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King County’s Vashon Treatment Plant recognized for perfect permit compliance


King County’s Vashon Treatment Plant earned the prestigious “Outstanding Performance Award” from the state Department of Ecology for perfect compliance with permit conditions in 2014.


The Washington State Department of Ecology honored King County’s Vashon Treatment Plant with an “Outstanding Performance Award” for perfect compliance with all permit conditions in 2014.

The Vashon Treatment Plant is among 127 wastewater treatment plants statewide that received the recognition. To earn the award, the plant had to pass all environmental tests, collect and analyze all required samples, complete reports, and operate with no violations of any kind.

The plant also had to meet the overall demands of its National Pollutant Discharge Elimination System (NPDES) permit under the federal Clean Water Act and the state’s Water Pollution Control Law.

The Vashon Treatment Plant began operating in 2007 to serve about 1,100 people who live and work within the Vashon Sewer District. The plant treats about 180,000 gallons of wastewater a day, with a capacity to handle up to 1.4 million gallons during storms.

Additional information about the Vashon Treatment Plant is available online.