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Project update

August 3, 2018

Drilling on West Galer expected to wrap up in mid-August; annual CSO report posted

King County’s contractor expects to complete the current phase of work on West Galer Street by August 16. The contractor is installing exploratory wells and addressing any soil loss along the pipeline. After work is complete, the County’s geotechnical consultant will summarize the work and provide recommendations for continued monitoring. We will share this information with the community when it is available.

Monitoring of the surface, groundwater, noise, and vibration will continue for the remainder of the work on West Galer.

For more information, view project update .

In July 2018, King County’s Wastewater Treatment Division released the 2017 Annual CSO and Consent Decree Report.

Combined Sewer Overflows (CSOs) in King County exist in older Seattle neighborhoods like Magnolia, where one set of pipes carries both sewage and stormwater. When heavy rains fill the pipes, excess flows are released through a permitted outfall into Puget Sound. Once it is back in operations this fall, King County’s Magnolia Wet Weather Storage Facility will help reduce CSOs from the outfall off 32nd Avenue West to no more than one per year on a long-term average.

King County has provided regulators with a supplemental compliance plan and updates during the Magnolia remediation project. You can find a summary and list of CSOs in 2017 in the annual report .

Recent updates

system overview, including alignment of pipeProject overview map

Magnolia Wet Weather Storage FacilityThe Magnolia Wet Weather Storage Facility at Smith Cove is designed to store excess flows of stormwater and sewage. The facility’s 1.5 million-gallon underground storage tank will help keep sewage and stormwater out of Puget Sound during storms.

King County is Protecting our Waters

This project is part of King County’s Protecting our Waters program to prevent pollution caused by excess stormwater in the sewer system on rainy days.

Combined sewer overflows (CSOs) are relief points in older sewer systems that carry sewage and stormwater in the same pipe. When heavy rains fill the pipes, CSOs release sewage and stormwater into rivers, lakes, or Puget Sound.

King County and the City of Seattle are working together to control CSOs and keep sewage and stormwater out of local waterways.

construction phase

Who do I contact?

Monica Van der Vieren until April 8:

24-hour construction hotline: 206-205-5969

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Project location


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