Washington
Stormwater Management Manual for Western Washington
StateWashingtonhighNo
Fields not found in document: design_criteria.water_quality_volume_method
Document Metadata
Jurisdiction level
state
“Washington State Department of Ecology Water Quality Program”
Title Page
State
Washington
“Issaquah, WA”
Appendix I-B: Altering the MRs with Basin Plans, Page 199
Version / edition
2024 Edition
“2024 Stormwater Management Manual for Western Washington”
page 5
Adoption / effective date
2024-07
“July 2024”
Title Page
Last revised date
2024-07
“July 2024”
Title Page
Relationship to state manual
independent
“Prepared by: Washington State Department of Ecology”
Title Page
Design Criteria
Design storm return periods (years)
2-year, 10-year, 25-year, 50-year, 100-year
“2-year, 10-year or 100-year storm”
Glossary, Page 1312 (Storm frequency)
Water quality volume method
Not found in document
No evidence cited
Peak flow calculation method(s)
Continuous Simulation Models, Single Event Hydrograph Method, Rational method, SBUH, SCS method, NRCS Method, HSPF
“Rational method”
Glossary, page 1303
Required hydrologic/hydraulic software
WWHM, HSPF
“Precipitation Stations Used in WWHM Creation”
Table of Contents, page 30
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
“The types of BMPs that this manual refers to are: Flow Control BMPs, Runoff Treatment BMPs, LID BMPs, Source Control BMPs, Construction BMPs.”
Volume I - Chapter 1 - Page 71