means a man-made trench that: (a) Has a top width-to-depth ratio of the cross-section equal to or greater than 6:1...", "page_or_section": "2.2 DEFINITIONS, page 19" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Exfiltration Trench means an underground drainage system that has the capacity to store and percolate stormwater runoff into the ground water.", "page_or_section": "2.2 DEFINITIONS, page 15" }, { "field": "practice_mentions.extended_detention", "excerpt": "Detention means a system designed to store and retain stormwater with controlled discharge to a lake or receiving body of water.", "page_or_section": "2.2 DEFINITIONS, page 14" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Semi-impervious means land surfaces that partially restrict the penetration of water; such as porous concrete and asphalt pavements, gravel, limerock, and certain compacted soils.", "page_or_section": "2.2 DEFINITIONS, page 19" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "SBDD criteria cover southern Broward; Central Broward WCD has separate manual. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.sbdd.org/pdfs/Criteria%20Manual%202015/Criteria%20Manual-March2015.pdf", "landing_page_url": "https://www.sbdd.org/development-projects/resources/standard-details-pdf/", "retrieved_at": "2026-08-10T08:45:22.876Z", "original_filename": "broward-county-fl.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.3, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T07:40:30.836Z", "enrich_model": "composer-2.5:run-2238f9bb-3751-4faa-bf28-93d062aaadfa", "enrich_notes": "SBDD defers soil storage and water-quality computations to SFWMD Environmental Resource Permit Applicant's Handbook; excerpt cites percolation/K-factor for exfiltration trenches but no numeric in/hr design rate. Dry detention/retention and swale inverts must be at least 1 ft above basin control elevation (CWE), not stated as seasonal high water table separation. Level of service: 10-year 3-day for roads/parking; 100-year 3-day for building finished floors.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "sc-scdot-drainage", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/sc-scdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/sc-scdot-drainage.json", "document_metadata": { "jurisdiction_name": "South Carolina", "jurisdiction_level": "state", "state_code": "SC", "document_title": "SCDOT Stormwater Quality Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 100 ], "water_quality_volume_method": "water quality volume", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Infiltration Trench", "Wet Pond", "Dry Pond", "Filter Strip" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "South Carolina", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "SCDOT Stormwater Quality Design Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "(TSS) for disturbed conditions for the 10-year, 24-hour storm event. When selecting Standard SCDOT BMPs with an applicable SCD", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "water quality volume", "page_or_section": null }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "store and release the first ½ inch of runoff from the entire Project site over a minimum period of 24 hours", "page_or_section": "3.3.3.1 Design Removal Efficiency Goal/Performance Standard, page 3-8" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Design permanent water quality structures not having a permanent pool elevation (dry structures) to store and release the first one (1) inch of runoff from the Project site over a minimum period of 24 hours.", "page_or_section": "3.3.3.1, page 3-8" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "vegetated channels and swales with a slope less than or equal to 1% may be 75 feet long", "page_or_section": "5.1 Post-Construction BMP Policy, page 5-1" }, { "field": "practice_mentions.wet_pond", "excerpt": "Design permanent water quality ponds and detention structures having a permanent pool elevation to store and release the first ½ inch of runoff", "page_or_section": "3.3.3.1, page 3-8" }, { "field": "practice_mentions.extended_detention", "excerpt": "Dry stormwater ponds are constructed stormwater basins that do not have a permanent pool of water.", "page_or_section": "Table 2, page 5-4" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Design permanent water quality infiltration practices to accommodate, at a minimum, the first one (1) inch of runoff from impervious areas", "page_or_section": "3.3.3.1, page 3-8" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Design MTDs to treat at a minimum the peak flow rate of the stormwater runoff from the 1.8-inch, 1-year, 24-hour storm event", "page_or_section": "3.3.3.1, page 3-8" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "retain the first 1½ inches of runoff from built-upon portions of the Project", "page_or_section": "3.3.3.1 shellfish beds, page 3-8" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. SCDOT Stormwater Quality Design Manual (SWQDM) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.scdot.org/content/dam/scdot-legacy/business/pdf/stormwater/SCDOT_SWQDM.pdf", "landing_page_url": "https://www.scdot.org/", "retrieved_at": "2026-08-11T17:59:10.535Z", "original_filename": "sc-scdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 1, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_trench", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:06:49.028Z", "enrich_model": "composer-2.5:run-ceea39b0-82a9-4fb0-b8aa-4090e1e2b3eb", "enrich_notes": "SCDOT uses practice-specific runoff capture depths (0.5 in permanent-pool ponds, 1.0 in dry/detention and infiltration, 1.5 in near shellfish) rather than one global WQv depth in the provided excerpts. Appendix E/F design tables are referenced but not included in corpus. MTD design cites SC-M-815-13, not TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "south-carolina-manual", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/south-carolina-manual/", "data_url": "https://stormwateratlas.com/data/manuals/south-carolina-manual.json", "document_metadata": { "jurisdiction_name": "South Carolina", "jurisdiction_level": "state", "state_code": "SC", "document_title": "South Carolina Stormwater Management BMP Handbook (BMP Field Manual)", "version_or_edition": "July 31, 2005 (structural BMP sections; handbook sections revised through 2025)", "adoption_or_effective_date": null, "last_revised_date": "2005-07-31", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Wet detention ponds: permanent pool volume equals 1 inch of runoff per impervious acre (0.5 inch for wet extended ponds with aquatic bench; 0.1 inch for micropool extended ponds). Dry detention lower stage detains the water quality volume for at least 24 hours.", "peak_flow_calculation_method": [ "Hydrologic analysis for outlet structure sizing (water quality and quantity control)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Erosion Prevention BMPs", "Sediment Control BMPs", "Runoff Control and Conveyance BMPs", "Low Impact Development (LID) BMPs", "Structural Water Quality BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "South Carolina DHEC Storm Water Management BMP Handbook", "page_or_section": "Wet Detention Ponds p.118" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "South Carolina Department of Environmental Services", "page_or_section": "BMP Handbook landing page" }, { "field": "document_metadata.state_code", "excerpt": "construct across or along a stream to South Carolina Department of Environmental Services (SCDES). Temporary stream crossings require authorization. Refer to the US Army Corps of Engineers and SCDES nationwide 401 and 404 regulations for information on permit requirements. When", "page_or_section": "pp. 106–107" }, { "field": "document_metadata.document_title", "excerpt": "Storm Water Management BMP Handbook", "page_or_section": "Wet Detention Ponds p.118" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "SCDES BMP Handbook evaluates numerous Best Management Practices (BMPs)", "page_or_section": "BMP Handbook landing page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Ponds shall be designed for the 2 and 10-year storms; The 100-year storm should not overtop the embankment", "page_or_section": "Dry Detention Ponds" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "design permanent pool volume is equal to 1-inch of runoff per impervious acre on the site", "page_or_section": "Wet Detention Ponds" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Size the outlet structure for water quality control and water quantity control (based upon hydrologic", "page_or_section": "Dry Detention Ponds" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Structural storm water quality controls are classified into the following categories: General Application Controls ... Limited Application Controls", "page_or_section": "Structural Controls p.117" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "gradually exfiltrates through the bottom and sides of the trench into the subsoil over a maximum period of 72 hours (three days)", "page_or_section": "south-carolina-manual-c0062, page 146" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "soils that have a minimum infiltration rate of 0.3-inches per hour", "page_or_section": "south-carolina-manual-c0062, page 146" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "released over 24-hours", "page_or_section": "south-carolina-manual-c0055, page 129 (Wet Extended Pond)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the water quality volume for 24-hours", "page_or_section": "south-carolina-manual-c0055, page 129 (Micropool Extended Pond)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "detain the storm water runoff for the water quality volume for a minimum duration of 24-hours", "page_or_section": "south-carolina-manual-c0057, page 133 (Dry Detention Pond)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "released over a period of 24-hours", "page_or_section": "south-carolina-manual-c0059, page 139 (Extended Detention Shallow Wetland)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Main BMPFieldManual.pdf text is not machine-readable (custom font encoding). Extraction used readable section PDFs from the SC DES BMP Handbook (Wet/Dry Detention Ponds, Structural Controls). Peak-flow software/method details not found in readable sections. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.des.sc.gov/sites/des/files/Documents/BOW/Stormwater/BMP/BMPFieldManual.pdf", "landing_page_url": "https://www.des.sc.gov/programs/bureau-water/stormwater/best-management-practices-bmps/bmp-handbook", "retrieved_at": "2026-08-08T00:57:13.880Z", "original_filename": "south-carolina-manual.extraction.json" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.3, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 24, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:12:07.479Z", "enrich_model": "composer-2.5:run-8f92e4c7-4b45-462b-a23f-dff6ad8aa241", "enrich_notes": "Atlas WQv depths (1.0 / 0.5 / 0.1 in per impervious acre) are not stated in these excerpts. Open vegetated conveyance flat bottom is 2–8 ft wide (pages 123–124). Infiltration trench 72 hr max exfiltration is drawdown, not ED outlet design. Enhanced swale maintenance cites 48 hr drawdown if clogged (page 150).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "sd-dot-esc", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/sd-dot-esc/", "data_url": "https://stormwateratlas.com/data/manuals/sd-dot-esc.json", "document_metadata": { "jurisdiction_name": "South Dakota Department of Transportation (SDDOT)", "jurisdiction_level": "state", "state_code": "SD", "document_title": "Erosion and Sediment Control and Stormwater Management Course Manual", "version_or_edition": "Revised October 2024", "adoption_or_effective_date": null, "last_revised_date": "2024-10", "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Erosion Control BMPs (Temporary/Permanent Seeding, Mulch, Erosion Control Blanket, Flexible Channel Liner, Bonded Fiber Matrix)", "Slope Flow Control / Stormwater Runoff Management (Diversion Berm, Diversion Swale, Pipe Slope Drain)", "Slope and Channel Velocity Controls (Rock Check Dam, Rock Rip Rap, Wattles)", "Outlet Protection", "Sediment Control BMPs (Silt Fence, Inlet Protection, Perimeter Control, Sediment Trap, Sediment Basin)", "Stabilized Construction Entrance/Exit", "Dewatering Sediment Capture BMPs and Flocculants" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The objective of the South Dakota Department of Transportation (SDDOT) Erosion and Sediment Control and Stormwater Management Course", "page_or_section": "Page 1, Introduction" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "SDDOT's Construction activities fall under the provisions of the SDDANR General Permit for Stormwater Discharges Associated with Construction Activities... manage the NPDES in South Dakota.", "page_or_section": "Page 4" }, { "field": "document_metadata.state_code", "excerpt": "South Dakota Department of Transportation (SDDOT)", "page_or_section": "Page 1" }, { "field": "document_metadata.document_title", "excerpt": "SDDOT Erosion and Sediment Control and Stormwater Management Course", "page_or_section": "Page 1" }, { "field": "document_metadata.version_or_edition", "excerpt": "EROSION & SEDIMENT CONTROL Revised October 2024", "page_or_section": "Cover / Table of Contents" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised October 2024", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The information in this training manual is intended for training purposes only and does not take precedence over the SDDOT Standard Specifications for Roads and Bridges, the SDDOT Materials Manual, or any SDDOT Policies and Procedures.", "page_or_section": "Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "All sediment and erosion controls shall be selected, designed, and installed to function properly and withstand a 2 year/24-hour rain event.", "page_or_section": "Page 4" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The stormwater controls must be designed to function properly and withstand a 2-year, 24-hour precipitation event. See Appendix F for instructions to determine your construction site's precipitation for a 2-year, 24-hour event.", "page_or_section": "Appendix B, SDDANR General Permit Section 3.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Erosion Control BMP's... Slope Flow Control/Stormwater Runoff Management... Slope Velocity Controls... Channel Surface Control... Channel Velocity Control... Outlet Protection... Sediment Control BMP's... Inlet Protection... Perimeter Control... Stabilized Entrance Protection", "page_or_section": "Table of Contents, Chapter 3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "of BMP Types Add others as needed 1 Temporary Seeding 8 Bonded Fiber Matrix 15 Side Inlet Protection 22 Construction entrance/exit 2 Permanent Sod or Seed 9 Diversion Berm 16 Culvert Inlet Protection 23 Slope Roughening 3 Mulch (hydraulic) 10 Diversion Swale 17 Sediment Trap", "page_or_section": "pp. 58–60" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Sediment capture BMP's... Flocculants", "page_or_section": "Table of Contents, Chapter 7 Dewatering" }, { "field": "practice_mentions.swale", "excerpt": "they improve the efficiency of other sediment controls, such as vegetated swales, filter strips, or infiltration devices", "page_or_section": "sd-dot-esc-c0017, page 16, Slope Flow Control" }, { "field": "practice_mentions.swale", "excerpt": "Check dams – are small dams constructed in an open channel, swale, or ditch.", "page_or_section": "sd-dot-esc-c0018, page 17, Channel Velocity Control" }, { "field": "practice_mentions.swale", "excerpt": "structural stormwater management practices such as stormwater ponds, open vegetated swales, natural depressions to allow infiltration of runoff onsite", "page_or_section": "sd-dot-esc-c0122, page 95, 5.3 SWPPP Post-Construction Stormwater Management" }, { "field": "practice_mentions.wet_pond", "excerpt": "structural stormwater management practices such as stormwater ponds, open vegetated swales, natural depressions to allow infiltration of runoff onsite", "page_or_section": "sd-dot-esc-c0122, page 95" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "natural depressions to allow infiltration of runoff onsite", "page_or_section": "sd-dot-esc-c0122, page 95" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Check dams are generally placed in areas where the slope is 6% or greater combined with a large drainage area", "page_or_section": "sd-dot-esc-c0018, page 17 — contextual only; not a required swale design slope" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Construction ESC training course manual (Oct 2024), not a post-construction hydrologic design manual. Only explicit design storm is the 2-year/24-hour precipitation event for temporary ESC controls (manual + appended SDDANR CGP). No water quality volume sizing, peak-flow hydrology methods, or required modeling software found in the text.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://dot.sd.gov/media/kywakwy4/escontrolsw.pdf", "landing_page_url": "https://dot.sd.gov/Doing-Business/Environmental/Stormwater", "retrieved_at": "2026-08-08T10:30:00.000Z", "original_filename": "sd-dot-esc.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:08:38.283Z", "enrich_model": "composer-2.5:run-d7c288d2-3c4d-4a53-b673-90dbceb2f947", "enrich_notes": "SDDOT erosion and sediment control training manual (Oct 2024) with appended SD DANR construction general permit. Focus is temporary construction BMPs, SWPPP, inspections, and dewatering (53 mg/L TSS limit). Post-construction section names stormwater ponds, open vegetated swales, and infiltration conceptually but gives no sizing depths, drawdown times, infiltration rates, or WQv. Check dams referenced where channel slope is 6% or greater (placement condition, not swale design slope). Level spreader at zero percent grade. No TAPE/NJCAT or manufactured-treatment programs.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fl-sfwmd-erp-ah2", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-sfwmd-erp-ah2/", "data_url": "https://stormwateratlas.com/data/manuals/fl-sfwmd-erp-ah2.json", "document_metadata": { "jurisdiction_name": "South Florida Water Management District (SFWMD)", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II For Use Within the Geographic Limits of the South Florida Water Management District", "version_or_edition": "AH Vol. II (6/28/24)", "adoption_or_effective_date": "2024-06-28", "last_revised_date": "2024-06-28", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 25, 100 ], "water_quality_volume_method": "Water quality treatment volumes and pollutant load-reduction requirements are set forth in ERP Applicant's Handbook Volume I; Volume II adds SFWMD-specific retention/detention criteria (e.g., commercial/industrial projects provide a minimum of 20% of the AH Vol. I load reduction in a retention BMP; exfiltration trenches sized for AH Vol. I water quality requirements exfiltrated over one hour prior to overflow; treatment volume in retention/exfiltration systems is not discharged to surface waters).", "peak_flow_calculation_method": [ "Pre- and post-development runoff hydrographs with detention routing (stage-storage-discharge)", "SCS Peak Rate Factor (K') method", "NRCS National Engineering Handbook Section 4, Part 630, Chapter 10 (peak factors)", "Rational method (for water quality retention/detention)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention systems (depressional areas, shallow landscaped areas, vegetated swales)", "Dry retention/detention", "Wet detention", "Exfiltration trench (underground)", "Above Ground Impoundment (AGI)", "Grassed waterways / spreader swales" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "South Florida Water Management District (SFWMD)", "page_or_section": "Title / district handbook" }, { "field": "document_metadata.jurisdiction_name", "excerpt": "South Florida Water Management District (SFWMD)", "page_or_section": "Title / district handbook" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Florida water management district (ERP Applicant's Handbook Volume II)", "page_or_section": "Chapter 62-330, F.A.C. / district handbook" }, { "field": "document_metadata.state_code", "excerpt": "South Florida Water Management District Clerk's Office, 3301 Gun Club Road, West Palm Beach, FL 33406", "page_or_section": "Section 4.1.1 / references" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II FOR USE WITHIN THE GEOGRAPHIC LIMITS OF THE SOUTH FLORIDA WATER MANAGEMENT DISTRICT", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "AH VOL. II (6/28/24)", "page_or_section": "Header / Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE JUNE 28, 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "EFFECTIVE JUNE 28, 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Volume provides specific, detailed stormwater quality and quantity design and performance criteria for SWM systems regulated by the District through the ERP program authorized under Part IV of Chapter 373, F.S.", "page_or_section": "Section 1.0 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Unless otherwise specified by previous Agency permits, criteria, or Appendix A to this Volume, a 25-year, 3-day storm event shall be used in computing off-site discharge rates.", "page_or_section": "Section 3.2 Design Storm" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Building floors shall be at or above the 100-year flood elevations... Both tidal flooding and the 100-year, 3-day storm event shall be considered in determining elevations.", "page_or_section": "Section 3.3 Flood Protection of Building Floors" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Road crown: Frequency: 5-year... Parking lots: Frequency: 5-year", "page_or_section": "Section 3.4 Flood Protection of Roads and Parking Lots" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Commercial or industrial zoned projects shall provide a minimum of 20% of the load reduction required by AH Vol. I in a retention BMP or a separate containment system designed to prevent discharge.", "page_or_section": "Section 4.1.1 Land Use and Coverage Criteria" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Systems shall be designed for the water quality requirements set forth in AH Vol. I, exfiltrated over one hour for retention purposes, prior to overflow, and based on test data for the site.", "page_or_section": "Section 4.3 Underground Exfiltration Trench Systems" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Unlike detention basins, the treatment volume for retention systems is not discharged to surface waters.", "page_or_section": "Section 5.2.1 Retention System Description" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "An acceptable historic peak discharge analysis typically consists of generating pre-development and post-development runoff hydrographs, routing the post-development hydrograph through a detention basin, and sizing an overflow structure to control post-development discharges at or below pre-development rates.", "page_or_section": "Section 3.2.1 Methodologies" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Historic peak discharge calculations must make proper use of the SCS Peak Rate Factor or K' Factor.", "page_or_section": "Section 3.2.1 Methodologies" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The usual methods of computation are as follows: (a) Rainfall minus losses and storage. (b) U.S. Department of Agriculture, Natural Resources Conservation Service, \"National Engineering Handbook, Section 4, Part 630, Chapter 10 – 2004.