City of Seattle Public Utilities, Combined Sewer System

We invite public comment on the resissuance of permit for City of Seattle Combined Sewer System. The proposed permit authorizes the intermittent discharge of combined wastewater and stormwater into Lake Washington, Lake Washington Ship Canal, Lake Union, Union Bay, Portage Bay, Salmon Bay, Elliot Bay, Duwamish Waterwater, Longfellow Creek, and Puget Sound.

You may view the Draft Permit and Draft Fact Sheet or view other Permit Documents at the Water Quality Permitting and Reporting Information System (PARIS) database.

Background

We regulate wastewater released from municipalities and industries using the National Pollutant Discharge Elimination System (NPDES) Wastewater Discharge Permit. This permit regulates wastewater that goes directly into lakes, rivers, Puget Sound, or the ocean (surface water). All wastewater must be treated before it goes into surface water to protect human health and aquatic life. Learn more about water quality individual permits.