Achieving Brightwater’s air quality standards remains a priority for King County’s Wastewater Treatment Division. Odor monitoring has confirmed that the plant is achieving permit requirements.

Air quality standards go beyond the public’s ability to detect nuisance odors. King County measures Brightwater’s 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.

The diagram shows air going through 3 processes, then through a pipe and dispersed into the air. There are no odors past the property line.

To learn about how odor control works, download the Brightwater odor control fact sheet .

Brightwater 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. We are proud to report that there have not been air quality or odor issues at the Brightwater Treatment Plant. For more information about this Board, please contact BW.airboard@kingcounty.gov.