\" ... (c) Rational method, for water quality retention/detention purposes.", "page_or_section": "Section 5.6.6 Runoff" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Examples of retention systems include: (a) Man-made or natural depressional areas... (b) Shallow landscaped areas designed to store stormwater; and (c) Vegetated swales with swale blocks or raised inlets.", "page_or_section": "Section 5.2.1 Retention System" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wet detention systems... Dry retention/detention areas... Exfiltration trench systems", "page_or_section": "Sections 5.2.3, 5.3, 5.5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "\"Above Ground Impoundment (AGI)\" – a type of dam... Appendix B AGIs... Appendix C Exfiltration System Trench Design", "page_or_section": "Section 2.1.1; Appendices" }, { "field": "practice_mentions.extended_detention", "excerpt": "\"Retention/detention area (dry)\" – Water storage area with bottom elevation at least 1.0-feet above the control elevation", "page_or_section": "2.1.13, page 8" }, { "field": "practice_mentions.wet_pond", "excerpt": "\"Wet detention systems\" – Permanently wet ponds which are designed to slowly release collected stormwater runoff through an outlet structure.", "page_or_section": "2.1.17, page 8" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "Man-made or natural depressional areas where the basin bottom is graded flat and vegetation is established to promote infiltration", "page_or_section": "5.2.1(a), page 28" }, { "field": "practice_mentions.bioretention", "excerpt": "Shallow landscaped areas designed to store stormwater", "page_or_section": "5.2.1(b), page 28" }, { "field": "practice_mentions.swale", "excerpt": "Vegetated swales with swale blocks or raised inlets.", "page_or_section": "5.2.1(c), page 28" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "Minimum pipe diameter: 12.0-inch diameter. (b) Minimum trench width: 3.0 feet.", "page_or_section": "5.5.2, pages 32-33" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Canonical SFWMD ERP AH Vol II special_district record. City proxies (miami-fl, etc.) remain for municipal map coverage.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.sfwmd.gov/sites/default/files/documents/swerp_applicants_handbook_vol_ii.pdf", "landing_page_url": "https://www.sfwmd.gov/", "retrieved_at": "2026-08-11T18:38:36.243Z", "original_filename": "fl-sfwmd-erp-ah2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:16:07.188Z", "enrich_model": "composer-2.5:run-62a051a5-bcc0-49a3-8d7d-fe6fddf3935f", "enrich_notes": "Volume II defines dry vs wet retention/detention (dry bottom ≥1.0 ft above control elevation; wet bottom lower than 1.0 ft above control). Retention and exfiltration trench treatment volumes are not discharged to surface waters. Exfiltration trenches: minimum 12-inch pipe, 3.0-ft trench width, filter wrap, inlet sumps. Residential minimum drainage cites 0.375 in/day discharge capability and lowering SWM stages within 12 days (not mapped to schema hour fields). Parking lots with exfiltration trenches use 5-year, 1-hour flood criteria; other parking lots use 1-day duration. Subsurface infiltration reviewed from applicant test data only; no universal design in/hr rate in excerpts. WQ treatment volumes referenced to AH Vol I, not numerically stated here.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fl-swfwmd-erp-ah2", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-swfwmd-erp-ah2/", "data_url": "https://stormwateratlas.com/data/manuals/fl-swfwmd-erp-ah2.json", "document_metadata": { "jurisdiction_name": "Southwest Florida Water Management District (SWFWMD)", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II — Design Requirements for Stormwater Treatment and Management Systems: Water Quality and Water Quantity", "version_or_edition": "Effective June 1, 2018 (draft text with NEW DATE markers)", "adoption_or_effective_date": "2018-06-01", "last_revised_date": "2018-06-01", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 25, 100 ], "water_quality_volume_method": "District Vol. II criteria work with statewide ERP Applicant's Handbook Volume I performance standards: wet detention sized for one inch of runoff from the contributing area; retention, effluent filtration, or exfiltration sized for one-half inch of runoff (or, for several BMP types, treat runoff from the first one inch of rainfall, with an option for drainage areas under 100 acres of the first one-half inch of runoff). Treatment volume must again be available within 72 hours (only the portion recoverable in 36 hours may count toward quantity storage). Direct OFW discharges require 50% more treatment volume than the selected system.", "peak_flow_calculation_method": [ "Historic peak discharge or legally allowable discharge (open basins)", "NRCS Type II Florida Modified 24-hour rainfall distribution with AMC II on SWFWMD 24-hour/25-year (open) or 24-hour/100-year (closed) rainfall maps", "Soil Conservation Service / NRCS National Engineering Handbook Section 4 hydrology methods", "Rainfall minus losses and storage", "Rational method (projects less than 10 acres total contributing area)", "USDA-SCS TR-55 Urban Hydrology for Small Watersheds / Technical Paper No. 149 (infiltration)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet detention systems", "Detention with effluent filtration (manmade underdrains)", "On-line retention treatment systems", "Off-line retention treatment systems", "Underground exfiltration treatment systems", "Dry grassed swales / sediment-oil-grease pretreatment", "Sensitive karst area stormwater systems" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Southwest Florida Water Management District (SWFWMD)", "page_or_section": "Title / district handbook" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Florida water management district (ERP Applicant's Handbook Volume II)", "page_or_section": "Chapter 62-330, F.A.C. / district handbook" }, { "field": "document_metadata.state_code", "excerpt": "administration of Chapter 62-330, Florida Administrative Code (F.A.C.).", "page_or_section": "Section 1.0 Introduction" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II DESIGN REQUIREMENTS FOR STORMWATER TREATMENT AND MANAGEMENT SYSTEMS WATER QUALITY AND WATER QUANTITY", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "EFFECTIVE June 1, 2018NEW DATE", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "EFFECTIVE June 1, 2018", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "EFFECTIVE June 1, 2018", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Each Water Management District has adopted an ERP Applicant's Handbook Volume II ... District-specific design and performance criteria for stormwater quantity or, flood control systems, design criteria for stormwater quality systems", "page_or_section": "Section 1.0 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "off-site discharges and peak stages for the existing and developed conditions shall be computed using the Southwest Florida Water Management District's 24-hour, 25-year rainfall maps and the Natural Resources Conservation Service type II Florida Modified 24-hour rainfall distribution", "page_or_section": "Section 3.1 Discharges" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the required retention volume shall be the post-development runoff volume less the pre-development runoff volume computed using the Southwest Florida Water Management District's 24-hour/100-year rainfall map", "page_or_section": "Section 3.1 Discharges (closed basin)" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the proposed stormwater management system shall not be required to account for storm events less frequent than the 25-year event for the rate of discharge in an open basin or the 100-year event for the volume of discharge in a closed basin.", "page_or_section": "Section 3.1.e" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required water quality system must have treatment capacity for one inch of runoff if wet detention is used, or one-half inch of runoff if retention, effluent filtration or exfiltration is used, from the total developed site and contributing offsite area.", "page_or_section": "Section 3.5 / water quality capacity" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "A wet detention treatment system shall be designed to meet the stormwater quality treatment criteria specified in Part II of Volume I.treat one inch of runoff from the contributing area.", "page_or_section": "Section 4.1.a Wet Detention Systems" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat the runoff from the first one inch of rainfall; or as an option for projects or project subunits with drainage areas less than 100 acres, the first one-half inch of runoff.", "page_or_section": "Section 4.1.b Detention with Effluent Filtration" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Projects discharging directly into Outstanding Florida Waters (OFW) shall be required to provide treatment for a volume 50 percent more than required for the selected treatment system", "page_or_section": "Section 4.1.f" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Total treatment volume shall again be available within 72 hours, however, only that volume which can again be available within 36 hours may be counted as part of the volume required for water quantity storage", "page_or_section": "Section 4.1.c On-line Retention" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "historic discharge, which is the peak rate at which runoff leaves a parcel of land by gravity under existing site conditions, or the legally allowable discharge at the time of permit application", "page_or_section": "Section 3.1.a" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Natural Resource Conservation Service Type II Florida Modified rainfall distribution will be used unless the applicant demonstrates that a different distribution better characterizes the actual rainfall distribution", "page_or_section": "Section 6.3 Rainfall Distribution" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Soil Conservation Service design methods (see, for example, U.S. Department of Agriculture, Soil Conservation Service, \"National Engineering Handbook, Section 4, Hydrology.\"", "page_or_section": "Section 6.7 Runoff" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational method, for systems serving projects of less than 10 acres total contributing area.", "page_or_section": "Section 6.7.c" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "a. Wet Detention Systems ... b. Detention with Effluent Filtration System (Manmade Underdrains) ... c. On-line Treatment Systems ... d. Off-line Treatment Systems ... e. Underground Exfiltration Systems", "page_or_section": "Part IV Table of Contents / Section 4.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Normally, a dry grassed swale system designed for detention of the first one-fourth inch of runoff with an overall depth of no more than 4 inches will satisfy the requirement for prior removal of sediment, oils and greases.", "page_or_section": "Section 4.1.a.3" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Especially iIn sensitive karst areas, stormwater management systems must be designed and", "page_or_section": "Section 5.10 Sensitive Karst Areas" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "treat one inch of runoff from the contributing area", "page_or_section": "4.1.a.1, page 24" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "one-half inch of runoff if retention, effluent filtration or exfiltration is used", "page_or_section": "Section 3.5.a, page 22" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Total treatment volume shall again be available within 72 hours", "page_or_section": "4.1.c.2 / 4.1.d.2, pages 26-27" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the bottom of the exfiltration pipe", "page_or_section": "4.1.e.3, page 27" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water level must be at least one foot below the center line of the perforated pipe", "page_or_section": "4.1.b.2, page 25" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Credit for the PPV is limited to a maximum depth of 8 feet", "page_or_section": "4.1.a.3, page 24" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The total detention volume shall again be available within 36 hours", "page_or_section": "4.1.b.4, page 26" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "discharge ½ inch of detention runoff (mixing volume) from the contributing area in 24 hours", "page_or_section": "4.1.a.3, page 24" }, { "field": "practice_mentions.swale", "excerpt": "dry grassed swale system designed for detention of the first one-fourth inch of runoff with an overall depth of no more than 4 inches", "page_or_section": "4.1.a.3(c), page 25" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Canonical SWFWMD ERP AH Vol II special_district record. City proxies (tampa-fl, lakeland-fl) remain for municipal map coverage.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.swfwmd.state.fl.us/sites/default/files/medias/documents/draftswfwmd-erpapplicanthandbook-volume-ii.pdf", "landing_page_url": "https://www.swfwmd.state.fl.us/business/epermitting/rules", "retrieved_at": "2026-08-11T18:38:36.244Z", "original_filename": "fl-swfwmd-erp-ah2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 96, "ed_drain_time_hours": 36, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_trench", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:18:18.691Z", "enrich_model": "composer-2.5:run-a0c7497e-4ed2-4221-a85c-dc2adc0f51bb", "enrich_notes": "WQ treatment depth is BMP-specific in Vol. II: wet detention sized for 1.0 inch of runoff from the contributing area; retention, detention with effluent filtration, and exfiltration treat the first 1.0 inch of rainfall (or 0.5 inch runoff option for drainage areas under 100 acres). Wet detention treatment volume must discharge over no less than 120 hours (max one-half volume in first 60 hours); mixing volume drawdown via v-notch is 24 hours for 0.5 inch runoff. Exfiltration design applies safety factor 2.0 to rate (no numeric in/hr in excerpt). Dry grassed swale pretreatment: first 0.25 inch runoff, overall depth max 4 inches. Filter media minimum vertical path 24 inches (2 feet) before perforated pipe.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "spokane-wa", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/spokane-wa/", "data_url": "https://stormwateratlas.com/data/manuals/spokane-wa.json", "document_metadata": { "jurisdiction_name": "Spokane County / City of Spokane / City of Spokane Valley", "jurisdiction_level": "special_district", "state_code": "WA", "document_title": "Spokane Regional Stormwater Manual", "version_or_edition": "April 2008", "adoption_or_effective_date": "2008-04", "last_revised_date": "2008-04", "relationship_to_state_manual": "deemed_equivalent_to_state_manual" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 100 ], "water_quality_volume_method": "Basic Requirement No. 3 Water Quality Treatment: size treatment BMPs for the volume (or peak) equivalent of the 6-month NRCS Type II 24-hour water quality storm; 6-month precipitation ≈ 0.69 × 2-year precipitation. Flow control (Basic Requirement No. 4) and conveyance (Basic Requirement No. 5) apply per chapters 7–8.", "peak_flow_calculation_method": [ "NRCS Type II 24-hour storms with regional isopluvial maps (2-, 10-, 25-, 100-year)", "Flow control outflow structures (Chapter 7)", "Natural and constructed conveyance systems (Chapter 8)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Basic treatment BMPs", "Metals treatment BMPs", "Phosphorus treatment BMPs", "Bioinfiltration / biofiltration", "Oil-water separators", "Flow control / detention facilities" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Spokane County, City of Spokane, City of Spokane Valley", "page_or_section": "Title / prepared by" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Spokane Regional Stormwater Manual", "page_or_section": "Title" }, { "field": "document_metadata.state_code", "excerpt": "Eastern Washington / SWMMEW", "page_or_section": "Introduction" }, { "field": "document_metadata.document_title", "excerpt": "SPOKANE REGIONAL STORMWATER MANUAL", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "meets or exceeds applicable criteria from the Washington State Department of Ecology’s Stormwater Management Manual for Eastern Washington (SWMMEW)", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year, 10-year, 25-year, 100-year, 24 hour Isopluvial Map", "page_or_section": "Chapter 5 figures" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "treat the volume equivalent of the 6-month NRCS Type II 24-hour water quality", "page_or_section": "Chapter 6" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Basic Requirement No. 4 - Flow Control", "page_or_section": "Chapter 2 / 7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Basic Treatment / Metals Treatment / Phosphorus Treatment", "page_or_section": "Chapter 6" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Detention and infiltration facilities shall have a minimum subgrade infiltration rate of 0.15 inches/hour and drain completely within 72 hours after a storm event.", "page_or_section": "Chapter 7 – 7.8.3 Drawdown Time" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The facility shall drain within 72 hours of a storm event.", "page_or_section": "Appendix 3B Standard Notes item 12" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "For a pond or swale with no infiltrative structure, the separation shall be a minimum of 4.5 ft below the pond bottom, to allow for a 6-inch treatment zone and 48 inches of subgrade infiltrative soil.", "page_or_section": "Appendix 4A / Chapter 7.5.2 Limiting Layer" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Treatment Zone—The layer of soil in a bio-infiltration swale where water quality treatment occurs. It consists of sod installed over medium- to well-draining soil at least 6 inches thick underlain by a subgrade infiltration layer at least 48 inches thick.", "page_or_section": "Glossary page xxii" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Use a treatment depth of 6 inches", "page_or_section": "Appendix 6A – Example Calculation: Bio-Infiltration Swale" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Detention and infiltration facilities shall have a minimum subgrade infiltration rate of 0.15 inches/hour and drain completely within 72 hours after a storm event.", "page_or_section": "Chapter 7 – 7.8.3 Drawdown Time" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The facility subgrade shall be a medium- to well-draining material, with a minimum thickness of 48 inches and a minimum infiltration rate of 0.15 in/hr.", "page_or_section": "Appendix 3B Standard Notes item 12" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "The drainage facility bottom shall slope away from the pond inlet and toward the control structure at 1% for a maximum distance of 20 feet.", "page_or_section": "Chapter 7 – 7.8 (roadside swale)" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "The TRC established the conditional use level designation (CULD) for emerging technologies that have a considerable amount of performance data but the data were not collected per the TAPE protocol.", "page_or_section": "Chapter 6 – 6.29 (Manufactured Treatment)" }, { "field": "design_parameters.mtd_verification_program", "excerpt": "The field data must meet the statistical goals set out in the TAPE guidelines (Appendix D).", "page_or_section": "Chapter 6 – Conditional Use Level Designation" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Regional 2008 SRSM still widely cited; confirm local adoption of Ecology SWMMEW updates. Pipeline excerpt repair removed 3 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.spokanecounty.gov/DocumentCenter/View/1640/Spokane-Regional-Stormwater-Manual-PDF", "landing_page_url": "https://www.spokanecounty.gov/918/Stormwater-Utility", "retrieved_at": "2026-08-10T08:24:40.117Z", "original_filename": "spokane-wa.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 54, "bioretention_media_depth_min_inches": 6, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.15, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 1, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": "TAPE", "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "manufactured_treatment", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:13:24.705Z", "enrich_model": "composer-2.5:run-83cb99f7-c646-491e-9047-89697d12cedd", "enrich_notes": "WQv sizing references 6-month NRCS Type II 24-hour storm (Atlas); no explicit rainfall depth in inches in excerpts. Treatment zone infiltration minimum 0.25–0.50 in/hr cited separately for WQ facilities (Std. Notes item 12). Limiting-layer separation 4.5 ft below pond bottom is to bedrock/GW/limiting layer, not SHWT by name. Bio-infiltration mapped from manual term bio-infiltration swale/pond.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent" ] } }, { "slug": "fl-sjrwmd-erp-ah2", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-sjrwmd-erp-ah2/", "data_url": "https://stormwateratlas.com/data/manuals/fl-sjrwmd-erp-ah2.json", "document_metadata": { "jurisdiction_name": "St. Johns River Water Management District (SJRWMD)", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II (St. Johns River Water Management District)", "version_or_edition": "June 28, 2024", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 5, 10, 25, 100 ], "water_quality_volume_method": "Minimum state water quality treatment and performance standards are those in statewide ERP Applicant's Handbook Volume I; SJRWMD Volume II provides District-specific design/performance standards for water quality and quantity, erosion/sediment control, and BMP criteria within SJRWMD geographic limits (Part IV Stormwater Quality).", "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "Modified Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Wet Pond", "Vegetated Swale", "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "St. Johns River Water Management District", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "SJRWMD ERP Applicant's Handbook Volume II", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "ting centerline road grade is above the 10-year flood elevation, and provided that no increase in upstream flooding is caused.", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "e in 40C-4.091(1)(e)). (b) The modified rational method (see Appendix C of this Volume, incorporated by reference in 40C-4.091(1", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Wet Pond, Vegetated Swale, Detention Basin, Retention Basin", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Design and performance standards and criteria for water quality and quantity ... Part IV - Stormwater Quality", "page_or_section": "Introduction / Part IV" }, { "field": "max_drawdown_hours", "excerpt": "The retention system must provide the capacity for the appropriate treatment volume of stormwater specified in section 5.2 within 72 hours following a storm event", "page_or_section": "5.3 Recovery Time, page 40" }, { "field": "max_drawdown_hours", "excerpt": "The system should be designed to provide for the drawdown of the appropriate treatment volume specified in section 6.2 within 72 hours following a storm event.", "page_or_section": "6.3 Recovery Time, page 42" }, { "field": "max_drawdown_hours", "excerpt": "Swale systems must provide the capacity for the specified treatment volume of stormwater and contain no contiguous areas of standing or flowing water within 72 hours following the storm event", "page_or_section": "9.3 Recovery Time, page 59" }, { "field": "shwt_separation_inches", "excerpt": "The exfiltration trench system must be designed so that the invert elevation of the trench is at least two feet above the seasonal high ground water table elevation", "page_or_section": "7.8 Ground Water Table, page 51" }, { "field": "practice_mentions", "excerpt": "Examples of retention systems include: ... Pervious concrete with continuous curb", "page_or_section": "5.1 Description, page 38" }, { "field": "practice_mentions", "excerpt": "7.0 Exfiltration Trench Design and Performance Criteria", "page_or_section": "Part V, page 47" }, { "field": "practice_mentions", "excerpt": "9.0 Swale Systems Design and Performance Criteria", "page_or_section": "Part V, page 57" }, { "field": "practice_mentions", "excerpt": "8.0 Wet Detention Design and Performance Criteria ... permanently wet ponds", "page_or_section": "8.1 Description, page 52" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Canonical SJRWMD ERP AH Vol II special_district record. Heuristic bootstrap extract; needs human review. East-FL city placeholders point here.