Regulations & Permits - Washington State Department of Ecology

Information about the reissuance of 2024 Western and Eastern Washington Municipal Stormwater permits.

https://ecology.wa.gov/regulations-permits/permits-certifications/stormwater-general-permits/municipal-stormwater-general-permits/municipal-stormwater-permit-reissuance

Western Washington Hydrology Model

Western WA Hydrology Model models most hydrologic conditions for stormwater control and design.

https://ecology.wa.gov/regulations-permits/guidance-technical-assistance/stormwater-permittee-guidance-resources/stormwater-manuals/western-washington-hydrology-model

Eastern Washington Phase II Municipal Stormwater Permit

This permit regulates stormwater discharges in urbanized areas of Eastern Washington.

https://ecology.wa.gov/regulations-permits/permits-certifications/stormwater-general-permits/municipal-stormwater-general-permits/eastern-washington-phase-ii-municipal-stormwat-1

Municipal stormwater permit history

We document the development of municipal stormwater permits in Washington.

https://ecology.wa.gov/regulations-permits/permits-certifications/stormwater-general-permits/municipal-stormwater-general-permits/municipal-stormwater-permit-history

Washington Department of Transportation Municipal Stormwater Permit

Permit covers discharges from state highways and other WSDOT transportation-related facilities.

https://ecology.wa.gov/regulations-permits/permits-certifications/stormwater-general-permits/municipal-stormwater-general-permits/wsdot-municipal-stormwater-permit

Puget Small Streams study

Stormwater Action Monitoring's (SAM) receiving waters study on Puget Sound's small streams.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-status-and-trends/puget-small-streams

Mobile business stormwater source control and coordination

We're developing and testing new tools to help mobile businesses control stormwater pollution.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-source-identification/mobile-business-source-control

Lower Columbia urban streams

This monitoring is funded by the municipal stormwater permittees in Clark and Cowlitz counties.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-status-and-trends/lower-columbia-urban-streams

Sand & Gravel General Permit history

Find historical information about our Sand and Gravel General Permit.

https://ecology.wa.gov/regulations-permits/permits-certifications/sand-gravel-general-permit/sand-gravel-general-permit-history

Stormwater manuals

We develop stormwater manuals to provide stormwater permit implementation and management guidance.

https://ecology.wa.gov/regulations-permits/guidance-technical-assistance/stormwater-permittee-guidance-resources/stormwater-manuals

Guidance for contaminated water on construction sites

Information on how to manage contaminated water on construction sites.

https://ecology.wa.gov/regulations-permits/guidance-technical-assistance/stormwater-permittee-guidance-resources/contaminated-water-on-construction-sites

Paired watershed retrofit & restoration study

Stormwater Action Monitoring effectiveness study: Paired watershed retrofit and restoration study.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-effectiveness-studies/paired-watershed-retrofit-and-restoration-study

Municipal stormwater general permits

This permit covers urban areas that collect stormwater runoff in public storm sewer systems.

https://ecology.wa.gov/regulations-permits/permits-certifications/stormwater-general-permits/municipal-stormwater-general-permits

Bioretention effectiveness for 6PPD and PFAS

Treatment Effectiveness of Stormwater Facility with HPBSM for Toxic Chemicals

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-effectiveness-studies/bioretention-effectiveness-for-6ppd-and-pfas

Applying for laboratory accreditation

Learn specific details on how laboratories may seek and maintain accreditation in Washington.

https://ecology.wa.gov/regulations-permits/permits-certifications/laboratory-accreditation/applying-for-laboratory-accreditation

Longevity of biological protection using bioretention

Study about the effectiveness of bioretention soil retaining pollution over time.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-effectiveness-studies/longevity-biological-protection-using-bioretention

Agrium Kennewick Fertilizer Operations

We regulate water and hazardous waste for Agrium Kennewick Fertilizer Operations facilities.

https://ecology.wa.gov/regulations-permits/permits-certifications/industrial-facilities-permits/agrium-kennewick-fertilizer-operations

Mint Farm Electricity Cogeneration Facility

We regulate water and hazardous waste for PSE's Mint Farm electricity cogeneration facility.

https://ecology.wa.gov/regulations-permits/permits-certifications/industrial-facilities-permits/mint-farm

Specialty Minerals, Longview

We regulate water and hazardous waste at the Specialty Minerals chemical plant in Longview.

https://ecology.wa.gov/regulations-permits/permits-certifications/industrial-facilities-permits/specialty-minerals-longview

Evaluation of Best Management Practices Maintenance Conditions

Study evaluating the maintenance thresholds for select best management practices for stormwater.

https://ecology.wa.gov/regulations-permits/reporting-requirements/stormwater-monitoring/stormwater-action-monitoring/sam-effectiveness-studies/bmp-maintenance-conditions