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Many King County facilities are closed to the public. Learn how to access services remotely or while practicing social distancing guidelines.  
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Wastewater Treatment Division (WTD) and Novel Coronavirus (COVID-19)

WTD operations staff remain on the job 24/7 to ensure the region’s wastewater treatment service continues. Following the guidance of Seattle-King County Public Health, our offices are closed to the public and all facility tours are suspended until further notice. Please check back periodically for updates.

For questions about COVID-19, we encourage people to visit the Public Health – Seattle & King County website: www.kingcounty.gov/covid and subscribe to the Public Health Insider blog: www.publichealthinsider.com

The Vashon Treatment Plant, located on Vashon Island, is part of King County's regional wastewater treatment system.

It treats wastewater from homes and businesses within the Vashon Sewer District. Approximately 180,000 gallons a day of wastewater is treated at this facility. A maximum of 1.4 million gallons per day can be treated during the rain/storm season.

Vashon Treatment PlantVashon Treatment Plant site—after construction

View more photos on our Flickr site  .

Contact us

24 hour emergency and odor reporting:   206-263-1760
Administration:  206-463-7318 

Address
9615 S.W. 171st St.
Vashon, WA 98070

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