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://aws.sjrwmd.com/SJRWMD/permitting/SJRWMD_Applicants_Handbook_Volume_II_6-28-24.pdf", "landing_page_url": "https://www.sjrwmd.com/", "retrieved_at": "2026-08-11T18:39:24.874Z", "original_filename": "fl-sjrwmd-erp-ah2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:16:47.297Z", "enrich_model": "composer-2.5:run-f201dab4-bdc0-4801-9cec-2ac943bd093d", "enrich_notes": "Treatment volume sizing references ERP Applicant's Handbook Volume I (sections 8.3 and 9.0); no WQv depth in inches in Vol II excerpts. Retention, underdrain, exfiltration trench, and swale share 72-hour treatment-volume recovery under average AMC; optional safety factor example uses 36-hour drawdown. System-wide quantity recovery for detention/retention storage is 14 days (3.2.7); wet detention draws down volume above permanent pool within 14 days. Exfiltration trench invert must be at least 2 ft above seasonal high groundwater (7.8). Swale geometry: top width-to-depth ≥ 6:1 or side slopes ≥ 3:1 (H:V).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "hawaii-dot-pcbmp", "processed_at": "2026-08-17T03:19:55.610Z", "detail_url": "https://stormwateratlas.com/hawaii-dot-pcbmp/", "data_url": "https://stormwateratlas.com/data/manuals/hawaii-dot-pcbmp.json", "document_metadata": { "jurisdiction_name": "State of Hawaii Department of Transportation, Highways Division", "jurisdiction_level": "state", "state_code": "HI", "document_title": "Storm Water Post-Construction Best Management Practices Manual", "version_or_edition": "December 2021 (Revision No. 1)", "adoption_or_effective_date": "2021-12-01", "last_revised_date": "2021-12-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Volume-based treatment uses Water Quality Volume (WQV) = P × C × AT × 3630, where P is a 1-inch design storm runoff depth representing the statewide 85th-percentile 24-hour storm; C = 0.95 for impervious highway surfaces. Flow-based treatment uses Water Quality Flow Rate (WQFR) = C × i × AT with Rational Method rainfall intensity i = 0.4 in/hr maintainable for at least three hours.", "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Buffer Strip", "Vegetated Swale", "Enhanced Swale", "Infiltration Trench", "Infiltration Basin", "Bioretention Facility", "Permeable Pavement", "Pocket Wetland", "Rainwater Harvesting", "Tree Box Filter", "Wet Pond", "Wet Extended Detention Pond", "Sand Filter", "Drain Inlet Filter", "Modified Catch Basin", "Oil and Grit Separator", "Centrifugal Hydrodynamic Separator", "Multi-Stage Hydrodynamic Separator", "Source Control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "State of Hawaii Department of Transportation Highways Division", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "State of Hawaii Department of Transportation Highways Division", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "State of Hawaii Department of Transportation", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Storm Water Post-Construction Best Management Practices Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "December 2021", "page_or_section": "Title Page; Record of Revision" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revision No. 1 December 2021 Revised criteria for MS4 NPDES Permit areas", "page_or_section": "Record of Revision" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revision No. 1 December 2021", "page_or_section": "Record of Revision" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Private construction projects located outside the DOT-HWYS right-of-way are considered to be in compliance with post-construction BMP requirements if the project complies with the storm water quality requirements of the applicable county.", "page_or_section": "Section 3.1.3, Page 3-3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = P x C x AT x 3630 Where WQV = Water Quality Volume (ft3) P = Design Storm Runoff Depth (inches) = 1 inch", "page_or_section": "Section 7.3.1, Page 7-6" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "DOT-HWYS determined that a 1-inch runoff depth correctly models the volume required for post-construction BMP treatment.", "page_or_section": "Section 7.2, Page 7-4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQFR = C x i x AT Where WQFR = Water Quality Flow Rate (cfs) i = Rainfall Intensity (in/hr) = 0.4 in/hr", "page_or_section": "Section 7.3.2, Page 7-7" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Flow rate calculation shall be based upon the Rational Method as follows: WQFR = C x i x AT", "page_or_section": "Section 7.3.2, Page 7-7" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "LID TREATMENT CONTROL BMPs: Vegetated Buffer Strip, Vegetated Swale, Enhanced Swale, Infiltration Trench, Infiltration Basin, Bioretention Facility, Permeable Pavement, Pocket Wetland, Rainwater Harvesting, Tree Box Filter", "page_or_section": "Appendix A, Page v" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "TRADITIONAL NON-LID TREATMENT CONTROL BMPs: Wet Pond, Wet Extended Detention Pond, Sand Filter", "page_or_section": "Appendix A, Page v" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "PROPRIETARY NON-LID TREATMENT CONTROL BMPs: Drain Inlet Filter, Modified Catch Basin, Oil and Grit Separator, Centrifugal Hydrodynamic Separator, Multi-Stage Hydrodynamic Separator", "page_or_section": "Appendix A, Page v" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = Design Storm Runoff Depth (inches) = 1 inch", "page_or_section": "7.3.1 Volume-Based Water Quality Control, page 56" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum drawdown time (t): 48 hours", "page_or_section": "Infiltration Trench Design Criteria, A-22" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Maintain at least 3 feet clearance between the bottom of the infiltration trench and the seasonally high groundwater table", "page_or_section": "Infiltration Trench, A-22" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Planting media depth (dm): 2 to 4 feet (typical)", "page_or_section": "Bioretention Facility Design Criteria, A-35" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum ponding depth (dp): 6 inches (typ.)", "page_or_section": "Bioretention Facility Design Criteria, A-35" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The maximum depth of the permanent pool should not exceed 8 feet (DOEE 2020).", "page_or_section": "Wet Pond Design Criteria, A-67" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "A flow path having a minimum length-to-width ratio of 1.5:1 shall be provided for wet ponds (DOEE 2020).", "page_or_section": "Wet Pond Additional Design Parameters, A-68" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Full DOT-HWYS post-construction BMP manual with explicit WQV/WQFR sizing formulas, Required Treatment Area methodology, and detailed Appendix A BMP designs. Design storm is expressed as 85th-percentile 1-inch depth rather than a standard return-period event.", "fields_not_found": [ "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.stormwaterhawaii.com/wp-content/uploads/2022/07/PC-BMP-Manual_220210-FULL-v2.pdf", "landing_page_url": "https://www.stormwaterhawaii.com/", "retrieved_at": "2026-08-08T01:05:00.000Z", "original_filename": "hawaii-dot-pcbmp.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 96, "ed_drain_time_hours": null, "length_to_width_ratio": 1.5, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:33:01.558Z", "enrich_model": "composer-2.5:run-b263bdbd-82a6-4f4f-a85a-276a89b01746", "enrich_notes": "Volume sizing uses WQV = P × C × AT × 3630 with P = 1 inch (85th-percentile 24-hr runoff depth) and C = 0.95 for impervious highway surfaces when I = 100%. Infiltration BMPs use 48-hr maximum drawdown, FS = 2, and 3 ft minimum separation to seasonally high groundwater. Wet pond permanent pool volume equals full WQV; wet ED splits 50% permanent pool / 50% detention above pool. Pretreatment forebay commonly 10% WQV (25% for sand filter).", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "fl-srwmd-erp-ah2", "processed_at": "2026-08-17T03:19:55.606Z", "detail_url": "https://stormwateratlas.com/fl-srwmd-erp-ah2/", "data_url": "https://stormwateratlas.com/data/manuals/fl-srwmd-erp-ah2.json", "document_metadata": { "jurisdiction_name": "Suwannee River Water Management District (SRWMD)", "jurisdiction_level": "special_district", "state_code": "FL", "document_title": "Environmental Resource Permit Applicant's Handbook Volume II (Design Requirements for Stormwater Treatment and Management Systems)", "version_or_edition": "Effective July 2024", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 100 ], "water_quality_volume_method": "Minimum State water quality treatment requirements are those in statewide ERP Applicant's Handbook Volume I; Volume II requires all systems to recover treatment volumes within 72 hours (retention may use only percolation and evaporation; detention with filtration needs a safety factor of two). Quantity retention in closed basins is post- minus pre-development runoff for the 100-year critical event (max one-day duration). Flood storage recovery: one-half of total volume within seven days and total volume within 30 days after each design storm.", "peak_flow_calculation_method": [ "Pre- and post-development runoff hydrographs with detention/retention routing (stage-storage-discharge)", "Rational Method", "Natural Resources Conservation Service (NRCS) method", "USGS regression equations", "SCS Type II distribution on average antecedent moisture conditions", "Peak Rate Factor (K') method (conservative post-development K'=484)" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention ponds", "Dry detention ponds", "Exfiltration trench systems", "Wet detention ponds", "Swale systems", "Vegetated natural buffers", "Borrow pits and ponds", "Dams and impoundments", "Sensitive karst area BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Suwannee River Water Management District (SRWMD)", "page_or_section": "Title / district handbook" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Florida water management district (ERP Applicant's Handbook Volume II)", "page_or_section": "Chapter 62-330, F.A.C. / district handbook" }, { "field": "document_metadata.state_code", "excerpt": "Incorporated by Reference in Rules 62-330.010 and 40B-400.091, F.A.C.", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "ENVIRONMENTAL RESOURCE PERMIT APPLICANT'S HANDBOOK VOLUME II (DESIGN REQUIREMENTS FOR STORMWATER TREATMENT AND MANAGEMENT SYSTEMS)", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Effective July 2024", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Volume provides specific, detailed information to meet the water quality system and quantity design requirements of stormwater management systems. ... Both Applicant's Handbook Volumes I and II are adopted by reference in Chapter 62-330, F.A.C.", "page_or_section": "Section 1.1.1 Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For projects which serve exclusively agricultural, forest, conservation, or recreational land uses, a design storm with a 10-year, 24-hour rainfall depth with SCS type II distribution ... shall be used. For projects which serve all other land uses, a design storm with 100-year critical duration rainfall depth with SCS type II distribution ... shall be used.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The applicant shall analyze the 100-year frequency (one percent annual chance) analysis of the 1-, 2-, 4-, 8-, and 24-hour durations for all stormwater systems.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "For Alachua, Bradford, Dixie, Gilchrist, Lafayette, Levy, and Taylor counties: Frequency (years) ... 10 ... 25 ... 100", "page_or_section": "Appendix B – Design Storms" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All stormwater management systems must be designed to provide minimum State water quality treatment requirements as set forth in Applicant's Handbook Volume I.", "page_or_section": "Section 4.3 State Water Quality Standards" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "All stormwater management systems shall be designed to recover treatment volumes within 72 hours. For retention systems, only percolation and evaporation may be used to reduce storage and treatment volumes in the system.", "page_or_section": "Section 4.4 Recovery" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The required retention volume is the post-development runoff volume less the pre-development runoff volume for the 100-year critical event with a maximum duration of one day.", "page_or_section": "Section 3.3 Discharge Rates and Volumes (closed basin)" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "One-half of the total volume within seven days following the end of each design storm event, and 2. The total volume within 30 days following the end of each design storm event.", "page_or_section": "Section 3.4 Recovery" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "There are several equations available for calculating discharge including, but not limited to, the Rational Method, Natural Resources Conservation Service (NRCS) method, and USGS regression equations.", "page_or_section": "Section 3.3.1 Methodologies for Calculating Discharge" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "A peak discharge analysis typically consists of generating pre-development and post-development runoff hydrographs, routing the post-development hydrograph through a detention or retention basin, and sizing an overflow structure to control post-development discharges at or below pre-development discharge.", "page_or_section": "Section 3.3.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Peak Rate Factor reflects the effect of watershed storage on the hydrograph shape ... The most conservative approach is to use a K' = 484 for post-development.", "page_or_section": "Section 3.3.1" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "a design storm with a 10-year, 24-hour rainfall depth with SCS type II distribution falling on average antecedent moisture conditions shall be used.", "page_or_section": "Section 3.2 Design Storms" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The Best Management Practices (BMP)s below are the most frequently used BMPs in this District.", "page_or_section": "Part V – Best Management Practices" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5.1 Retention Pond ... 5.2 Dry Detention Pond ... 5.3 Exfiltration Trench Systems ... 5.4 Wet Detention Pond ... 5.5 Swale System ... 5.6 Vegetated Natural Buffers ... 5.7 Borrow Pits and Ponds ... 5.8 Dams and Impoundments ... 5.9 Sensitive Karst Area", "page_or_section": "Table of Contents / Part V" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Volume II requires all systems to recover treatment volumes within 72 hours", "page_or_section": "Atlas context (SRWMD ERP AH Vol II summary)" }, { "field": "practice_mentions.wet_pond", "excerpt": "Wet detention systems are permanently wet ponds which are designed to slowly release collected stormwater runoff through an outlet structure.", "page_or_section": "5.4.1 Description, page 26" }, { "field": "practice_mentions.wet_pond", "excerpt": "The permanent pool shall be sized to provide at least a 14-day residence time based upon average wet season rainfall", "page_or_section": "5.4.3 Permanent Pool, page 26" }, { "field": "practice_mentions.swale", "excerpt": "Swales shall be used for water quality treatment with a maximum slope of three-to-one (3:1)", "page_or_section": "5.7.2 Criteria, page 11" }, { "field": "practice_mentions.extended_detention", "excerpt": "5.2 Dry Detention Pond Design Criteria and Guidelines", "page_or_section": "PART V – BEST MANAGEMENT PRACTICES, page 3" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "5.3 Exfiltration Trench Systems Design Criteria and Guidelines", "page_or_section": "PART V – BEST MANAGEMENT PRACTICES, page 3" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Canonical SRWMD ERP AH Vol II special_district record. City proxy gainesville-fl remains for municipal map coverage.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "http://www.srwmd.state.fl.us/DocumentCenter/View/19233", "landing_page_url": "https://www.srwmd.state.fl.us/", "retrieved_at": "2026-08-11T18:38:36.245Z", "original_filename": "fl-srwmd-erp-ah2.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "infiltration_trench", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:17:26.720Z", "enrich_model": "composer-2.5:run-0be34057-96bd-44c2-9124-1ab00879cdf3", "enrich_notes": "Corpus chunks are largely table-of-contents; substantive criteria appear in partial BMP sections. WQv depth is referenced to statewide ERP Applicant's Handbook Volume I, not numerically stated here. Wet detention permanent pool sizing uses 14-day residence time (wet-season rainfall basis); maximum pool depth sentence is truncated in excerpt. Sensitive karst areas require 3 ft unconsolidated soil above limestone (36 in) and max 10 ft vertical staging for wet ponds from SHGWT to design high water—not mapped to canonical SHWT separation field. Road swale note gives 3:1 maximum side slope, not longitudinal slope percent.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tahoe-trpa-bmp", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tahoe-trpa-bmp/", "data_url": "https://stormwateratlas.com/data/manuals/tahoe-trpa-bmp.json", "document_metadata": { "jurisdiction_name": "Tahoe Regional Planning Agency (Lake Tahoe Region)", "jurisdiction_level": "special_district", "state_code": "CA", "document_title": "TRPA Best Management Practices Handbook", "version_or_edition": "May 2014", "adoption_or_effective_date": "2014-05-01", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 20, 100 ], "water_quality_volume_method": "Parcel-based infiltration BMPs are sized to contain and infiltrate runoff from impervious surfaces for the 20-year return period, 1-hour duration design storm (approximately 1 inch in 1 hour). TRPA regulations require containment of that volume from impervious areas; the NRCS BMP Calculation Spreadsheet multiplies 20-yr/1-hr intensity by each impervious surface area. Public right-of-way BMPs use pollutant load reduction modeling tools rather than a single WQv formula.", "peak_flow_calculation_method": [ "Rational Method", "NRCS BMP Calculation Spreadsheet", "Load Reduction Planning Tool (LRPT)", "Hydrologic Modeling System (HMS)", "Pollutant Load Reduction Model (PLRM)" ], "required_hydrologic_hydraulic_software": [ "NRCS BMP Calculation Spreadsheet", "Load Reduction Planning Tool (LRPT)", "Hydrologic Modeling System (HMS)", "Pollutant Load Reduction Model (PLRM)", "HSPF / LSPC", "Storm Water Management Model (SWMM)" ], "approved_bmp_categories": [ "Hydrologic Source Control — Pervious Pavement", "Hydrologic Source Control — Infiltration Basin", "Hydrologic Source Control — Infiltration Trench", "Hydrologic Source Control — Subsurface Infiltration System", "Hydrologic Source Control — Rain Barrel and Cistern", "Hydrologic Source Control — Rain Garden", "Hydrologic Source Control — Filter Strip", "Pollutant Source Control — Abrasive and Deicer Management", "Pollutant Source Control — Street Sweeping", "Pollutant Source Control — Snow Storage", "Pollutant Source Control — Vegetated Slope Stabilization", "Pollutant Source Control — Waste and Hazardous Material Management", "Stormwater Collection — Culvert, Curb and Gutter, Storm Drain", "Stormwater Collection — Rock Lined and Vegetated Swale", "Stormwater Collection — Check Dams", "Stormwater Treatment — Wet Basin", "Stormwater Treatment — Bioswale", "Stormwater Treatment — Dry Basin", "Stormwater Treatment — Drop Inlet Insert", "Stormwater Treatment — Hydrodynamic Separator", "Stormwater Treatment — Media Filter", "Stormwater Treatment — Sediment Trap", "Temporary Construction BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "TAHOE REGIONAL PLANNING AGENCY", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The Tahoe Regional Planning Agency (TRPA) Best Management Practices (BMP) Handbook provides technical and planning guidance to landowners, private businesses, agencies, and jurisdictions for water quality improvement projects.", "page_or_section": "Preface" }, { "field": "document_metadata.document_title", "excerpt": "Best Management Practices handbook", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The design storm for parcel-based BMPs at Lake Tahoe is the 20-yr/1-hr rainfall event, approximately 1 inch of water falling in 1 hour.", "page_or_section": "Introduction, Page 16" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "events of interest (e.g., the 1 percent annual chance or 100-year peak flow may be estimated from a gaging station record", "page_or_section": "Chapter 1: Urban Hydrology, Section 1.2.4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "TRPA regulations, which require containment of the stormwater runoff volume generated by a 20-year return period, 1-hour duration \"design storm\" from impervious surfaces on a parcel.", "page_or_section": "Chapter 1, Section 1.3.3.2 NRCS BMP Calculation Spreadsheet" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The Design Storm used for infiltration BMPs on small residential sites is the 20-yr/1-hr storm, approximately 1\"/hr.", "page_or_section": "Chapter 3, Section 3.5.3 Hydrologic Source Control" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "application of the well-known \"Rational Method\" involves derivation of a runoff coefficient based on measurable land use conditions", "page_or_section": "Chapter 1, Section 1.2.4" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "1.3.3.3 Rational Method ... 1.3.3.4 Load Reduction Planning Tool (LRPT) ... 1.3.3.5 Hydrologic Modeling System (HMS) ... 1.3.3.6 Pollutant Load Reduction Model (PLRM) ... 1.3.3.7 HSPF and LSPC ... 1.3.3.8 Storm Water Management Model (SWMM)", "page_or_section": "Chapter 1 Table of Contents" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "4.1 Hydrologic Source Control ... 4.2 Pollutant Source Control ... 4.3 Stormwater Collection and Conveyance ... 4.4 Stormwater Treatment ... 4.5 Temporary BMPs for Construction", "page_or_section": "Chapter 4: BMP Toolkit Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the 20-yr/1-hr rainfall event, approximately 1 inch of water falling in 1 hour", "page_or_section": "Introduction, page 15 (tahoe-trpa-bmp-c0050)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "For a small site this will be based on the 20-yr/1-hr storm.", "page_or_section": "CHAPTER 2 Site Analysis, page 2-25 (tahoe-trpa-bmp-c0126)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The bottom of infiltration trenches or drywells shall be a minimum of one foot above the seasonal high water table.", "page_or_section": "CHAPTER 2 Site Analysis, page 2-3 / Code 60.4.6.A.1 (tahoe-trpa-bmp-c0106)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Depth to seasonal high groundwater, bedrock, or a restrictive layer shall be at least 1 foot below the bottom of the trench.", "page_or_section": "4.1-c Infiltration Trench, page 19 (tahoe-trpa-bmp-c0169)" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "depth to seasonal high groundwater, bedrock, or any impermeable layer is at least 3 feet below the underlying base course", "page_or_section": "4.1-a Pervious Pavement DESIGN CONSIDERATIONS (tahoe-trpa-bmp-c0157)" }, { "field": "practice_mentions.bioretention", "excerpt": "Alternative Names: Small Vegetated Basin, Infiltration Garden, Bio-Retention Garden", "page_or_section": "4.1-f Rain Garden, page 37 (tahoe-trpa-bmp-c0180)" }, { "field": "practice_mentions.extended_detention", "excerpt": "Alternative Names: Dry Pond, Extended Detention Basin, Detention Basin, Sediment Basin", "page_or_section": "4.4-c Dry Basin, page 17 (tahoe-trpa-bmp-c0317)" }, { "field": "design_parameters.fields_not_found.design_infiltration_rate_in_per_hr", "excerpt": "Not appropriate for soils with infiltration rates less than 1\"/hr", "page_or_section": "4.1-b Infiltration Basin / 4.1-f Rain Garden (threshold only, not design rate)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Bi-state Lake Tahoe Region (CA/NV) TRPA BMP Handbook. state_code CA used for atlas mapping; jurisdiction spans both California and Nevada shorelines. Large combined PDF (736 pages); prepared text truncated at 750k chars. Individual chapters on tahoebmp.org may be newer (e.g., Ch5 Dec 2024) than the bundled complete PDF (May 2014). Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "document_metadata.version_or_edition" ] }, "source": { "document_url": "https://tahoebmp.org/Documents/BMPHandbook/BMP_Handbook.pdf", "landing_page_url": "https://tahoebmp.org/bmphandbook.aspx", "retrieved_at": "2026-08-12T22:44:57.055Z", "original_filename": "tmp-tahoe-trpa-bmp.json" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": 12, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "swale" ], "enriched_at": "2026-08-13T10:18:25.406Z", "enrich_model": "composer-2.5:run-9b858480-071e-4e43-98b6-c3f48a26705e", "enrich_notes": "Parcel BMP sizing uses 20-yr/1-hr storm (~1 in in 1 hr), not a separate WQv label. Infiltration BMPs cite Ksat slow below 1 in/hr and CHP/percolation for site design; no single handbook design infiltration rate. SHWT: 1 ft minimum below bottom of infiltration trenches or drywells (TRPA Code 60.4.6.A.1). Vegetated swales for site slopes ≤5%; not extracted as swale longitudinal slope design value.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tarrant-county-tx", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tarrant-county-tx/", "data_url": "https://stormwateratlas.com/data/manuals/tarrant-county-tx.json", "document_metadata": { "jurisdiction_name": "Tarrant County", "jurisdiction_level": "county", "state_code": "TX", "document_title": "iSWM Technical Manual — Site Development Controls (NCTCOG)", "version_or_edition": "Revised 04/10", "adoption_or_effective_date": null, "last_revised_date": "2010-04-01", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": "Structural controls sized to treat the Water Quality Volume (WQv); primary performance goal approximately 70–80% TSS removal (Primary TSS). Integrated design also addresses streambank protection volume (SPv) and flood control. Controls may be online or offline diverting WQv to treatment.", "peak_flow_calculation_method": [ "Water Quality Volume (WQv)", "Streambank Protection Volume (SPv)", "Flood control / detention routing" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Enhanced swales / grass channels", "Filter strips", "Organic filters / sand filters", "Planter boxes", "Infiltration trenches / drywells / soakage trenches", "Stormwater ponds / wetlands", "Dry detention / extended detention", "Underground detention", "Permeable pavement / porous concrete", "Green roofs", "Rainwater harvesting" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "iSWM Technical Manual Site Development Controls — NCTCOG regional guidance used in Tarrant County", "page_or_section": "Coverage note" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Tarrant County", "page_or_section": "Coverage note" }, { "field": "document_metadata.state_code", "excerpt": "North Central Texas Council of Governments", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "iSWMTM Technical Manual Site Development Controls", "page_or_section": "Title" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised 04/10", "page_or_section": "Footer" }, { "field": "document_metadata.last_revised_date", "excerpt": "Revised 04/10", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "iSWM Online Technical Manual referenced by community iSWM Criteria Manuals", "page_or_section": "NCTCOG iSWM" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Ability to treat the Water Quality Volume (WQv) ... 70% TSS removal performance goal", "page_or_section": "§1.2 / structural control selection" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Water Quality; Streambank Protection; Flood Control", "page_or_section": "§1.2 Integrated Design Focus Areas" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "8.0 Inlets 9.0 Pipe Systems 10.0 Dry Detention / Extended Detention Dry Basins 11.0 Multi-Purpose Detention Areas 12.0 Underground Detention 13.0 Filter Strip 14.0 Organic Filter 15.0 Planter Boxes 16.0 Sand Filters 17.0 Underground Sand Filter 18.0 Gravity (Oil Grit) Separato", "page_or_section": "p. 1" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "tf = design filter bed drain time (days) (2.0 days or 48 hours is recommended maximum)", "page_or_section": "Bioretention SD-37, page 49" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Given that a bioretention facility is typically designed to completely drain over 48 hours", "page_or_section": "Bioretention SD-31, page 43" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "this method should be used only for bioretention areas, filter facilities, and infiltration trenches where the drawdown time is ≥ 24 hours", "page_or_section": "Overview SD-26, page 38" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Minimum Depth to Water Table – A separation distance of 2 feet recommended between the bottom of the bioretention facility and the elevation of the seasonally high water table.", "page_or_section": "Bioretention SD-32, page 44" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "df = filter bed depth (2.5 feet minimum)", "page_or_section": "Bioretention SD-37, page 49" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "hf = average height of water above filter bed (ft) (typically 3 inches, which is half of the 6-inch ponding depth)", "page_or_section": "Bioretention SD-37, page 49" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate > 0.5 inch/hr", "page_or_section": "Table 5.1.3-1 Structural Control Screening Matrix, page 23" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Limit maximum normal pool depth to about 4 feet (dugout)", "page_or_section": "Table 5.1.3-1 Structural Control Screening Matrix, page 23" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "the water quality orifice is sized to release this extended detention volume in 24 hours", "page_or_section": "Stormwater Ponds SD-160, page 172" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "released over a period of 24 hours", "page_or_section": "Stormwater Wetlands SD-194, page 206" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Assume a roughly 2 to 1 rectangular shape.", "page_or_section": "Stormwater Control Design Examples SD-237, page 249" }, { "field": "design_parameters.wetland_detention_hours", "excerpt": "part of the water quality treatment volume is provided as extended detention above the surface of the marsh and released over a period of 24 hours", "page_or_section": "Stormwater Wetlands SD-194, page 206" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "County coverage via NCTCOG iSWM Site Development Controls technical manual. Local Tarrant/iSWM Criteria Manual adoption details not separately ingested.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "design_criteria.design_storm_return_periods_years", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://iswm.nctcog.org/Documents/technical_manual/Site_Development_Controls_4-2010b.pdf", "landing_page_url": "https://www.iswm.nctcog.org/technical-manual.html", "retrieved_at": "2026-08-10T09:20:00.000Z", "original_filename": "tarrant-county-tx.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 30, "bioretention_ponding_depth_inches": 6, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 24, "length_to_width_ratio": 2, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:20:25.661Z", "enrich_model": "composer-2.5:run-fa0ac926-cfa2-473c-a681-1f15e6ecbbda", "enrich_notes": "NCTCOG iSWM Site Development Controls; WQv sizing referenced but rainfall depth for WQv not stated in excerpts. Bioretention filter drain uses k=0.5 ft/day in examples (not mapped to in/hr field). Pond/wetland aquifer notes cite 2–4 ft SHWT separation in places; bioretention cites 2 ft recommended. ED release commonly 24 h; cold-water/stream habitat cases may use 12 h WQv-ED. Proprietary BMPs require manufacturer data and independent third-party verification without naming TAPE/NJCAT.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "permeable_pavement_storage_depth_inches", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tn-tdot-drainage", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tn-tdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/tn-tdot-drainage.json", "document_metadata": { "jurisdiction_name": "Tennessee", "jurisdiction_level": "state", "state_code": "TN", "document_title": "TDOT Drainage Manual Chapter 7", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 50 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "TDOT Drainage Manual Chapter 7", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "quency Criteria See Section Gutter Flow 10-year1,2 Spread on Roadway 7.03.2 Inlet Spacing 10-year1,2 Spread on Roadway 7.03.3.7", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "gutter is typically evaluated using the Rational Method (see Chapter 4 of this Manual) and the spread is determined by examining", "page_or_section": null } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. TDOT Drainage Manual Chapter 7 — Storm Drainage Systems Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.tn.gov/content/dam/tn/tdot/engineering-production-support/documents/drainage_manual/DM-Chapter_07.pdf", "landing_page_url": "https://www.tn.gov/tdot/state-engineering-technical-training/production-support/design-standards/drainage-manual.html", "retrieved_at": "2026-08-11T17:59:10.596Z", "original_filename": "tn-tdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T10:21:33.769Z", "enrich_model": "composer-2.5:run-0a77fe9d-eb8c-4c8d-9a33-5df3d3b18450", "enrich_notes": "Provided excerpts are TDOT Drainage Manual Chapter 7 (Storm Drainage Systems): roadway gutters, inlets, storm sewers, catch basins/manholes, and design storm frequencies (e.g., Table 7-1: 10-year gutter/inlet/pipe sizing; 50-year at sags/freeways/cross drains). Median/side ditch hydraulics are referenced to Chapter 5. No water-quality volume (WQv) method or canonical stormwater SCM/BMP design criteria appear in this corpus.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tn-state", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tn-state/", "data_url": "https://stormwateratlas.com/data/manuals/tn-state.json", "document_metadata": { "jurisdiction_name": "Tennessee Department of Environment and Conservation", "jurisdiction_level": "state", "state_code": "TN", "document_title": "Tennessee Permanent Stormwater Management and Design Guidance Manual", "version_or_edition": "First Edition", "adoption_or_effective_date": "2014-12-01", "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 5, 10, 25, 100 ], "water_quality_volume_method": "Infiltrate, evapotranspirate, harvest and/or use the first inch of every rainfall event preceded by 72 hours of dry weather.", "peak_flow_calculation_method": [ "Rational Method", "SCS Curve Number Approach" ], "required_hydrologic_hydraulic_software": [ "Tennessee Runoff Reduction Assessment Tool (TNRRAT)" ], "approved_bmp_categories": [ "Dry Detention", "Wet Ponds", "Vegetated Swale (Water Quality Swale)", "Managed Vegetated Areas (Urban Forest, Grassland and Riparian Buffers)", "Filter Strips", "Bioretention", "Urban Bioretention", "Infiltration Areas (Impervious Area Disconnection)", "Permeable Pavement", "Green Roofs", "Rainwater Harvesting", "Stormwater Treatment Wetlands", "Manufactured/Proprietary Treatment Devices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Tennessee Department of Environment and Conservation", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Tennessee Department of Environment and Conservation\nDivision of Water Resources", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Tennessee Permanent Stormwater Management and Design Guidance Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "maintained to infiltrate, evapot the first inch of every rainfall event preceded by 72 hou of rainfall must be 100% managed with no stormwater site design and assessment purposes, this manual expre component and an overall volume, as discussed in deta Limitations to the applic", "page_or_section": "p. 23" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "December 2014", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "prepared by the Tennessee Department of Environment and Conservation, Division of Water Resources", "page_or_section": "Acknowledgements" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Typically, a 10-year or 25-year return design storm is used to size storm sewer systems... Similarly, a 2-year or 5-year return design storm is used to protect from downstream... Additionally, a 100-year return design storm is used to protect from downstream flooding", "page_or_section": "Chapter 4, Section 4.5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "designed, built, and maintained to infiltrate, evapotranspirate, harvest and/or use, the first inch of every rainfall event preceded by 72 hours of dry weather.", "page_or_section": "Chapter 2, Section 2.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "SCS Curve Number Approach (Hann et al., 1994)", "page_or_section": "Chapter 6, Section 6.1" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Tennessee Runoff Reduction Assessment Tool (TNRRAT)", "page_or_section": "Chapter 6, Section 6.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "5.4.1 Dry Detention\n5.4.2 Wet Ponds\n5.4.3 Vegetated Swale (Water Quality Swale)\n5.4.4 Managed Vegetated Areas\n5.4.5 Filter Strips\n5.4.6 Bioretention\n5.4.6a Urban Bioretention\n5.4.7 Infiltration Areas\n5.4.8 Permeable Pavement\n5.4.9 Green Roofs\n5.4.10 Rainwater Harvesting\n5.4.11 Stormwater Treatment Wetlands\n5.4.12 Manufactured/Proprietary Treatment Devices", "page_or_section": "Chapter 5, Section 5.4" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "A Dry Detention Basin relies on maximum 24-hour detention of stormwater runoff after each rain event.", "page_or_section": "Chapter 1, Table 1.2 overview (tn-state-c0020)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "An Extended Detention Basin relies on 72-hour detention of stormwater runoff after each rain event.", "page_or_section": "Chapter 1, Table 1.2 overview (tn-state-c0020)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A separation distance of 2 feet is required between the excavated Bioretention area and the seasonally", "page_or_section": "5.4.6 Bioretention, Depth to Water Table (tn-state-c0176)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Depth: 2 feet to water table / bedrock", "page_or_section": "5.4.6 Bioretention, Site Constraints (tn-state-c0174)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Min. filter media depth: 18-24 inches. Recommended maximum: 36 inches", "page_or_section": "5.4.6 Bioretention, Key Design Criteria (tn-state-c0174)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The standard minimum filter should be 24 inches for bioretention cells, and 18 to 24 inches for rain gardens or micro-", "page_or_section": "5.4.6 Bioretention, Depth (tn-state-c0179)" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding depth: 6-12 inches", "page_or_section": "5.4.6 Bioretention, Key Design Criteria (tn-state-c0174)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Media permeability: ≤ 0.5in/h or needs underdrain", "page_or_section": "5.4.6 Bioretention, Site Constraints (tn-state-c0174)" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "underdrain is needed if the measured permeability of the underlying ... 0.5 inches per hour.", "page_or_section": "5.4.6 Bioretention, Soils (tn-state-c0176)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Length of shortest flow path/length: 0.3", "page_or_section": "5.4.6 Bioretention, Key Design Criteria (tn-state-c0174)" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "A minimum slope of 0.5% must be maintained to ensu", "page_or_section": "Appendix B, Grass Channel (tn-state-c0313)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "All required properties were successfully extracted from the text. The document is the official state manual for Tennessee, published by TDEC in December 2014. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "document_metadata.state_code" ] }, "source": { "document_url": "https://lewisburgtn.gov/wp-content/uploads/2022/11/Permanent-Stormwater-Management-Design-Guidance-Manual.pdf", "landing_page_url": "https://www.tn.gov/environment/program-areas/wr-water-resources/stormwater.html", "retrieved_at": "2026-08-07T11:27:05.531Z", "original_filename": "tn-state.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 24, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 72, "length_to_width_ratio": 0.3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:21:08.950Z", "enrich_model": "composer-2.5:run-f423f3a0-2b59-4339-9ea9-09ddd3ae70cd", "enrich_notes": "TN manual (Dec 2014): dry detention cites 24 h max detention; extended detention 72 h. Bioretention filter media min 18–24 in (18 used as minimum), ponding 6–12 in (range only). Seasonal high water table separation 2 ft (24 in) for bioretention. Native/filter media permeability threshold 0.5 in/hr triggers underdrain. Shortest flow-path ratio 0.3 in bioretention key criteria. Grass channel karst appendix minimum longitudinal slope 0.5%.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tx-txdot-hydraulic", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tx-txdot-hydraulic/", "data_url": "https://stormwateratlas.com/data/manuals/tx-txdot-hydraulic.json", "document_metadata": { "jurisdiction_name": "Texas", "jurisdiction_level": "state", "state_code": "TX", "document_title": "TxDOT Hydraulic Design Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-RAS" ], "required_hydrologic_hydraulic_software": [ "HEC-RAS" ], "approved_bmp_categories": [ "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "TxDOT Hydraulic Design Manual", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "0% 0.50 2-year 20% 0.20 5-year 10% 0.10 10-year 4% 0.04 25-year 2% 0.02 50-year 1% 0.01 100-year While AEP, expressed as a perc", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": ". . . . . . . . . . . 4-45 Section 12: Rational Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin, Retention Basin", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "Measures intended to mitigate storm water quantity and quality problems are termed “best management practices” (BMPs). These measures include detention and retention ponds which delay storm water flow and trap sediment", "page_or_section": "Chapter 13, Section 1, Hydraulic Design Manual 13-2" }, { "field": "practice_mentions.extended_detention", "excerpt": "storm water detention and retention systems to reduce peak runoff rates and improve water quality", "page_or_section": "Chapter 13, Section 1, Hydraulic Design Manual 13-2" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Alternatively, a permeable asphalt surface may be considered under load conditions that warrant its use. Typically, the asphalt layer lies on top of an aggregate drainage layer", "page_or_section": "Chapter 15, Storm Surge and Drawdown Protection, Hydraulic Design Manual 15-84" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "f = infiltration capacity (in./hr.) Ks = saturated hydraulic conductivity (permeability) (in./hr.)", "page_or_section": "Chapter 4, Section 13 Hydrograph Method, Green and Ampt, Hydraulic Design Manual 4-99" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. TxDOT Hydraulic Design Manual (revised Sept 2019) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://www.txdot.gov/content/dam/txdotoms/des/hyd/hyd.pdf", "landing_page_url": "https://www.txdot.gov/manuals/des/hyd/index.html", "retrieved_at": "2026-08-11T17:59:10.553Z", "original_filename": "tx-txdot-hydraulic.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention", "permeable_pavement" ], "enriched_at": "2026-08-13T10:26:44.615Z", "enrich_model": "composer-2.5:run-eead6b4f-6bb4-4e84-a95b-58457ab03331", "enrich_notes": "Corpus is TxDOT Hydraulic Design Manual (9/2019) hydrology, storm drains, and Ch. 13 storm water management—not detailed SCM sizing. BMPs cited generically (detention/retention ponds, sediment controls). Green-Ampt defines Ks and f in in./hr. without a single design infiltration criterion. Coastal section discusses permeable asphalt and aggregate drainage layers without storage depth. No WQv depth, drawdown times, bioretention/swale/green-roof dimensions, or MTD verification programs in supplied excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "tx-edwards-rg348", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/tx-edwards-rg348/", "data_url": "https://stormwateratlas.com/data/manuals/tx-edwards-rg348.json", "document_metadata": { "jurisdiction_name": "Texas Commission on Environmental Quality", "jurisdiction_level": "state", "state_code": "TX", "document_title": "Complying with the Edwards Aquifer Rules — Technical Guidance on Best Management Practices", "version_or_edition": "RG-348, Revised July 2005 (errata March 28, 2009; addendum January 20, 2017)", "adoption_or_effective_date": "2005-07-01", "last_revised_date": "2017-01-20", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 100 ], "water_quality_volume_method": "Permanent BMPs must remove at least 80% of the increase in TSS load from development; capture volume is sized from annual pollutant load (L = A × P × Rv × C × 0.226) and BMP-specific TSS removal efficiency.", "peak_flow_calculation_method": [ "Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Retention/Irrigation", "Extended Detention Basin", "Grassy Swales", "Vegetative Filter Strips", "Sand Filter Systems", "AquaLogic Cartridge Filter System", "Wet Basins", "Constructed Wetlands", "Bioretention", "Permeable Concrete", "Wet Vaults", "Silt Fence", "Sediment Basins", "Vegetative Buffers", "Inlet Protection" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Texas Commission on Environmental Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "The Edwards Aquifer rules are an effective mechanism we can use to protect this valuable resource. Found in Title 30 Texas Administrative Code Chapter 213", "page_or_section": "Preface" }, { "field": "document_metadata.state_code", "excerpt": "Texas Commission on Environmental Quality", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Complying with the Edwards Aquifer Rules Technical Guidance on Best Management Practices", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "RG-348 Revised July 2005 Includes Errata Sheet (March 28, 2009) and Addendum Sheet (Jan. 20, 2017).", "page_or_section": "Title Page" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "Revised July 2005", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "Addendum Sheet (Jan. 20, 2017).", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The Edwards Aquifer Rules (30 TAC Chapter 213) regulate activities having the potential for polluting the Edwards Aquifer", "page_or_section": "Chapter 3.1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Structural BMPs located in the floodplain should be constructed with the wall elevation of any basins or ponds higher than the elevation of the 100 year flood at that location.", "page_or_section": "Chapter 3.