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The Carnation Treatment Plant, located in the City of Carnation, serves about 2,000 people in Carnation’s urban growth area, with capacity to serve up to 4,000 in 2030.

The plant is part of King County's regional system. At design capacity, the plant is expected to treat 480,000 gallons of wastewater a day. The collection system, owned and maintained by the City of Carnation , delivers sewage to the plant from residential and commercial customers.

In addition to the reclaimed water, the plant has been designed with numerous “green” features that minimize impacts on the environment, conserve resources and maximize energy efficiency.

banner at top of spring 2022 newsletter displaying aerial view of treatment plant and the nearby Snoqualmie RiverView our Spring 2022 newsletter .

aerial view of the Carnation Treatment PlantCarnation Treatment Plant aerial view

View more photos on our Flickr site .

Contact us

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

4405 Larson Ave.
Carnation, WA 98041

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