For questions about the Wastewater Treatment Division Web site, please send an e-mail message or contact us at:
King Street Center 201 S. Jackson St., Suite 505 Seattle, WA 98104-3855 Phone: 206-684-1280 Fax: 206-684-1741 Telecommunication device for the deaf (TTY): 711
Get Directions to our office location in Seattle, Washington.
Welcome to the Carnation Treatment Plant, located at 4405 Larson Avenue, in the City of Carnation, Washington.
The plant serves the City of Carnation as part of King County's regional system that treats wastewater for about 1.5 million people in the Puget Sound region. The collection system, owned and maintained by the City of Carnation (external link), delivers sewage to the plant from residential and commercial customers.
Carnation Wastwater Treatment System, May 2008 (1.6MB). Where does it go after you flush, brush or do the dishes? A step-by-step overview of the Carnation Wastewater Treatment System. Backside of handout: Let's Talk Trash - what belongs in the trash can and not the toilet or drain.
Carnation Sewer System Owner's Manual is now available to download (.PDF file, 934KB). This brochure provides sewer tips (including care of the candy cane-shaped air vent in your yard and what is appropriate to put in your toilet and drain) and information on household hazardous waste disposal.