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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

Treatment process

The Brightwater Plant is an advanced treatment facility that uses a membrane bioreactor system. By combining standard biological wastewater treatment with membrane filters, the process produces higher quality water that is seven to ten times cleaner than typical secondary treated wastewater.

Process diagram and dataOdor control | Air Quality Advisory Board | Permit | Quick facts | Resource recovery

View more photos (external link, Flickr).

Process diagram and data

Odor control at Brightwater - meeting community expectations and permit requirements

Achieving Brightwater’s air quality standards remains a top priority for King County’s Wastewater Treatment Division. Since September 2011, when the treatment plant began operation, it has operated continuously without generating odors. Odor monitoring has confirmed that the plant is achieving the “no odor” standards agreed to in our permits.

Brightwater is establishing itself as a good neighbor, and air quality standards go beyond the public’s ability to detect nuisance odors. King County measures Brightwater’s air quality performance using equipment put in place to detect emissions of ammonia and hydrogen sulfide, or H2S, which produces the unpleasant “rotten egg” smell typically associated with sewage.

Odor control at Brightwater 

Learn more: download Brightwater Odor Control fact sheet (pdf, June 2014).

People can report odor concerns 24/7 by calling 206-263-9500.

Air Quality Advisory Board

The Brightwater Air Quality Advisory Board was formed to advise the county on any corrective actions necessary to achieve our commitment to no detectable odors at the property boundary of the Brightwater Treatment facilities or beyond. Learn more.

Contact us

24 hour emergency and odor reporting: 206-263-9500
Administration: 206-263-9465 

22505 State Route 9 S.E.
Woodinville, WA 98072-6010;
Directions and map 

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