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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.

Digester—solids biological treatmentDigester—solids biological treatment

View more photos on our Flickr site  .

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

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 BrightwaterLearn more: download Brightwater odor control fact sheet    (June 2014)

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

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.