Georgetown Wet Weather Treatment Station

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The Georgetown Wet Weather Treatment Station Project includes the construction of a combined sewer overflow (CSO) wet weather treatment station, related pipes and a new outfall structure to release the treated water into the Duwamish River. 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. King County began on-site work in April 2017 and expects to finish construction in 2022.

King County’s Georgetown Wet Weather Treatment Station earned the coveted “Platinum” rating from the Institute for Sustainable Infrastructure’s Envision rating system. This is the first Platinum-awarded Envision project in Washington and recognizes the County’s commitment to sustainable communities and the environment. 

The permanent financing for this project will be provided by a combination of a loan from the U.S. Environmental Protection Agency through the Water Infrastructure Finance and Innovation Act (WIFIA), program State Revolving Fund loans, and the proceeds of bonds secured by a pledge of net sewer revenues. Interim financing ahead of certain of these permanent financing sources is being provided by the Commercial Paper Program.