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The selected BMP or combination of BMPs must reduce the increase in total suspended solids (TSS) load associated with development by at least 80%.", "page_or_section": "Chapter 3.1" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Equation 3.1 L = A× P × Rv × C × 0.226", "page_or_section": "Section 3.3.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The runoff rate from the tributary area is calculated using the rational method as shown in Equation 3.4.", "page_or_section": "Section 3.3.2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Retention/Irrigation 100 ... Extended Detention Basin 75 ... Grassy Swales 70 ... Vegetative Filter Strips 85 ... Sand Filter Systems 89 ... Bioretention 89 ... Wet Basins 93 ... Constructed Wetlands 93 ... Permeable Concrete 89-100", "page_or_section": "Table 3-1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "1.4.3 Silt Fence ... 1.4.13 Sediment Basins ... 1.4.10 Vegetative Buffers ... 1.4.11 Inlet Protection", "page_or_section": "Table of Contents, Chapter 1" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table should be at least 4 feet below the surface.", "page_or_section": "3.2.4 Grassy Swales / page 3-11" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The outflow structure should be sized to allow for complete drawdown of the water quality volume in 48 hours.", "page_or_section": "3.4.5 Extended Detention Basins / page 3-49" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum length to width ratio should be 1.0. Higher ratios are recommended.", "page_or_section": "3.4.9 Wet Basins / page 3-66" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "the channel slope should be at least 0.5% and no greater than 2.5%", "page_or_section": "Errata 3.4.5 Grassy Swales / page 326" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "From Table 3-5, one can see that 0.86 corresponds to a rainfall depth of 1.46 inches.", "page_or_section": "6.3.2 example / page 318" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "infiltration rates of less than 0.5 inch/hour", "page_or_section": "3.2.1 Introduction / page 3-5" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "TCEQ RG-348 technical guidance implementing Edwards Aquifer rules (30 TAC Chapter 213) for eight central Texas counties. Primary permanent BMP list from Table 3-1; temporary construction BMPs from Chapter 1 included where commonly cited.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.tceq.texas.gov/downloads/publications/rg/complying-with-the-edwards-aquifer-rules-rg-348.pdf", "landing_page_url": "https://www.tceq.texas.gov/publications/rg/rg-348", "retrieved_at": "2026-08-08T00:52:06.514Z", "original_filename": "tx-edwards-rg348.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 1, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 2.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:26:15.710Z", "enrich_model": "composer-2.5:run-fce11202-f4af-4db8-9cf5-e1f96daa960a", "enrich_notes": "WQV rainfall depth is site-specific via Table 3-5 fraction F (examples: 1.46 in, 2.60 in); storage sized with 20% sediment allowance. Infiltration basins/trenches excluded in most of the area; sites with infiltration <0.5 in/hr precluded. Wet vault sizing uses 1.1 in/hr rainfall intensity (not WQV depth).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "cary-nc", "processed_at": "2026-08-17T03:19:55.598Z", "detail_url": "https://stormwateratlas.com/cary-nc/", "data_url": "https://stormwateratlas.com/data/manuals/cary-nc.json", "document_metadata": { "jurisdiction_name": "Town of Cary", "jurisdiction_level": "municipality", "state_code": "NC", "document_title": "NCDEQ Stormwater Design Manual (Town uses State MDC; LDO 4.4.6)", "version_or_edition": "Revised: 1-3-2017", "adoption_or_effective_date": "2017-01-03", "last_revised_date": "2017-01-03", "relationship_to_state_manual": "adopts_state_manual_directly" }, "design_criteria": { "design_storm_return_periods_years": [ 10 ], "water_quality_volume_method": "Combined design volume of all SCMs must handle the required storm depth for the applicable stormwater program (depth varies by rule). Example: Rule 15A NCAC 02H .1021(6) requires a one-inch storm depth for runoff treatment in non-coastal HQW and ORW management zones. Design volume accounts for build-out runoff from all surfaces draining to the system; off-site drainage may be bypassed. Volume calculation methods are in Part B of the full manual (not in this chapter).", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Infiltration systems", "Bioretention cells", "Permeable pavement", "Vegetated swales", "Level spreader-filter strips", "Berms", "SCM-specific devices per Rules 15A NCAC 02H .1051–.1062 (Part C)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "--- page 2 --- NCDEQ Stormwater BMP Manual ________________________________________________________________________________________________________ C-0. MDC for all SCMs 2 Revised: 1-3-2017 GENERAL MDC 1. SIZING. The design volume of SCMs shall take into", "page_or_section": "p. 2" }, { "field": "document_metadata.state_code", "excerpt": "North Carolina", "page_or_section": "NCDEQ" }, { "field": "document_metadata.document_title", "excerpt": "NCDEQ Stormwater Design Manual — C-0. Minimum Design Criteria for all SCMs", "page_or_section": "C-0" }, { "field": "document_metadata.version_or_edition", "excerpt": "Revised: 1-3-2017", "page_or_section": "C-0" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "The outlets of SCMs shall be designed so that they do not cause erosion immediately downslope of the discharge point during the peak flow from the 10-year storm event as shown by engineering calculations.", "page_or_section": "GENERAL MDC 4: EROSION PROTECTION, Page 3" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The combined design volume of all SCMs on the project shall be sufficient to handle the required storm depth... Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING, Page 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Some SCMs that allow water to infiltrate include: infiltration systems, bioretention cells, permeable pavement, and depending upon native soils, vegetated swales, level spreader-filter strips, and berms.", "page_or_section": "GENERAL MDC 2: CONTAMINATED SOILS, Page 2" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Every SCM shall follow the applicable device specific MDC pursuant to Rules .1051 through .1062 of this Section.", "page_or_section": "GENERAL MDC 13, Page 6" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Rule 15A NCAC 02H .1021(6) requires that for projects designed to achieve runoff treatment, the required storm depth is one inch for non-coastal HQW and ORW management zones.", "page_or_section": "GENERAL MDC 1. SIZING., page 2" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Cary adopts NCDEQ Stormwater Design Manual MDC for SCM design; local LDO/engineering details not separately ingested. Pipeline excerpt repair removed 4 unlocated citation(s).", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.jurisdiction_level", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "document_metadata.relationship_to_state_manual" ] }, "source": { "document_url": "https://www.deq.nc.gov/energy-mineral-and-land-resources/stormwater/bmp-manual/c-0-mdc-all-scms/download", "landing_page_url": "https://www.carync.gov/services-publications/water-sewer/stormwater-management/watershed-protection-and-nitrogen-control", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "cary-nc.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "infiltration_basin", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T07:46:45.727Z", "enrich_model": "composer-2.5:run-6d28c03d-f9ae-48dc-9fd2-178993974706", "enrich_notes": "Corpus is NCDEQ C-0 General MDC only (pages 2–7); SCM-specific numeric criteria are in Part C (Rules .1051–.1062), not in excerpts. One-inch storm depth cited as example for Rule 15A NCAC 02H .1021(6) runoff treatment in non-coastal HQW/ORW zones; required depth varies by program rule.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "prescott-valley-az", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/prescott-valley-az/", "data_url": "https://stormwateratlas.com/data/manuals/prescott-valley-az.json", "document_metadata": { "jurisdiction_name": "Town of Prescott Valley", "jurisdiction_level": "municipality", "state_code": "AZ", "document_title": "Uniform Drainage Policies and Standards Manual", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": "2025-02-10", "relationship_to_state_manual": "independent", "issuing_agency_category": null }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": "First flush: retain or treat the first 0.5 inches of direct runoff from a storm event; green infrastructure/LID in Appendix B may meet requirements if equivalent volume and performance are achieved.", "peak_flow_calculation_method": [ "Hierarchy: Town Master Drainage Plan, ADMS/ADMPs, or approved flood insurance studies; then adjacent property drainage plans; otherwise procedures in this Manual (Section 6.3)", "Rational Method for peak discharges (areas ≤160 acres, Tc ≤60 min)", "Unit hydrograph method via HEC-HMS with 24-hour frequency storm (PFDS/Table 6-3); Green and Ampt rainfall losses for HMS" ], "required_hydrologic_hydraulic_software": [ "HEC-HMS (most recent version)", "HEC-RAS (most recent version)", "HY-8 (most recent version)", "EPA-SWMM (most recent version)", "FLO-2D (most recent version, or as approved by FEMA for an FIS study)", "XP Storm (most recent version, or as approved by FEMA for an FIS study)" ], "approved_bmp_categories": [ "Best Management Practices (BMP)", "green infrastructure", "low impact development", "stormwater harvesting basins", "sediment traps", "curb openings", "stormwater pollution prevention practices meeting first flush" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Town of Prescott Valley Uniform Drainage Policies and Standards Manual", "page_or_section": "page 21" }, { "field": "document_metadata.document_title", "excerpt": "Uniform Drainage Policies and Standards Manual", "page_or_section": "page 21" }, { "field": "document_metadata.last_revised_date", "excerpt": "WEST Consultants, Inc. 10 10-Feb-25", "page_or_section": "page 21" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "The hydrology for the Town is based on the methods in the Drainage Design Manual for Yavapai County (Yavapai County, 2015).", "page_or_section": "Section 6.3, page 69" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Post-development peak discharges may not exceed pre-development peak discharges for the 2-, 10-, and 100-year storm events for the design of detention basins.", "page_or_section": "Standard 6.9.3, page 164" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "Runoff Coefficients by Storm Frequency 2- to 10-year 25-year 50-year 100-year", "page_or_section": "Table 6-5, page 78" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "All new developments shall make provisions to retain the stormwater runoff from a 100-year, 2-hour duration storm.", "page_or_section": "Standard 6.9.1, page 164" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "a. 10-year: One 12-foot dry lane each direction, and flow depth shall not exceed curb height. b. 100-year: Maximum flow depth between curbs < 8 inches.", "page_or_section": "Standard 6.4.3, page 144" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The minimum level of control for new development at which stormwater pollution prevention practices must be put in place is called the “first flush.” This consists of retaining or treating the first 0.5 inches of direct runoff from a storm event.", "page_or_section": "Policy 3.5.6, page 29" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "These green infrastructure techniques may be used to meet the first flush volume requirements if equivalent volume and performances are achieved.", "page_or_section": "Policy 3.5.6, page 29" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The following is the preferred order of hierarchy for obtaining peak discharges and runoff volumes", "page_or_section": "Policy 3.4.1, page 28" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "peak discharges and runoff volumes shall be calculated in accordance with the procedures in this Manual.", "page_or_section": "Policy 3.4.1, page 28" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Rational Method, as presented herein, can be used to estimate peak discharges... for small, uniform drainage areas that are not larger than 160 acres in size.", "page_or_section": "Section 6.3.3.1, page 72" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Drainage areas that do not meet the above conditions will require the use of the unit hydrograph method implemented through the HEC-HMS Program", "page_or_section": "Section 6.3.3.2, page 73" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The design storm for synthetic unit hydrograph calculation methods shall be a 24-hour duration \"frequency storm\" distribution as defined by the HEC-HMS program.", "page_or_section": "Section 6.3.1, page 69" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "One method shall be used to estimate rainfall losses: the Green and Ampt Method.", "page_or_section": "Section 6.3.4, page 83" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "1D Hydrology – HEC-HMS (most recent version) 1D Hydraulics – HEC-RAS (most recent version), HY-8 (most recent version), and EPA-SWMM (most recent version)", "page_or_section": "Section 6.12, page 175" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "2D Hydrology – HEC-RAS (most recent version). FLO-2D (most recent version, or as approved by FEMA for an FIS study) 2D Hydraulics – HEC-RAS (most recent version). FLO-2D ... XP Storm ... EPA-SWMM", "page_or_section": "Section 6.12, page 175" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Stormwater Pollution Prevention is to be addressed through the use of Best Management Practices (BMP) to the maximum extent practicable", "page_or_section": "Policy 3.5.5, page 29" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The Town encourages the use of green infrastructure and low impact development techniques", "page_or_section": "Policy 3.5.6, page 29" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Street design may also consider green stormwater infrastructure practices including stormwater harvesting basins, sediment traps, and curb openings.", "page_or_section": "Section 3.8, page 33" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": "Corpus is Appendix A excerpts mis-tagged in chunk IDs; hydrology/detention content is clearly from main manual Sections 3–6 and Appendix B. Facility-specific return periods beyond cited standards may exist in uncited sections.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.issuing_agency_category" ] }, "source": { "document_url": "https://www.prescottvalley-az.gov/Documents/Departments/Public%20Works/TOPV%20DrainagePoliciesStandards%202025-02-10.pdf", "landing_page_url": "https://www.prescottvalley-az.gov/departments/public_works/index.php", "retrieved_at": "2026-08-14T15:27:09.408Z", "original_filename": "prescott-valley-az.pdf" } }, { "slug": "reno-nv", "processed_at": "2026-08-17T03:19:55.622Z", "detail_url": "https://stormwateratlas.com/reno-nv/", "data_url": "https://stormwateratlas.com/data/manuals/reno-nv.json", "document_metadata": { "jurisdiction_name": "Truckee Meadows (City of Reno, City of Sparks, and Washoe County)", "jurisdiction_level": "municipality", "state_code": "NV", "document_title": "Truckee Meadows Structural Controls Design and Low Impact Development Manual", "version_or_edition": "April 2015 Update", "adoption_or_effective_date": "2015-04-23", "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 25, 100 ], "water_quality_volume_method": "Volume-based BMPs sized using WQV = (P × RV × A) / 12, where P = 0.60 inches (90th percentile precipitation depth from Reno-Tahoe International Airport data) and RV = 0.05 + 0.009I (percent impervious). Flow-based BMPs sized using WQF = peak discharge from the 2-year storm via the Rational Method (Q = CIA).", "peak_flow_calculation_method": [ "Rational Method", "NRCS TR-55 Method", "HEC-1" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Vegetated Swales", "Vegetated Buffer Strips", "Infiltration Trenches", "Infiltration Basins", "Bioretention / Landscape Detention", "Sedimentation Basins", "Sand Filter Basins", "Stormwater Ponds", "Stormwater Wetlands", "Surface Sand Filters", "Underground Sand Filters", "Porous Pavements", "Hydrodynamic Separators", "Wet Vaults", "Catch Basin Inserts", "Modular Wetlands", "Media Filtration Systems", "Rainwater Catchment", "Green Roofs", "Source Controls" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "City of Reno, City of Sparks, and Washoe County, Nevada", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "City of Reno, City of Sparks, and Washoe County, Nevada", "page_or_section": "Cover" }, { "field": "document_metadata.state_code", "excerpt": "Reno, NV 89509", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Truckee Meadows Structural Controls Design and Low Impact Development Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "April 2015 Update", "page_or_section": "Cover" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Implementation of the source control and structural treatment control BMPs in this Manual will reduce pollutant loads in stormwater runoff ... to meet National Pollutant Discharge Elimination System (NPDES) permit requirements.", "page_or_section": "Section 1.1, Page 1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "structures designed to detain runoff volumes for the 5, 25 or 100-year storm", "page_or_section": "Section 3.3, Page 3-7" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQV = (P*RV*A)/12 ... P = 90th percentile precipitation depth (0.60 inches) ... When 'I' equals the rainfall intensity for the 2-year storm event, Q2 = WQF.", "page_or_section": "Section 6.3.1–6.3.2, Pages 6-3 to 6-5" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "For drainage areas greater than 100 acres, peak flow rates should be estimated using the NRCS TR-55 Method or HEC-1.", "page_or_section": "Section 6.3.1, Page 6-4" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "TC-10 Vegetated Swales ... TC-20 Infiltration Trenches ... TC-40 Sedimentation Basins ... TC-50 Stormwater Ponds ... TC-62 Porous Pavements ... MTC-10 Hydrodynamic Separators", "page_or_section": "Section 6.8–6.9 Table of Contents, Pages ii–iii" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 90th percentile precipitation depth (0.60 inches)", "page_or_section": "Section 6.3.2, page 6-4" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "To avoid mosquito breeding, t should not exceed 168 hours, or 7 days.", "page_or_section": "TC-21 Infiltration Basin, page 6-42" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The seasonal high water table should be more than 4 feet below the ground surface", "page_or_section": "TC-62 Porous Pavements siting, page 6-90" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "18\" min depth well mixed combination of Clean Sand (50-65%), Certified Compost or Peat Moss (5-20%), and Topsoil (20-30%)", "page_or_section": "Design Guidance Worksheet TC-30, page 315" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Maximum recommended ponding depth is 12 inches and minimum ponding depth is 6 inches", "page_or_section": "TC-30 Landscape Detention, page 6-48" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Minimum acceptable hydraulic conductivity is 0.5 in/hr (120 min/in) as tested with a minimum of three in-hole conductivity tests.", "page_or_section": "Infiltration Basin design criteria, page 6-42" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Target drain time, t. (48 hour min., 168 hour max.)", "page_or_section": "Design Guidance Worksheet TC-40, page 316" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Detention basin length to width ratio (minimum L:W = 2:1)", "page_or_section": "Design Guidance Worksheet TC-40, page 316" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Low flow channels should be designed with a minimum continuous grade of 0.5 percent.", "page_or_section": "Section 4.7 / vector control, page 4-24" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "WQV (0.60 in) and WQF (2-year Rational) sizing criteria are explicit. Regional manual covers Reno, Sparks, and Washoe County under MS4 permit NVS000001. Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "document_metadata.last_revised_date", "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.adoption_or_effective_date" ] }, "source": { "document_url": "https://www.reno.gov/Documents/Government/Departments/Public%20Works/Engineering%20Standards/Truckee%20Meadows%20Structural%20Controls%20Design%20and%20Low%20Impact%20Development%20Manual.pdf", "landing_page_url": "https://www.reno.gov/", "retrieved_at": "2026-08-08T01:30:00.000Z", "original_filename": "reno-nv.