King County Georgetown Wet Weather Treatment Station

Project Description

King County will construct a new Wet Weather Treatment Station using high-rate clarification, conveyance pipelines, and outfall structure to treat and convey combined sewer overflows prior to being discharged into the Lower Duwamish Waterway. When constructed, the station can treat up to 70 million gallons of combined rain and wastewater a day that would otherwise have discharged directly to the Duwamish without treatment during storm events. This project is designed to control two existing combined sewer overflows to meet the Washington State control standard. 

Project Benefits

• Designed to reduce over 95 percent of untreated wastewater and stormwater entering the Duwamish River by controlling two existing combined sewer overflows.
• Redevelops a Brownfields site.
• Saves King County up to $32 million from financing with a WIFIA loan compared to a bond issuance.
• Creates 1,400 jobs and job-training opportunities during design, construction, and operation.

• Georgetown Wet Weather Treatment Station (King County, Washington) (pdf) (266.02 KB)