City of Grand Rapids
Stormwater Standards Manual
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Grand Rapids Stormwater Standards Manual Apr 2021. Pipeline excerpt repair removed 2 unlocated citation(s).
Fields not found in document: document_metadata.adoption_or_effective_date, design_criteria.required_hydrologic_hydraulic_software, document_metadata.state_code, document_metadata.last_revised_date
Other manuals in Michigan: City of Ann Arbor, City of Detroit, City of Flint, City of Lansing, Michigan, Michigan, Wayne County
Document Metadata
Jurisdiction level
City
“City of Grand Rapids”
Cover
State
Not found in document
No evidence cited
Version / edition
Rev. 04.29.2021
“Rev. 04.29.2021”
Header
Adoption / effective date
Not found in document
No evidence cited
Last revised date
Not found in document
No evidence cited
Relationship to state manual
independent
“Stormwater Ordinance Chapter 32 / Chapter 67”
Purpose
Design Criteria
Design storm return periods (years)
2-year, 100-year
“2-year, 24-hour / 100-year storm”
Channel Protection / Flood Control
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.
“Treat the runoff generated from 1 inch of rain / "first flush"”
Water Quality
Peak flow calculation method(s)
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
“Channel Protection / Flood Control performance standards”
Part IV / Table 1
Hydrologic/hydraulic software
Not found in document
No evidence cited
Approved BMP categories
Infiltration BMPs, Detention / retention for channel protection, Structural BMPs (Green Book / Red Book specs), Water quality treatment BMPs
“infiltration BMPs / Structural Best Management Practices”
Design Process / Green Book