Boston Water and Sewer Commission

2024 Stormwater Management Report

CityMassachusettsmediumNeeds review

This extraction needs human review.

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 in document: 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

Other manuals in Massachusetts: Massachusetts

Document Metadata

Jurisdiction level

municipality

“Discharges to the Boston Water and Sewer Commission’s (Commission) municipal separate storm sewer system (MS4)”
Section 1.1, Page 1-1

State

Massachusetts

“Massachusetts Department of Environmental Protection (DEP)”
Section 1.1, Page 1-1

Version / edition

2024

“2024 Stormwater Management Report”
Title Page

Adoption / effective date

Not found in document

No evidence cited

Last revised date

2024

“2024 Stormwater Management Report”
Title Page

Relationship to state manual

independent

“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.”
Section 3.5 / Section 7.5

Design Criteria

Design storm return periods (years)

Not found in document

No evidence cited

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.

“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.”
Section 3.5 On-site Retention of Stormwater, Pages 3-7 to 3-8

Peak flow calculation method(s)

Not found in document

No evidence cited

Required hydrologic/hydraulic software

Not found in document

No evidence cited

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)

“In 2024, the Commission approved installations of 301 infiltration devices.”
Section 3.5 / Table 3-4