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Project update

November 17, 2017

Demolition complete; construction coming soon

Read the latest project newsletter for more information about:

  • Completed demolition and site preparation
  • What to expect between now and early 2018
  • King County’s work with Maple Elementary to create art for the construction fence

Fall 2017 newsletter

Construction updates

Construction hotline: 206-205-9286 

Project description

Georgetown Wet Weather Treatment StationSite of future Georgetown Wet Weather Treatment Station at the corner of 4th Avenue South and South Michigan Street.

The Georgetown Wet Weather Treatment Station Project includes the construction of a combined sewer overflow (CSO) wet weather treatment station between the Brandon Street and South Michigan Street Regulator Stations, related pipes and a new outfall structure to release the treated water into the Duwamish River. When constructed, the station can treat up to 70 million gallons of combined rain and wastewater a day that would otherwise have discharged directly to the Duwamish without treatment during storm events.

This year, King County’s contractor completed demolition and site preparation activities. Demolition activities included removing buildings, underground structures, asphalt, and utilities. The site has been graded and prepared for treatment station construction.

This project will help clean up the Duwamish River by treating stormwater runoff and sewage during heavy rains. Right now, heavy rains can fill up our sewer pipes, sending polluted runoff and sewage through a pipe into the river. King County began on-site work in April 2017 and expects to finish construction in 2022.

Wet Weather Treatment StationWet weather treatment stations clean overflows locally on-site during heavy rain storms.


Through a competitive process, King County awarded the Treatment Station construction contract to Flatiron West Inc. Major construction will start in 2018. Through two additional competitive processes, the County will award two construction contracts to build the new pipes and outfall structure into the Duwamish River in late 2017 and early 2018. 

Project timeline


Contact us

Construction hotline:

Contact Kristine Cramer at:


 Feedback form

Sign up for email or text updates on the public involvement page.

King County partnered with Nature Consortium and Seattle Public Schools to teach 5th graders at Maple Elementary about water conservation and create art for the construction fence.

Project location


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