Vashon Treatment Plant
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.
November Update: Dewatering equipment installation starting November 13, 2017
King County crews will install dewatering equipment at the Vashon Bunker Trail (BT) 1 and 2 (see map below) starting Monday, November 13. Equipment includes baker tanks to hold excess water, a diesel-powered pump and a generator that will run 24/7 while the work is being completed. No changes are expected to traffic, and one lane will remain closed between BT1 and BT3 along 103 Avenue SW.
See flier for more information.
Other construction activities
- Vashon pump stations temporary sewer discharge to manhole at the end of 96th place SW, November 29, 2017
For more information contact: Bibiana Ocheke-Ameh at 206-477-5604 or email@example.com
- Construction update: Vashon Drip Field Replacement begins in June, May 2017.
Vashon Treatment Plant site—after construction
View more photos on our Flickr site .
24 hour emergency and odor reporting: 206-263-1760
9615 S.W. 171st St.
Vashon, WA 98070
View NPDES permit
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