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": 168, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": 48, "length_to_width_ratio": 2, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T09:52:54.336Z", "enrich_model": "composer-2.5:run-fe4d731c-213e-495b-be84-05b1d0689c0d", "enrich_notes": "WQV sizing uses P=0.60 in and RV=0.05+0.009I (Section 6.3.2). Bioretention ponding DWQV is 6 in minimum and 12 in maximum (TC-30 worksheet and Section 6.8.3 narrative). Infiltration basin max drain time t must not exceed 168 h via t=WQV/(0.5(Kh/12)*A) with Kh minimum 0.5 in/hr. Porous pavement SHWT >4 ft; slopes up to 5% (blocks) or 15% (pavers) per type. ED sedimentation basins detain WQV minimum 48 h (up to 168 h max per TC-40).", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "denver-co", "processed_at": "2026-08-17T03:19:55.602Z", "detail_url": "https://stormwateratlas.com/denver-co/", "data_url": "https://stormwateratlas.com/data/manuals/denver-co.json", "document_metadata": { "jurisdiction_name": "Urban Drainage and Flood Control District (Denver Metro)", "jurisdiction_level": "special_district", "state_code": "CO", "document_title": "Urban Storm Drainage Criteria Manual Volume 3, Chapter 1: Stormwater Management and Planning", "version_or_edition": "November 2015", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2 ], "water_quality_volume_method": "Water Quality Capture Volume (WQCV) based on runoff from 0.6 inches of precipitation within the UDFCD boundary, representing runoff from frequent storm events such as the 80th percentile storm; remaining runoff after volume reduction is treated through capture and slow release of the WQCV.", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grass Buffers", "Grass Swales", "Bioretention (rain gardens)", "Permeable Pavement", "Green Roofs", "Extended Detention Basins", "Sand Filters", "Constructed Wetland Ponds", "Retention Ponds", "Underground BMPs", "Source Control BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "November 2015 Urban Drainage and Flood Control District", "page_or_section": "Page 1-1, Chapter 1" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Urban Drainage and Flood Control District", "page_or_section": "Page 1-1, Chapter 1" }, { "field": "document_metadata.state_code", "excerpt": "The Colorado Water Quality Control Act (25-8-101 et seq., CRS 1973, as amended)", "page_or_section": "Section 3.2, Page 1-7" }, { "field": "document_metadata.document_title", "excerpt": "Urban Storm Drainage Criteria Manual Volume 3 Chapter 1 Stormwater Management and Planning", "page_or_section": "Cover / Page 1-1" }, { "field": "document_metadata.version_or_edition", "excerpt": "November 2015 Urban Drainage and Flood Control District", "page_or_section": "Page 1-1, Chapter 1" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "UDFCD criteria are based on a Four Step Process focused on reducing runoff volumes, treating the remaining WQCV, stabilizing receiving drainageways and providing targeted source controls for post-construction operations at a site.", "page_or_section": "Section 6.0 Conclusion, Page 1-19" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "EURV represents the difference between the developed and pre-developed runoff volume for the range of storms that produce runoff from pervious land surfaces (generally greater than the 2-year event).", "page_or_section": "Common Stormwater Management Terms, Page 1-9" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Capture Volume (WQCV): This volume represents runoff from frequent storm events such as the 80th percentile storm. Within the UDFCD boundary, the WQCV is based on runoff from 0.6 inches of precipitation.", "page_or_section": "Common Stormwater Management Terms, Page 1-9; Section 4.2, Page 1-17" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "permeable pavement systems with subsurface storage, bioretention, extended detention basins, sand filters, constructed wetland ponds, and retention ponds. Green roofs and some underground BMPs may also provide the WQCV", "page_or_section": "Section 4.2, Page 1-17" }, { "field": "practice_mentions", "excerpt": "bioretention, extended detention basins, sand filters, constructed wetland ponds, and retention ponds.", "page_or_section": "p19" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Within the UDFCD boundary, the WQCV is based on runoff from 0.6 inches of precipitation.", "page_or_section": "Chapter 1, page 11, Common Stormwater Management Terms (WQCV definition)" }, { "field": "practice_mentions.bioretention", "excerpt": "Bioretention (rain gardens): The use of distributed on-site vegetated features such as rain gardens can help maintain natural drainage patterns", "page_or_section": "Chapter 1, Section 4.1, page 17" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Permeable Pavement: The use of various permeable pavement techniques as alternatives to paved areas can significantly reduce site imperviousness.", "page_or_section": "Chapter 1, Section 4.1, page 17" }, { "field": "practice_mentions.green_roof", "excerpt": "Green Roofs: Green roofs can be used to decrease imperviousness associated with buildings and structures.", "page_or_section": "Chapter 1, Section 4.1, page 17" }, { "field": "practice_mentions.swale", "excerpt": "Grass Swales: Like grass buffers, use of grass swales instead of storm sewers slows runoff and promotes infiltration", "page_or_section": "Chapter 1, Section 4.1, page 17" }, { "field": "practice_mentions.extended_detention", "excerpt": "including permeable pavement systems with subsurface storage, bioretention, extended detention basins, sand filters, constructed wetland ponds, and retention ponds.", "page_or_section": "Chapter 1, Section 4.2, page 19" }, { "field": "practice_mentions.sand_filter", "excerpt": "extended detention basins, sand filters, constructed wetland ponds, and retention ponds.", "page_or_section": "Chapter 1, Section 4.2, page 19" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "sand filters, constructed wetland ponds, and retention ponds.", "page_or_section": "Chapter 1, Section 4.2, page 19" }, { "field": "practice_mentions.wet_pond", "excerpt": "constructed wetland ponds, and retention ponds.", "page_or_section": "Chapter 1, Section 4.2, page 19" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Source is USDCM Volume 3 Chapter 1 only (planning and regulatory overview). WQCV (0.6 in.) and Four Step Process are explicit; peak flow calculation methods and required software appear in later chapters. Jurisdiction is UDFCD (Denver metro special district); document hosted at mhfd.org.", "fields_not_found": [ "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.mhfd.org/files/7af5d4c2f/03_Chapter-1-Stormwater-Management.pdf", "landing_page_url": "https://www.mhfd.org/criteria-manual-volume-3", "retrieved_at": "2026-08-08T00:55:00.000Z", "original_filename": "denver-co.pdf" }, "design_parameters": { "wqv_depth_inches": 0.6, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T08:06:26.338Z", "enrich_model": "composer-2.5:run-dd1b5ebd-a834-4a44-96c2-91ec4b5fd52c", "enrich_notes": "Chapter 1 is planning/regulatory only; WQCV tied to 0.6 in. precipitation within UDFCD. Detailed BMP sizing, drawdown, media depths, and infiltration rates are deferred to Chapters 2–5 and 3 (WQCV calculation).", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "ut-udot-drainage", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/ut-udot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/ut-udot-drainage.json", "document_metadata": { "jurisdiction_name": "Utah", "jurisdiction_level": "state", "state_code": "UT", "document_title": "UDOT Drainage Design Manual of Instruction", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)" ], "required_hydrologic_hydraulic_software": [ "HY-8" ], "approved_bmp_categories": [ "Infiltration Basin", "Infiltration Trench", "Detention Basin", "Retention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "UDOT Drainage Design Manual of Instruction", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "he Department’s drainage system for the 10 year storm event must not exceed 0.2 cu ft/sec/acre of developed area. Size the stor", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "........................... 4-2 4.2.3.3 Rational Method ........................................................................", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "storage volume. • Do not include infiltration or evapotranspiration losses when sizing the detention basin. 8.2.6 Hydraulic Analysis • Route inflow hydrographs with stage-storage and stage-discharge curves to determine detention basin volumes and discharge rates as follows", "page_or_section": "pp. 54–56" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Ensure that the 100 year, 24 hour storm event can be drained from the detention basin within 72 hours, excluding stormwater ponded at a micro pool.", "page_or_section": "Chapter 8, Section 8.2.3.1 Outlet Structure" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Provide at least 4 ft from the bottom of basins to the seasonal high groundwater elevation.", "page_or_section": "Chapter 8, Section 8.2.2.1 Grading" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Provide a minimum longitudinal slope of 0.5 percent.", "page_or_section": "Chapter 6, Section 6.2.4 Constructed Channels (roadside and median ditches; chapter 6.1 also lists swales)" }, { "field": "practice_mentions.infiltration_basin", "excerpt": "The Department will not allow any connection if the Department’s drainage system depends entirely on subsurface infiltration such as infiltration trenches, infiltration basins, dry wells, sumps or similar features.", "page_or_section": "Chapter 2, Section 2.8.2.3" }, { "field": "practice_mentions.infiltration_trench", "excerpt": "The Department will not allow any connection if the Department’s drainage system depends entirely on subsurface infiltration such as infiltration trenches, infiltration basins, dry wells, sumps or similar features.", "page_or_section": "Chapter 2, Section 2.8.2.3" }, { "field": "practice_mentions.swale", "excerpt": "Channels are natural or constructed conveyances for water and include rivers, streams, roadside and median ditches, swales and irrigation flows.", "page_or_section": "Chapter 6, Section 6.1 INTRODUCTION" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. UDOT Drainage Design Manual of Instruction (Google Drive export) Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://drive.google.com/uc?export=download&id=1sxmhKziSdENiN03kQUhUlu8xyAHMdJol", "landing_page_url": "https://connect.udot.utah.gov/docs/drainage-design-manual-of-instruction/", "retrieved_at": "2026-08-11T17:59:10.541Z", "original_filename": "ut-udot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 72, "shwt_separation_inches": 48, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 0.5, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "infiltration_basin", "infiltration_trench", "swale" ], "enriched_at": "2026-08-13T10:27:12.653Z", "enrich_model": "composer-2.5:run-72168d8a-95d7-4bc1-9036-abbe4cc0442d", "enrich_notes": "Stormwater quality sizing and BMP criteria are delegated to the UDOT Stormwater Quality Design Manual (Ch. 5, 6, 8). Offsite connections are prohibited when UDOT’s system relies entirely on subsurface infiltration (infiltration trenches, infiltration basins, dry wells). Detention basin chapter addresses flood-control detention with optional WQ features (forebays, micro pools).", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "vt-state", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/vt-state/", "data_url": "https://stormwateratlas.com/data/manuals/vt-state.json", "document_metadata": { "jurisdiction_name": "Vermont", "jurisdiction_level": "state", "state_code": "VT", "document_title": "The Vermont Stormwater Management Manual Volume I – Stormwater Treatment Standards", "version_or_edition": "DRAFT March 1, 2016", "adoption_or_effective_date": null, "last_revised_date": "2016-03-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 10, 100 ], "water_quality_volume_method": "WQv = (P)(Rv)(A) / 12, where P = 1.0 inch, Rv = 0.05 + 0.009(I), I = percent impervious, A = site area in acres.", "peak_flow_calculation_method": [ "NRCS Runoff methods", "Watershed Lag Method", "TR-55", "TR-20" ], "required_hydrologic_hydraulic_software": [ "TR-55", "TR-20", "HECRAS" ], "approved_bmp_categories": [ "Pre-Treatment Practices", "Non-Structural Practices", "Structural Stormwater Treatment Practices", "Alternative Stormwater Treatment Practices" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "The Vermont Stormwater Management Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Vermont Agency of Natural Resources", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Natural Resource Conservation Service (NRCS) methods for calculating runoff have been found to underestimate the volume and rate of runoff for rainfall events less than 2\". In order to adapt NRCS methods for the water quality storm, a modified Curve Number (CN) shall be", "page_or_section": "p. 17" }, { "field": "document_metadata.document_title", "excerpt": "The Vermont Stormwater Management Manual Volume I – Stormwater Treatment Standards", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "DRAFT March 1, 2016", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "DRAFT March 1, 2016", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This manual was produced to provide technical analysis and design guidance for the Vermont Agency of Natural Resources Stormwater Management Program.", "page_or_section": "1-1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "1-year 24 hour storm... 10-year storm... 100-year storm", "page_or_section": "2-2" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "WQTS in acre- feet of storage: WQv = (P)(Rv)(A) 12 where: WQv = water quality treatment volume (acre-feet) P = 1.0 inch across Vermont Rv = volumetric runoff coefficient, equal to: [0.05 + 0.009(I)] I = whole number percent impervious of the site A = site area (in acres) In as", "page_or_section": "p. 16" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "The Watershed Lag Method shall be used for determination of peak rates", "page_or_section": "2-13" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The models TR-55 and TR-20 (or approved equivalent) will be used for determining peak discharge rates", "page_or_section": "2-14" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Pre-Treatment Practices, Non-Structural Practices, Structural Stormwater Treatment Practices", "page_or_section": "Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "P = 1.0 inch across Vermont", "page_or_section": "Section 2.2.4 WQTS, page 16" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "equivalent to the first inch of rainfall", "page_or_section": "Section 2.2.4, page 16" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Maximum dewatering time for Tv of 48 hours", "page_or_section": "Section 4.3.3.1 Design Summary, page 124" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Dry Swale Dewatering Maximum dewatering time of 48 hours", "page_or_section": "Section 4.3.2.1, page 111" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Vertical separation by at least three feet from the seasonally high groundwater table (SHGWT)", "page_or_section": "Section 4.3.3.1, page 124" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "minimum 3 foot separation to SHGWT from the bottom of the practice", "page_or_section": "Section 4.3.1.2 Bioretention Feasibility, page 101" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Filter Bed Depth 24-48 inches", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Max. Ponding Depth 12 inches", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Infiltration rate of 0.2 in/hr or greater if exfiltrating", "page_or_section": "Bioretention Design Summary, page 97" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "infiltration rate (fc) of at least 0.2 inches per hour", "page_or_section": "Section 4.3.1.2, page 101" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "deep water zones with a depth equal to or greater than four feet", "page_or_section": "Section 4.3.6.5 Wet Pond Treatment, page 167" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "ED storage volume shall not exceed 50% of the WQv and shall drain over 24 hours", "page_or_section": "Section 4.3.5 Design Summary, page 147" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "12 hours of extended detention is required ... 24 hours of extended detention is required", "page_or_section": "Section 2.2.5.2 Extended Detention Method, page 19" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Geometry (length to width ratio) 3:1 or more", "page_or_section": "Section 4.3.6.1 Wet Pond Design Summary, page 159" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "The minimum length to width ratio for a shallow treatment wetland is 2:1", "page_or_section": "Section 4.3.5.1, page 150" }, { "field": "design_parameters.swale_bottom_width_inches", "excerpt": "Swales shall have a bottom width between two and eight feet", "page_or_section": "Section 4.3.2.5, page 117" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Open channels constructed without check dams shall have a maximum longitudinal slope of 2%", "page_or_section": "Section 4.3.2.2, page 114" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "http://legislature.vermont.gov/Documents/2016/WorkGroups/House%20Fish%20and%20Wildlife/Stormwater%20Manual%20Revisions/W~Kevin%20Burke~Draft%20Stormwater%20Manual%20Revisions%20DEC~3-22-2016.pdf", "landing_page_url": "https://dec.vermont.gov/watershed/stormwater", "retrieved_at": "2026-08-07T11:29:27.033Z", "original_filename": "vt-state.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 36, "bioretention_media_depth_min_inches": 24, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.2, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 24, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": 24, "swale_longitudinal_slope_percent": 2, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:30:00.163Z", "enrich_model": "composer-2.5:run-04344fd1-11a2-45d2-9bba-38e073f0f471", "enrich_notes": "WQv uses P=1.0 inch (90th percentile / first inch). Minimum 0.2 watershed inches WQV for low-impervious pervious areas. SHGWT separation is tiered for bioretention/dry swale/filtering when infiltrating >WQv: 36 in (3 ft) default, 24 in if CDA ≤1 ac and >50% impervious, 12 in if CDA ≤1 ac and ≤50% impervious. Infiltration trenches/basins require 36 in to SHGWT/bedrock (12 in for qualifying dry wells). Channel protection extended detention: 12 h cold-water fisheries, 24 h warm-water. Shallow surface treatment wetland minimum flowpath 2:1; gravel wetland 1:1; wet pond 3:1. Bioretention filter drain time recommended max 48 h.", "enrich_schema_version": 2, "fields_not_found": [ "permeable_pavement_storage_depth_inches", "wetland_detention_hours", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "va-state", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/va-state/", "data_url": "https://stormwateratlas.com/data/manuals/va-state.json", "document_metadata": { "jurisdiction_name": "Virginia Department of Environmental Quality (DEQ)", "jurisdiction_level": "state", "state_code": "VA", "document_title": "Virginia Stormwater Management Handbook, Chapter 8 — BMP Overview and Selection Criteria", "version_or_edition": "July 2013", "adoption_or_effective_date": "2013-07", "last_revised_date": "2013-07", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 100 ], "water_quality_volume_method": "Treatment Volume (Tv) from impervious surfaces sized to at least the first 1 inch of rainfall for runoff volume reduction BMPs. Practices are designed to capture and treat the full Tv (filtering, swales/open channels, infiltration, and basins with permanent pools).", "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Runoff volume reduction (vegetated roof, downspout disconnection, rainwater harvesting, soil compost amendments, sheet flow to vegetated filters or conserved open space)", "Swales or open channels (grass channel, dry swale)", "Filtering systems (filtering practices / sand filters, bioretention)", "Infiltration practices (permeable pavement, infiltration practices, bioinfiltration)", "Basins — ponds and wetlands (constructed wetlands, wet ponds, extended detention)", "Manufactured Treatment Devices (MTDs) verified via Virginia Stormwater BMP Clearinghouse / DEQ", "Treatment trains" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "both administered in Virginia through delegation to the DEQ", "page_or_section": "Section 8.0 Introduction, Page 8-4" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Virginia Stormwater Management Handbook, Chapter 8 July 2013", "page_or_section": "Header throughout" }, { "field": "document_metadata.state_code", "excerpt": "Virginia Stormwater Management Handbook", "page_or_section": "Header" }, { "field": "document_metadata.document_title", "excerpt": "Chapter 8 BMP OVERVIEW AND SELECTION CRITERIA", "page_or_section": "Page 8-1" }, { "field": "document_metadata.version_or_edition", "excerpt": "Virginia Stormwater Management Handbook, Chapter 8 July 2013", "page_or_section": "Header" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Virginia Stormwater Management Handbook, Chapter 8... Complete standards and specifications for Virginia-approved post-construction BMPs and MTDs can be found on the Virginia BMP Clearinghouse web site", "page_or_section": "Header; Section 8.3, Page 8-41" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "In Virginia, control of the 1-year 24-hour storm volume is considered the standard necessary to protect stream channel geomorphology", "page_or_section": "Section 8.1.9, Page 8-11" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "protect, preserve, or otherwise manage the ultimate 100-year floodplain", "page_or_section": "Section on aquatic buffers / floodplains" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Generally, runoff volume reduction BMPs are designed to handle at least the Treatment Volume from impervious surfaces (first 1-inch of rainfall).", "page_or_section": "Section 8.1.9, Page 8-11" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "The following practices are explicitly designed to capture and treat the full Treatment Volume (Tv) within dry or wet cells... The following practices capture and temporarily store the Treatment Volume (Tv) before passing it through a filter bed", "page_or_section": "Sections 8.2.2.2–8.2.2.3, Pages 8-34–8-35" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "8.2.2. Approved Virginia Non-Proprietary Stormwater Control Measures... Runoff volume reduction... Swales or open channels... Filtering systems... Infiltration practices... Basins", "page_or_section": "Section 8.2.2, Page 8-32" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Virginia allows the use of certain Manufactured Treatment Devices (MTDs) for which pollution removal performance has been verified and certified through by the Virginia Stormwater BMP Clearinghouse Committee and the DEQ.", "page_or_section": "Section 8.2.2.6, Page 8-40" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "combined in a \"treatment train\" with one or more other BMPs to meet water quality requirements", "page_or_section": "Section 8.2.2.7, Page 8-40" }, { "field": "design_infiltration_rate_in_per_hr", "excerpt": "Infiltration practices are suitable for use in residential and other urban areas where measured soil permeability rates exceed 0.5 inch per hour.", "page_or_section": "8.2.2.4 Infiltration Practices, 8-37" }, { "field": "permanent_pool_depth_inches", "excerpt": "max. normal pool depth of 4 feet", "page_or_section": "Table 8.6 BMP Selection Matrix 4, 8-49" }, { "field": "ed_drain_time_hours", "excerpt": "Provide long ED (> 48 hrs) for max. bacteria die-off", "page_or_section": "Table 8.6 BMP Selection Matrix 4, 8-49" }, { "field": "wetland_detention_hours", "excerpt": "Generally the goal is to hold the flows for at least 24 hours to maximize the opportunity of settling, adsorption, and transformation of pollutants", "page_or_section": "8.1.11 Peak Flow Reduction and Runoff Treatment, 8-19" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Chapter 8 only (July 2013 clearinghouse PDF) — BMP overview/selection, not the full Virginia Stormwater Management Handbook (EncodePlus). Treatment Volume (first 1-inch) and 1-year/24-hour channel protection are stated here; detailed hydrologic/peak-flow calculation methods and required software live in other handbook chapters and are not in this excerpt. 100-year appears mainly for floodplain setbacks and optional enlarged volume-reduction BMPs, not as a complete flood-control design chapter. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.design_storm_return_periods_years (complete VSMP quantity/flood return periods beyond 1-year channel protection and 100-year floodplain references in this chapter)", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://swbmpvwrrc.wp.prod.es.cloud.vt.edu/wp-content/uploads/2018/07/31_Chap-8_BMP-Overview-Selection.pdf", "landing_page_url": "https://www.deq.virginia.gov/water/stormwater/stormwater-construction/handbooks", "retrieved_at": "2026-08-08T10:25:00.000Z", "original_filename": "va-state.txt" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": 24, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "green_roof", "infiltration_basin", "infiltration_trench", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:27:54.346Z", "enrich_model": "composer-2.5:run-2c6afaa8-df77-44b5-97f8-642ac2db9b49", "enrich_notes": "Chapter 8 is BMP overview and selection (July 2013); section 8.3 points to separate design standards. Treatment Volume sizing and detailed hydrology are not specified numerically in this excerpt except where noted in selection matrices. Infiltration suitability cites soil permeability above 0.5 in/hr; wet ponds cite max normal pool 4 ft and extended detention longer than 48 hr for bacteria die-off; pond-type BMPs cite holding flows at least 24 hr.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "length_to_width_ratio", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "va-vdot-drainage", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/va-vdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/va-vdot-drainage.json", "document_metadata": { "jurisdiction_name": "Virginia Department of Transportation (VDOT)", "jurisdiction_level": "state", "state_code": "VA", "document_title": "VDOT Drainage Manual — Chapter 11 Stormwater Management", "version_or_edition": "July 2026", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 100 ], "water_quality_volume_method": "Water Quality Volume Computation and BMP Selection Procedure", "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "Modified Rational Method" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Bioretention", "Wet Pond", "Extended Detention", "Filter Strip", "Permeable Pavement", "Constructed Wetland", "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Virginia Department of Transportation (VDOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "VDOT Drainage Manual — Chapter 11 Stormwater Management", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "lated sediment removed about every 5 to 10 years or as necessary based upon a SWMF inspection. Chapter 11-11 of 158 11.4 Part V", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "............. 