
By Cari Simson, Stormwater Programs Director
Rain has returned to Seattle and with it, the acute awareness of the region’s pollution challenges. Recently, the Duwamish River was declared unsafe due to a sewage spill. Spills like this have repercussions for swimming, fishing and other aquatic activities and communities are not always made aware of the dangers. While this particular spill was resolved in just a day, the incident reminds us why stormwater pollution is Puget Sound’s #1 source of pollution.

The size of the Georgetown Wet Weather Treatment Plant reflects the magnitude of the stormwater pollution challenge. Photo Credit: Cari Simson / ECOSS.
At the same time, these spills underline the importance of wastewater treatment solutions. Jacobs Engineering invited ECOSS to tour the site of the upcoming King County Georgetown Wet Weather Treatment Plant with the entire design and construction team.
Located on S. Michigan Street and 4th Avenue, the Georgetown Wet Weather Treatment Plant 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.

Learn more about King County’s Georgetown Wet Weather Treatment Station here. Photo Credit: Cari Simson / ECOSS.
King County began on-site work in April 2017 and expects to finish construction in 2022. When constructed, the Georgetown station will 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. Right now, heavy rains can fill up the city’s sewer pipes, sending polluted runoff and sewage into the river, causing harm to wildlife and human health.
It was fascinating for ECOSS staff to see in-the-ground progress that shows utility investment in these types of large projects. ECOSS works with industry along the Duwamish River on innovative solutions to reduce stormwater pollution. Seeing other examples is not only inspiring, but also a great opportunity to share ideas.
Be on the lookout for news on ECOSS’ industrial-scale stormwater solutions, coming soon!
See more on how ECOSS works with industry to mitigate stormwater pollution