King Street odor control

Completed fall 2009

The bulk of the King Street Odor Control Facility is located underground, only an air vent stack and a small electrical building are visible above ground. The above ground structures were designed to compliment the design features of the near by Weller Street Bridge (located south of site). The King Street Station (external link) is located directly north of the site. View more project photos.


Cross section of the odor control facility.

The King County Wastewater Treatment Division has completed construction of the King Street Odor Control Facility. The new odor control facility will reduce corrosive, odor-causing gases in the Elliott Bay Interceptor, a major wastewater conveyance pipe beneath Occidental Avenue and Second Avenue South in Seattle, and address a long-standing odor nuisance for the public.

How odor is controlled

The new odor control facility is equipped with strong fans and odor control equipment that will pull foul smelling gases out of the existing sewer pipe and transport them to an odor “scrubber”. Gases in the “scrubber” then pass through a carbon filter which removes odor causing compounds. The compounds are absorbed by the carbon and the cleaned air is released to the environment.

Project schedule

Construction began spring 2008 and was completed fall 2009.

King County worked with the following organizations throughout the design and construction process:

• City of Seattle
• Pioneer Square Preservation Board
• Washington State Department of Transportation
• Washington State Public Stadium Authority
• Amtrak

More information

• View project library for past project updates, news releases and graphics.