11-80 11.5.7.1.1 Modified Rational Method, Simplified Triangular Hydrograph ................. 11-80 Routing ......", "page_or_section": null }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "Water Quality Volume Computation and BMP Selection Procedure", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Bioretention, Wet Pond, Extended Detention, Filter Strip", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "the product of the \"Target Rainfall Event\" (1.00 inch), the site area (acres), and the site Rv from the VRRM", "page_or_section": "Chapter 11, 11.5.6 / page 80 (c0116)" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "The first flush, or water quality volume (WQV) is generally defined as the first one-half inch of runoff from impervious surfaces.", "page_or_section": "Chapter 11, 11.7.1 Water Quality / page 119 (c0138)" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "3:1 length-to-width ratio*; wedge shaped (wider at the outlet); permanent pool depth to 3' max, if possible", "page_or_section": "Table 11-7 Summary of Design Criteria for Dry and Wet Basins / pages 116-117 (c0137)" }, { "field": "design_parameters.length_to_width_ratio", "excerpt": "Shape 3:1 length-to-width ratio; wedge shaped (wider at the outlet)", "page_or_section": "Table 11-7 Summary of Design Criteria for Dry and Wet Basins / page 116 (c0137)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention Level 1 specifies 24-hours or less draw down for the average Tv time, while the Extended Detention Level 2 design requires an average Tv draw down time of 36 hours.", "page_or_section": "Chapter 11, 11.5.6 / page 80 (c0116)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention Basins and Enhanced Extended Detention Basins require a 30 hour drawdown time for the required WQV.", "page_or_section": "Chapter 11, 11.6.2 / page 110 (c0132)" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "The brim drawdown requirement for water quality for extended detention design is 30 hours.", "page_or_section": "Chapter 11, 11.7.4 Detention Time / page 121 (c0139)" }, { "field": "practice_mentions.extended_detention", "excerpt": "SWM wet ponds and extended detention ponds that are not covered by the Impounding Structure Regulations", "page_or_section": "11.3.5 Impounding Facilities / page 9 (c0030)" }, { "field": "practice_mentions.manufactured_treatment", "excerpt": "Manufactured Treatment Devices (MTDs) or proprietary BMPs accepted by DEQ may be utilized, when accepted by VDOT", "page_or_section": "Chapter 11 / page 16 (c0049)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. VDOT Drainage Manual Chapter 11 Stormwater Management (July 2026). Full combined PDF ~161MB deferred.", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.vdot.virginia.gov/media/vdotvirginiagov/doing-business/technical-guidance-and-support/technical-guidance-documents/location-and-design/migrated/drainagemanual/Drain-Manual-Chapter-11_acc07072026.pdf", "landing_page_url": "https://www.vdot.virginia.gov/doing-business/technical-guidance-and-support/technical-guidance-documents/drainage-manual/", "retrieved_at": "2026-08-11T17:21:06.018Z", "original_filename": "va-vdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 36, "ed_drain_time_hours": null, "length_to_width_ratio": 3, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:28:47.071Z", "enrich_model": "composer-2.5:run-deaac8ee-f46e-4960-986b-e2e9531d1fe4", "enrich_notes": "Chapter 11 references VRRM (Target Rainfall Event 1.00 inch for Tv) and older Part V Article 4 text defining WQV as the first 0.5 inch of runoff from impervious surfaces (Table 11-1 framework). Extended-detention drawdown times vary by standard: ED Level 1 ≤24 hr average Tv; ED Level 2 36 hr; Extended/Enhanced ED basins 30 hr WQV brim drawdown. Example problems assume depth to seasonal high groundwater and bedrock >6 ft (site suitability), not a minimum SHWT separation for SCM design. Detailed bioretention, permeable pavement, swale geometry, and infiltration rate criteria are deferred to VDOT BMP Design Manual of Practice, Virginia Stormwater BMP Clearinghouse, and VSWMH v1.2. MTDs require DEQ acceptance and VDOT approval via product lists; no TAPE/NJCAT-style program name in excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "ed_drain_time_hours", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wa-state-western", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wa-state-western/", "data_url": "https://stormwateratlas.com/data/manuals/wa-state-western.json", "document_metadata": { "jurisdiction_name": "Washington", "jurisdiction_level": "state", "state_code": "WA", "document_title": "Stormwater Management Manual for Western Washington", "version_or_edition": "2024 Edition", "adoption_or_effective_date": "2024-07", "last_revised_date": "2024-07", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 10, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Continuous Simulation Models", "Single Event Hydrograph Method", "Rational method", "SBUH", "SCS method", "NRCS Method", "HSPF" ], "required_hydrologic_hydraulic_software": [ "WWHM", "HSPF" ], "approved_bmp_categories": [ "Flow Control BMPs", "Runoff Treatment BMPs", "LID BMPs", "Source Control BMPs", "Construction Stormwater BMPs", "Pretreatment BMPs", "Oil Control BMPs", "Phosphorus Treatment BMPs", "Metals Treatment BMPs", "Basic Treatment BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Washington State Department of Ecology", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Washington State Department of Ecology\nWater Quality Program", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "Issaquah, WA", "page_or_section": "Appendix I-B: Altering the MRs with Basin Plans, Page 199" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management Manual for Western Washington", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "2024 Stormwater Management Manual for Western Washington", "page_or_section": "page 5" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Prepared by: Washington State Department of Ecology", "page_or_section": "Title Page" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "2-year, 10-year or 100-year storm", "page_or_section": "Glossary, Page 1312 (Storm frequency)" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Rational method", "page_or_section": "Glossary, page 1303" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "Precipitation Stations Used in WWHM Creation", "page_or_section": "Table of Contents, page 30" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "The types of BMPs that this manual refers to are: Flow Control BMPs, Runoff Treatment BMPs, LID BMPs, Source Control BMPs, Construction BMPs.", "page_or_section": "Volume I - Chapter 1 - Page 71" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Document that the maximum ponded depth from the infiltration BMP can infiltrate through the infiltration BMP surface within 48 hours.", "page_or_section": "Volume V - Chapter 5 - Page 823 (SSC-4 Soil Infiltration Rate/Drawdown Time)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "In most cases, UIC wells are designed to completely drain ponded runoff within 48 to 72 hours after flow to the UIC well has stopped.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "The base of BMP T7.10: Infiltration Ponds or BMP T7.20: Infiltration Trenches shall be ≥ 5 feet above the seasonal high-water mark, bedrock (or hardpan) or other low permeability layer. A separation down to 3 feet may be considered", "page_or_section": "Volume V - Chapter 5 - Page 823 (SSC-5)" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A 5-foot separation between the bottom of the well and the top of the groundwater is required, unless a demonstrative approach confirms that a separation of 3 feet will meet the nonendangerment standard.", "page_or_section": "Volume I - Chapter 4 - Page 166" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "The \"Default\" and \"Custom\" BSM depth must be 18 inches to provide Runoff Treatment and good growing conditions for selected plants.", "page_or_section": "Volume V - Chapter 5 - Page 921" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "If the high water table extends to within five (5) feet of the bottom of an infiltration BMP, the site is seldom suitable.", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "They are not generally appropriate for sites that have a design infiltration rate less than 0.3 inches per hour.", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Design (long-term) infiltration rates up to 3 in/hr can also be considered", "page_or_section": "Volume V - Chapter 5 - Page 822 (SSC-4)" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Use an initial saturated hydraulic conductivity (Ksat)for the Bioretention Soil Mix (BSM) of 12 in/hr.", "page_or_section": "Volume V - Chapter 5 - Page 910" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Deep ponds (greater than 8 feet) may stratify during summer", "page_or_section": "Volume III - Chapter 1 - Page 478" }, { "field": "design_parameters.permeable_pavement_storage_depth_inches", "excerpt": "The permeable pavement design includes a 6\" layer of sand that meets the size gradation (by weight) given in Table V-7.1: Sand Medium Specification.", "page_or_section": "Volume V - Chapter 5 - Page 838" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "biofiltration swales are usually situated on sites with slopes of less than 6%, although greater slopes can be considered.", "page_or_section": "Volume III - Chapter 1 - Page 478" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "All requested fields populated accurately from standard available state manual context. Water quality volume calculation details were omitted from the provided text, leaving the water quality volume method null. Pipeline excerpt repair removed 2 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date" ] }, "source": { "document_url": "https://www.cityofcamas.us/sites/default/files/fileattachments/community_development/page/9505/2024swmmww_6-14-24.pdf", "landing_page_url": "https://www.ecology.wa.gov/regulations-permits/guidance-technical-assistance/stormwater-permittee-guidance-resources/stormwater-manuals", "retrieved_at": "2026-08-07T11:33:14.322Z", "original_filename": "wa-state-western.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": 48, "shwt_separation_inches": 60, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:30:23.281Z", "enrich_model": "composer-2.5:run-15fcaecd-6c82-4db6-b1d9-efa1f41386a1", "enrich_notes": "Manual cites multiple SHWT separations by practice: 5 ft (60 in) default for infiltration ponds/trenches and UIC presumptive rule; 3 ft (36 in) may be allowed with analysis; permeable pavement and small rain gardens use 1 ft (12 in) to restriction layer; bioretention uses 1 ft or 3 ft by contributing area thresholds. UIC drawdown stated as 48–72 hours. Site infeasibility for infiltration when native design rate < 0.3 in/hr; long-term design rates up to 3 in/hr and BSM design Ksat 12 in/hr are referenced but no single mandated design infiltration rate. Wet pond permanent pool: deep ponds > 8 ft may stratify (maximum guidance, not minimum pool depth). Permeable pavement treatment sand layers 6 in (basic) and 12 in (basic + metals) are treatment layers, not a named storage depth.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wa-wsdot-hr", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wa-wsdot-hr/", "data_url": "https://stormwateratlas.com/data/manuals/wa-wsdot-hr.json", "document_metadata": { "jurisdiction_name": "Washington State Department of Transportation (WSDOT)", "jurisdiction_level": "state", "state_code": "WA", "document_title": "Highway Runoff Manual M 31-16 — Chapter 3 Minimum Requirements", "version_or_edition": "April 2014 (M 31-16.04)", "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 25, 50, 100 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Washington State Department of Transportation (WSDOT)", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "Highway Runoff Manual M 31-16 — Chapter 3 Minimum Requirements", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "auses a 0.1 cfs or more increase in the 100-year recurrence interval flow? Chapter 3 Minimum Requirements WSDOT Highway Runoff M", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "No water-quality rainfall/runoff depth in inches (e.g. 1.0 in.) stated; western volume-based wetpool uses \"91st percentile, 24-hour runoff volume as calculated by MGSFlood.\"", "page_or_section": "Table 3-3, page 3-17" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Do not place flow control BMPs or the live storage portion of a combination flow control/runoff treatment BMP below the seasonal high water table.", "page_or_section": "Section 3-3.6.4 Guidelines, page 3-24" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Size treatment facility or facilities using the full 2-year release rate from the detention facility, under postdeveloped conditions for each TDA.", "page_or_section": "Table 3-3, page 3-17" }, { "field": "practice_mentions.wet_pond", "excerpt": "Volume-based (on-line) Wetpool – Size the wetpool to store the 91st percentile, 24-hour runoff volume as calculated by MGSFlood.", "page_or_section": "Table 3-3, page 3-17" }, { "field": "practice_mentions.constructed_wetland", "excerpt": "Refer to Section 5-4.1.4 for additional information on the Constructed Stormwater Treatment Wetland (see BMP RT.13).", "page_or_section": "Section 3-3.7, page 3-29" }, { "field": "practice_mentions.permeable_pavement", "excerpt": "Model pervious pavement as grass in this analysis.", "page_or_section": "Section 3-3.6.4 Guidelines, page 3-24" }, { "field": "practice_mentions.extended_detention", "excerpt": "Flow-based: downstream of flow control facility — Size treatment facility or facilities using the full 2-year release rate from the detention facility.", "page_or_section": "Table 3-3, page 3-17" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. WSDOT Highway Runoff Manual Ch3 Minimum Requirements (2014). Full HRM PDF ~240MB deferred.", "fields_not_found": [ "design_criteria.peak_flow_calculation_method", "design_criteria.water_quality_volume_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://www.wsdot.wa.gov/publications/fulltext/hydraulics/hrm/chap3_2014.pdf", "landing_page_url": "https://wsdot.wa.gov/engineering-standards/all-manuals-and-standards/manuals/highway-runoff-manual", "retrieved_at": "2026-08-11T17:21:06.028Z", "original_filename": "wa-wsdot-hr.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "constructed_wetland", "extended_detention", "infiltration_basin", "permeable_pavement", "wet_pond" ], "enriched_at": "2026-08-13T10:30:51.120Z", "enrich_model": "composer-2.5:run-77ecf14c-73d7-4177-bc06-a66ce449fb99", "enrich_notes": "Chapter 3 defines minimum requirements and sizing frameworks (Tables 3-3 western WA: 91% annual average runoff for flow-based treatment; wetpool sized to 91st percentile 24-hour runoff via MGSFlood; downstream-of-detention uses full 2-year release rate. Table 3-4 eastern WA: 6-month long-duration volume and 6-month short-duration peak for flow-based sizing). Explicit inch-depth WQV, drawdown hours, SHWT separation distance, and BMP detail dimensions are not in this chapter proxy text—refer to Chapters 4–5. Flow control guidance prohibits live storage below seasonal high water table without stating a minimum separation in inches.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wayne-county-mi", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wayne-county-mi/", "data_url": "https://stormwateratlas.com/data/manuals/wayne-county-mi.json", "document_metadata": { "jurisdiction_name": "Wayne County", "jurisdiction_level": "county", "state_code": "MI", "document_title": "Wayne County Stormwater Control Program — Standards Manual", "version_or_edition": "Effective September 3, 2021", "adoption_or_effective_date": "2021-09-03", "last_revised_date": "2021-09-03", "relationship_to_state_manual": "independent" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 100 ], "water_quality_volume_method": "First Flush / WQC: remove ≥80% TSS or limit peak TSS to 80 mg/L for the first 1.0 inch of rainfall. CPVC: infiltrate first 1.0 inch of rainfall where soils/groundwater permit. CPRC: store and release volume from a 1.9-inch storm over ≥48 hours.", "peak_flow_calculation_method": [ "100-year flood control: ≤0.15 cfs/acre for drainage areas ≥100 acres", "Variable release rate curve for areas <100 acres (0.15–1.0 cfs/acre)", "Detention / retention systems with flow restrictors" ], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Open detention basins", "Retention basins", "Underground detention", "Bioretention", "Water quality / infiltration systems", "Pretreatment systems", "Conveyance BMPs" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Wayne County Stormwater Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "Wayne County", "page_or_section": "Cover" }, { "field": "document_metadata.document_title", "excerpt": "Wayne County Stormwater Standards Manual", "page_or_section": "Cover" }, { "field": "document_metadata.version_or_edition", "excerpt": "September 2021", "page_or_section": "Footer" }, { "field": "document_metadata.adoption_or_effective_date", "excerpt": "effective September 3, 2021", "page_or_section": "Landing / cover program" }, { "field": "document_metadata.last_revised_date", "excerpt": "September 2021", "page_or_section": "Footer" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Wayne County Stormwater Ordinance, Administrative Rules, and Standards Manual", "page_or_section": "Introduction" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "100-year recurrence interval storm; 2-year recurrence interval storm", "page_or_section": "Chapter 5" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "remove 80 percent or more of the total suspended solids (TSS) load ... first one (1) inch of rainfall", "page_or_section": "§5.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "peak flow rate ... must not exceed 0.15 cfs/acre for a 100-year recurrence interval storm", "page_or_section": "§5.1" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basins; Underground Detention; Bioretention; Water Quality/Infiltration Systems", "page_or_section": "Chapter 8 TOC" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Provide water quality control for the first one (1) inch of rainfall.", "page_or_section": "6.3.1 First Flush Treatment, page 43" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "Prevailing groundwater exists within two (2) vertical feet of the bottom of the infiltration BMP", "page_or_section": "6.3.1 First Flush Treatment / CPVC waiver, page 43-45" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Each bioretention cell is designed with the maximum 12-inch ponding depth", "page_or_section": "Chapter 11 Sample Calculations, page 127" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "The permanent pool in a traditional detention basin must be a minimum of 4 feet deep.", "page_or_section": "6.2.1 Detention Systems, page 38" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Store and release the volume generated by a 1.9-inch storm event for a discharge duration of 48 hours", "page_or_section": "6.3.1 / CPRC, page 43" }, { "field": "design_parameters.ed_drain_time_hours", "excerpt": "Extended Detention means the storage and gradual release of stormwater from a detention system over a period of not less than 48 hours.", "page_or_section": "Administrative Rules definitions, page 227" } ], "extraction_quality": { "confidence": "high", "needs_human_review": true, "review_notes": "Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.required_hydrologic_hydraulic_software", "document_metadata.state_code" ] }, "source": { "document_url": "https://www.waynecountymi.gov/files/assets/mainsite/v/1/environmental-services/documents/land-resource-management/wqm-wcsw-mgmt-plan-9-3-2021.pdf", "landing_page_url": "https://www.waynecountymi.gov/Government/Departments/Environmental-Services/Water-Quality-Management/Storm-Water-Management/Standards-Manual", "retrieved_at": "2026-08-10T09:24:56.027Z", "original_filename": "wayne-county-mi.pdf" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": null, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": 12, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": 48, "ed_drain_time_hours": 48, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "infiltration_basin", "manufactured_treatment", "permeable_pavement", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:31:39.032Z", "enrich_model": "composer-2.5:run-1d87a801-dc13-483f-b8df-f1d7588bf017", "enrich_notes": "CPVC tied to 1-inch rainfall volume (VCPVC = A * C * 3630 ft³); active infiltration credited over six hours for bioretention. CPRC uses 1.9-inch storm released over ≥48 hours. In-situ infiltration thresholds: BMPs not permitted below 0.10 in/hr; CPVC waiver when below 0.24 in/hr or GW within 2 ft of BMP bottom. Forebay first-flush release over 24 hours. Traditional detention permanent pool minimum 4 ft; constructed wetland pool 0.5–3.0 ft by vegetation. Retention basin max storage depth 6 ft. Permeable pavement design deferred to DWSD manual.", "enrich_schema_version": 2, "fields_not_found": [ "max_drawdown_hours", "bioretention_media_depth_min_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "west-virginia-manual", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/west-virginia-manual/", "data_url": "https://stormwateratlas.com/data/manuals/west-virginia-manual.json", "document_metadata": { "jurisdiction_name": "West Virginia", "jurisdiction_level": "state", "state_code": "WV", "document_title": "West Virginia Stormwater Management and Design Guidance Manual", "version_or_edition": "November 2012", "adoption_or_effective_date": null, "last_revised_date": "2012-11-01", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10 ], "water_quality_volume_method": "Runoff Reduction Method: manage on-site runoff from a one-inch rainfall event (90th percentile; Treatment Volume Tv). Tv uses volumetric runoff coefficients (Rv) for impervious cover, managed turf/disturbed soils, and forest/open space land covers.", "peak_flow_calculation_method": [ "Runoff Reduction Method with adjusted NRCS curve numbers (TR-55 Equations 2-1 through 2-4)", "Rational Method", "NRCS TR-55 single-event design storm methodology", "Continuous simulation rainfall-runoff modeling" ], "required_hydrologic_hydraulic_software": [ "Design Compliance Spreadsheet", "TR-55" ], "approved_bmp_categories": [ "Better Site Design Practices", "Sheet Flow to Vegetated Filter Strips and Conservation Areas", "Impervious Surface Disconnection", "Bioretention", "Permeable Pavement", "Grass Swale", "Infiltration", "Regenerative Stormwater Conveyance System", "Rainwater Harvesting", "Vegetated Roofs", "Filtration Practice", "Stormwater Wetlands" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "West Virginia Stormwater Management and Design Guidance Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "West Virginia Department of Environmental Protection", "page_or_section": "Title Page" }, { "field": "document_metadata.state_code", "excerpt": "West Virginia Stormwater Management", "page_or_section": "Title Page" }, { "field": "document_metadata.document_title", "excerpt": "Stormwater Management and Design Guidance Manual", "page_or_section": "Title Page" }, { "field": "document_metadata.version_or_edition", "excerpt": "November 2012", "page_or_section": "Title Page" }, { "field": "document_metadata.last_revised_date", "excerpt": "November 2012", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "manual will be used to implement stormwater management practices that will help to protect and restore water bodies", "page_or_section": "Foreword" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "keep and manage on site the first one inch of rainfall from a 24-hour storm", "page_or_section": "2.5" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "locally-required 2-year or 10-year or larger frequency storm event detention or peak flow standards", "page_or_section": "3.4.4" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "90% of the annual rainfall events are one (1) inch or less. Therefore, the BMP Performance Goal is to manage on-site the runoff from a one-inch rainfall event", "page_or_section": "3.2.2" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "utilizes the NRCS TR55 runoff equations 2-1 through 2-4 to derive a reduced curve number", "page_or_section": "3.4.4" }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "Another common modeling tool is the Rational Method", "page_or_section": "3.4.1" }, { "field": "design_criteria.required_hydrologic_hydraulic_software", "excerpt": "The Design Compliance Spreadsheet is a tool that integrates the runoff volume reduction methods", "page_or_section": "3.4.5" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "4.2.3. Bioretention (BR) ... 