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Wastewater Treatment

King County, Washington

For questions about the Wastewater Treatment Division website, please send an e-mail message or contact us at:

King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-477-5371
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

Get Directions to our office location in Seattle, Washington.

Staff Contacts

Brightwater Treatment Plant–a clean water treatment facility  

Aerial photo of Brightwater Treatment Plant
The Brightwater Treatment Plant is located northeast of Woodinville WA at the intersection of Highway 9 and 228th St SE.

 Brightwater Treatment Plant service area
Brightwater Treatment Plant service area
 (PDF), September 2011.

Welcome to the Brightwater Treatment Plant. The plant is part of King County's regional system that treats wastewater for about 1.5 million people and covers 420 square miles in the Puget Sound region. Every day Brightwater cost-effectively treats wastewater from homes, offices, schools, agencies, businesses and industries in north King County and south Snohomish County.

What's happening at Brightwater

Odor control at Brightwater

Brightwater construction:

News releases

Related information