4.2.4. Permeable Pavement (PP) ... 4.2.11. Stormwater Wetlands (SW)", "page_or_section": "Table of Contents" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "manage on-site runoff from a one-inch rainfall event", "page_or_section": "Atlas context / reducing one inch of rainfall" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "100% of that needed to meet the one inch performance standard", "page_or_section": "Table BR-1 footnote 2, BR.5" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Water infiltrates into the underlying soil within 48 hours.", "page_or_section": "Table 3.1 / Table BR-1 Level 2" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "The underdrain should be sized so that the Bioretention practice fully drains within 48 hours.", "page_or_section": "BR-4.10, BR.25" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "td = design drain time of sump = 48 hours", "page_or_section": "Design Example 6.2, Equation PP-2, page 424" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "A separation distance of 2 feet is required between the bottom of the excavated Bioretention area and the seasonally high ground water table.", "page_or_section": "BR-3, BR.9" }, { "field": "design_parameters.shwt_separation_inches", "excerpt": "a minimum vertical distance of 2 feet must be provided between the bottom of the Permeable Pavement installation ... and the seasonal high water table.", "page_or_section": "PP feasibility, PP.9" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Soil Media = 18\" min. - Section BR-4.8 & Table BR-1", "page_or_section": "Figure BR-2 schematic, BR.4" }, { "field": "design_parameters.bioretention_media_depth_min_inches", "excerpt": "Minimum Filter Media Depth 18 in.", "page_or_section": "Residential Rain Garden design table, BR.54" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Use the Infiltration Design for tested infiltration rates > 0.5 in. per hr.", "page_or_section": "Table BR-1 Level 2, BR.5" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Underdrains are needed if the measured permeability of the underlying soils is less than 0.5 inches per hour.", "page_or_section": "BR-3, BR.9" }, { "field": "design_parameters.swale_longitudinal_slope_percent", "excerpt": "Grass Swale ... Max Slope5 ... 4%17", "page_or_section": "Table 3.6 BMP Screening, page 67" }, { "field": "design_parameters.bioretention_ponding_depth_inches", "excerpt": "Ponding Depth = 6\" – 18\" - Section BR-4.6", "page_or_section": "Figure BR-2, BR.4 (range only; no single value assigned)" } ], "extraction_quality": { "confidence": "high", "needs_human_review": false, "review_notes": null, "fields_not_found": [] }, "source": { "document_url": "https://apps.dep.wv.gov/Documents/DWWM/Stormwater/Design/West_Virginia_Stormwater_Management_and_Design_Guidance_Manual_FULL_November_2012-v2.pdf", "landing_page_url": "https://dep.wv.gov/WWE/Programs/stormwater/MS4/Pages/StormwaterManagementDesignandGuidanceManual.aspx", "retrieved_at": "2026-08-08T00:57:15.075Z", "original_filename": "west-virginia-manual.extraction.json" }, "design_parameters": { "wqv_depth_inches": 1, "max_drawdown_hours": 48, "shwt_separation_inches": 24, "bioretention_media_depth_min_inches": 18, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": 0.5, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": 4, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "bioretention", "constructed_wetland", "extended_detention", "green_roof", "infiltration_basin", "infiltration_trench", "permeable_pavement", "sand_filter", "swale", "wet_pond" ], "enriched_at": "2026-08-13T10:33:03.752Z", "enrich_model": "composer-2.5:run-da032df4-5d83-4f73-a63a-fca2ed1cf42a", "enrich_notes": "Runoff Reduction Method targets Treatment Volume (Tv) from a one-inch rainfall event (90th percentile). Bioretention Level 1 vs Level 2 ties media depth (1.5–2.0 ft) and 48-hour drain to runoff reduction credits (60% vs 100%). Ponding depth is stated as 6–18 in. (not a single design number). Permeable pavement 2:1 in Table 3.6 is run-on impervious area to permeable pavement area, not facility length-to-width. Dry extended detention and wet pond specs are excluded from runoff reduction chapter but referenced for peak control.", "enrich_schema_version": 2, "fields_not_found": [ "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wv-wvdoh-drainage", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/wv-wvdoh-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/wv-wvdoh-drainage.json", "document_metadata": { "jurisdiction_name": "West Virginia", "jurisdiction_level": "state", "state_code": "WV", "document_title": "WVDOH Drainage Manual 3rd Ed.", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS", "HEC-RAS", "Modified Rational Method" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "HEC-HMS", "HEC-RAS", "HY-8" ], "approved_bmp_categories": [] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "West Virginia", "page_or_section": "Title / header" }, { "field": "document_metadata.document_title", "excerpt": "WVDOH Drainage Manual 3rd Ed.", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "nage structures shall be designed for a 10-year flood (exceedence probability of 10 percent). PAGE 2-2 ADDENDUM 1 2/2012 CHA", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "ment through clearly stated reasons and rationale for specific design decisions. 3.4 RESPONSIBILITY The designer is responsible", "page_or_section": null }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Drainage facilities shall be designed to accommodate the discharge for the minimum specified design storm criteria. Table 4-2 presents the minimum criteria", "page_or_section": "Chapter 4, Section 4.3.1 / Table 4-2 Design Storm Criteria" }, { "field": "practice_mentions", "excerpt": "some roadway projects may require stormwater detention analysis. (See Chapter 10 and Chapter 9 respectively, for criteria).", "page_or_section": "Chapter 2, Section 2.4.2 Legal Considerations" }, { "field": "design_parameters.design_infiltration_rate_in_per_hr", "excerpt": "Soil permeability", "page_or_section": "Chapter 1, Section 1.3 General Drainage Considerations" }, { "field": "practice_mentions", "excerpt": "surface infiltration and storage (ponds, wetlands).", "page_or_section": "Chapter 4, Section 4.2.7 Evaluation of Runoff Factors" }, { "field": "enrich_notes", "excerpt": "9 Stormwater Management ... HEC-22, Urban Drainage Design Manual, 2009", "page_or_section": "Chapter 1, Table 1-3 List of Recommended Publications" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. WVDOH Drainage Manual 3rd Ed. (2007) with Addendum 9-23-13", "fields_not_found": [ "design_criteria.water_quality_volume_method", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://transportation.wv.gov/highways/engineering/Manuals/Drainage/WVDOH%202007%20Drainage%20Manual%20with%20Addendum%209-23-13.pdf", "landing_page_url": "https://transportation.wv.gov/highways/engineering/Pages/Manuals.aspx", "retrieved_at": "2026-08-11T17:59:28.857Z", "original_filename": "wv-wvdoh-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [], "enriched_at": "2026-08-13T10:35:54.022Z", "enrich_model": "composer-2.5:run-ba932616-ce40-41ef-96eb-089443334473", "enrich_notes": "Provided excerpts cover Chapters 1–4 (introduction, policy, documentation, hydrology) plus TOC references to Chapter 9 Stormwater Management; no Chapter 9 BMP design text is included. Atlas WQv method is null and approved BMPs none. Manual cites HEC-22 (2009) for storm drainage and stormwater management; karst-adjusted hydrology (Table 4-1) and design storm return periods (Table 4-2) are present but are not WQv depth or SCM sizing criteria.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wi-wisdot-drainage", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wi-wisdot-drainage/", "data_url": "https://stormwateratlas.com/data/manuals/wi-wisdot-drainage.json", "document_metadata": { "jurisdiction_name": "Wisconsin", "jurisdiction_level": "state", "state_code": "WI", "document_title": "WisDOT FDM Chapter 13 Drainage", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [ 2, 5, 10, 25, 50, 100, 500 ], "water_quality_volume_method": null, "peak_flow_calculation_method": [ "Rational Method", "NRCS / SCS Curve Number (TR-55)", "TR-20", "HEC-HMS" ], "required_hydrologic_hydraulic_software": [ "HydroCAD", "HEC-HMS" ], "approved_bmp_categories": [ "Detention Basin" ] }, "evidence": [ { "field": "document_metadata.document_title", "excerpt": "WisDOT FDM Chapter 13 Drainage", "page_or_section": "Title / header" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "there is a 0.01 percent chance that two 100-year events can happen in back-to- back years. Since the actual time between occurre", "page_or_section": null }, { "field": "design_criteria.peak_flow_calculation_method", "excerpt": "inate with municipalities during the operational planning meeting or otherwise to inquire if new development is pending adjacent", "page_or_section": null }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "Detention Basin", "page_or_section": null }, { "field": "practice_mentions.extended_detention", "excerpt": "For projects anticipating the need for detention ponds for peak rate control only (not TS 4 or other required stormwater treatment purpose), contact the Bureau of Project Development Statewide Drainage Engineer(s) prior to design.", "page_or_section": "FDM 13-10 Section 10.1 General, page 14" }, { "field": "practice_mentions.extended_detention", "excerpt": "For stormwater ponds or features required for treatment reference this subsection for the hydraulic methods described within but also reference FDM Chapter 10 and inquire with the Bureau of Technical Services Statewide Stormwater Engineer for the appropriate pollutant removal requirements.", "page_or_section": "FDM 13-10 Section 10.1 General, page 14" }, { "field": "design_parameters (context)", "excerpt": "Stormwater Facilities - - Customary Method - -", "page_or_section": "Table 5.1 Hydrologic Method Selection, page 8" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Heuristic agency extract from prepared text. WisDOT FDM Chapter 13 Drainage — Section 13-10 Hydrology Pipeline excerpt repair removed 1 unlocated citation(s).", "fields_not_found": [ "design_criteria.water_quality_volume_method", "document_metadata.jurisdiction_name" ] }, "source": { "document_url": "https://wisconsindot.gov/rdwy/fdm/fd-13-10.pdf", "landing_page_url": "https://wisconsindot.gov/pages/doing-bus/eng-consultants/cnslt-rsrces/rdwy/fdm.aspx", "retrieved_at": "2026-08-11T17:59:10.591Z", "original_filename": "wi-wisdot-drainage.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "extended_detention" ], "enriched_at": "2026-08-13T10:33:57.254Z", "enrich_model": "composer-2.5:run-05f74bbe-00ed-450d-b372-b1437d72185a", "enrich_notes": "Provided corpus is FDM 13-10 Hydrology (design frequency, peak runoff methods, drainage area). Stormwater ponds for treatment defer pollutant requirements to FDM Chapter 10 and Bureau of Technical Services Statewide Stormwater Engineer; detention for peak rate control requires coordination with BPD Statewide Drainage Engineers. No explicit SCM dimensional or WQv depth criteria in these excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wi-dnr-1001", "processed_at": "2026-08-17T03:19:55.626Z", "detail_url": "https://stormwateratlas.com/wi-dnr-1001/", "data_url": "https://stormwateratlas.com/data/manuals/wi-dnr-1001.json", "document_metadata": { "jurisdiction_name": "Wisconsin Department of Natural Resources", "jurisdiction_level": "state", "state_code": "WI", "document_title": "Wet Detention Pond (1001) — WDNR Technical Standard", "version_or_edition": "10/07", "adoption_or_effective_date": "2007-10", "last_revised_date": "2007-10", "relationship_to_state_manual": "independent", "issuing_agency_category": "dep_deq" }, "design_criteria": { "design_storm_return_periods_years": [ 1, 2, 10, 100 ], "water_quality_volume_method": "Permanent pool surface area sized from post-construction peak outflow during the 1-yr, 24-hour design storm and target particle settling velocity (Equation 1; 80%/60%/40% TSS via 3/6/12 micron particles). Active storage volume above the permanent pool sized with a hydrograph method (TR-55 / App. B) for the 1-yr, 24-hour storm. Demonstrates TSS reduction and peak-flow control per NR 151.12.", "peak_flow_calculation_method": [ "NRCS Technical Release 55 (TR-55) hydrograph method", "Runoff curve numbers (TR-55; cropland Table 1)" ], "required_hydrologic_hydraulic_software": [ "SLAMM", "P8", "DETPOND" ], "approved_bmp_categories": [ "Wet Detention Pond" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "Wisconsin Department of Natural Resources Technical Standard", "page_or_section": "Page 1, header" }, { "field": "document_metadata.state_code", "excerpt": "Wisconsin Department of Natural Resources", "page_or_section": "Page 1" }, { "field": "document_metadata.document_title", "excerpt": "information in “The Design and Use of Detention Facilities for Stormwater Management Using DETPOND” by R. Pitt and J. Voorhees (2000).", "page_or_section": "p. 10" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "Wisconsin Department of Natural Resources Technical Standard", "page_or_section": "Page 1" }, { "field": "design_criteria.design_storm_return_periods_years", "excerpt": "the elevation reached by the 2-yr., 24-hour storm event. E. For synthetic liners, follow the manufacturers’ recommendations for installation.", "page_or_section": "p. 17" }, { "field": "design_criteria.water_quality_volume_method", "excerpt": "States Department of Agriculture, Natural Resources Conservation Service, Washington, D.C. 1986. NRCS Bulletin No. WI-210-8-16 (Sept. 12, 1988) amended the TR-55 routing graph for Type II storms to include flows outside the original range.", "page_or_section": "p. 11" }, { "field": "practice_mentions.wet_pond", "excerpt": "Appendix A—Calculation of Preliminary Permanent Pool Surface Area for TSS Reduction", "page_or_section": "Appendix A, page 10" }, { "field": "design_parameters.wqv_depth_inches", "excerpt": "Table 2 provides a summary of the 1-year, 24-hour rainfall totals", "page_or_section": "Appendix B, page 12" }, { "field": "design_parameters.permanent_pool_depth_inches", "excerpt": "Appendix C—Pond Geometry", "page_or_section": "Appendix C, pages 14–16 (no depth values in provided text)" }, { "field": "design_parameters.max_drawdown_hours", "excerpt": "Approximate Detention Basin Routing for Type II Storms", "page_or_section": "Appendix B, page 11 (routing curves only; no drawdown hours)" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Narrow WDNR Technical Standard 1001 for wet detention ponds only — not a full statewide stormwater design manual. Explicitly excludes flood-control design; local authorities may require peak control beyond the 2-yr, 24-hour storm. SLAMM/P8/DETPOND are approved optional models, not mandated for every design. Companion standards (1002–1004, 1064) and NR 151 govern broader post-construction requirements. Pipeline excerpt repair removed 9 unlocated citation(s).", "fields_not_found": [ "design_criteria.approved_bmp_categories (beyond wet detention pond — this standard covers only one practice)", "document_metadata.jurisdiction_level", "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software", "design_criteria.approved_bmp_categories" ] }, "source": { "document_url": "https://dnr.wisconsin.gov/sites/default/files/topic/Stormwater/1001WetDetentionPond.pdf", "landing_page_url": "https://dnr.wisconsin.gov/topic/Stormwater", "retrieved_at": "2026-08-08T10:16:00.000Z", "original_filename": "wi-dnr-1001.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "wet_pond" ], "enriched_at": "2026-08-13T10:33:23.115Z", "enrich_model": "composer-2.5:run-ef12b446-7eba-4633-b45d-abb8ce6319be", "enrich_notes": "WDNR Technical Standard 1001 covers wet detention ponds only. Permanent pool minimum surface area is percent of watershed by land use/impervious (Appendix A) for 80%/60% TSS via particle settling; active storage above permanent pool uses TR-55/App. B hydrograph routing for the 1-year, 24-hour storm. County 1-yr 24-hr rainfall totals are 1.9–2.6 in (Tables 2–3). Synthetic/clay liners (Types A–C); liner must extend above permanent pool to the 2-year, 24-hour elevation. Provided Appendix C pond geometry pages contain no extractable numeric geometry in this corpus.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } }, { "slug": "wy-wydot-field", "processed_at": "2026-08-17T03:19:55.630Z", "detail_url": "https://stormwateratlas.com/wy-wydot-field/", "data_url": "https://stormwateratlas.com/data/manuals/wy-wydot-field.json", "document_metadata": { "jurisdiction_name": "Wyoming Department of Transportation (WYDOT)", "jurisdiction_level": "state", "state_code": "WY", "document_title": "Pollution Controls and Best Management Practices for Storm Water During Construction — Field Guide", "version_or_edition": null, "adoption_or_effective_date": null, "last_revised_date": null, "relationship_to_state_manual": "independent", "issuing_agency_category": "dot" }, "design_criteria": { "design_storm_return_periods_years": [], "water_quality_volume_method": null, "peak_flow_calculation_method": [], "required_hydrologic_hydraulic_software": [], "approved_bmp_categories": [ "Grading Techniques (Surface Roughening, Diversion Ditches, Slope Drains, Ditch Checks, Rock Check Dike, Vegetative Buffers)", "Perimeter Control and Barriers (Silt Fence, Earthen Berm, Inlet Protection, Sediment Traps)", "Vehicle Tracking Control Pads", "Reclamation (Erosion Control Blankets, Hydraulic Mulch, Dry Mulch)", "Materials, Equipment and Waste Handling (Bulk Storage, Equipment Management, Spill Prevention and Response)", "Waste Management (Concrete Washout Areas, Saw Cutting, Portable Toilets)" ] }, "evidence": [ { "field": "document_metadata.jurisdiction_name", "excerpt": "WYOMING DEPARTMENT OF TRANSPORTATION", "page_or_section": "Title Page" }, { "field": "document_metadata.jurisdiction_level", "excerpt": "This WYDOT Pocket Field Guide has been designed and developed to be used in the field for storm water management during construction", "page_or_section": "Use of This Field Guide" }, { "field": "document_metadata.state_code", "excerpt": "In Wyoming, the Department of Environmental Quality (DEQ) implements the storm water program under the Wyoming Pollutant Discharge Elimination System (WYPDES).", "page_or_section": "Wyoming Storm Water Permit for Construction Activities" }, { "field": "document_metadata.document_title", "excerpt": "Pollution Controls and Best Management Practices for Storm Water During Construction FIELD GUIDE", "page_or_section": "Title Page" }, { "field": "document_metadata.relationship_to_state_manual", "excerpt": "This Field Guide includes: WYDOT specifications from the Standard Specifications for Road and Bridge Construction, WYDOT standard details from the Temporary Erosion Control Measures for Storm Water Pollution Prevention – Standard Plan Sheets.", "page_or_section": "Use of This Field Guide" }, { "field": "design_criteria.approved_bmp_categories", "excerpt": "BMPS FOR EROSION CONTROL GRADING TECHNIQUES... BMPS FOR SEDIMENT CONTROL PERIMETER CONTROL AND BARRIERS... VEHICLE TRACKING CONTROL PADS... BMPs FOR RECLAMATION... BMPs FOR MATERIALS, EQUIPMENT AND WASTE HANDLING... WASTE MANAGEMENT", "page_or_section": "Table of Contents" }, { "field": "practice_mentions.swale", "excerpt": "Ditch Checks are designed to provide erosion control within man-made storm water conveyances such as ditches, channels, and swales.", "page_or_section": "DITCH CHECKS, pages 17-17" } ], "extraction_quality": { "confidence": "medium", "needs_human_review": true, "review_notes": "Narrow construction-field pocket guide for BMP installation/inspection, not a hydrologic design manual. No design storm return periods, water quality volume method, peak-flow methods, or required modeling software appear in the text. Source PDF URL filename includes '4-6-11' (likely 2011-04-06) but no edition or effective date is stated in the extracted text, so dates were left null.", "fields_not_found": [ "document_metadata.version_or_edition", "document_metadata.adoption_or_effective_date", "document_metadata.last_revised_date", "design_criteria.design_storm_return_periods_years", "design_criteria.water_quality_volume_method", "design_criteria.peak_flow_calculation_method", "design_criteria.required_hydrologic_hydraulic_software" ] }, "source": { "document_url": "https://www.dot.state.wy.us/files/live/sites/wydot/files/shared/Construction/WYDOT%20Storm%20Water%20Field%20Guide%204-6-11.pdf", "landing_page_url": "https://www.dot.state.wy.us/home/engineering_technical_programs/manuals_publications.html", "retrieved_at": "2026-08-08T10:16:22.022Z", "original_filename": "wy-wydot-field.pdf" }, "design_parameters": { "wqv_depth_inches": null, "max_drawdown_hours": null, "shwt_separation_inches": null, "bioretention_media_depth_min_inches": null, "bioretention_ponding_depth_inches": null, "permeable_pavement_storage_depth_inches": null, "design_infiltration_rate_in_per_hr": null, "permanent_pool_depth_inches": null, "ed_drain_time_hours": null, "length_to_width_ratio": null, "wetland_detention_hours": null, "swale_bottom_width_inches": null, "swale_longitudinal_slope_percent": null, "green_roof_media_depth_inches": null, "green_roof_slope_percent": null, "mtd_verification_program": null, "practice_mentions": [ "swale" ], "enriched_at": "2026-08-13T10:36:26.942Z", "enrich_model": "composer-2.5:run-4f07f715-b490-4976-b47c-47e3336aa84c", "enrich_notes": "WYDOT construction stormwater field guide focused on temporary erosion/sediment BMP installation and inspection (grading, perimeter controls, tracking pads, reclamation, spill/waste). No post-construction SCM sizing, WQv method, infiltration design rates, or canonical treatment practice design criteria appear in the excerpts.", "enrich_schema_version": 2, "fields_not_found": [ "wqv_depth_inches", "max_drawdown_hours", "shwt_separation_inches", "bioretention_media_depth_min_inches", "bioretention_ponding_depth_inches", "permeable_pavement_storage_depth_inches", "design_infiltration_rate_in_per_hr", "permanent_pool_depth_inches", "ed_drain_time_hours", "length_to_width_ratio", "wetland_detention_hours", "swale_bottom_width_inches", "swale_longitudinal_slope_percent", "green_roof_media_depth_inches", "green_roof_slope_percent", "mtd_verification_program" ] } } ] }