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King Street Center
201 S. Jackson St., Suite 505
Seattle, WA 98104-3855
Phone: 206-684-1280
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

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Puget Sound shoreline next to the West Point Treatment Plant, Seattle

Denny Way/Lake Union CSO Project

Completed spring 2005

Welcome to the Denny Way/Lake Union Combined Sewer Overflow Control Project.

This project is a joint effort of King County and the City of Seattle to control combined sewer overflows (CSOs) into Lake Union and Elliott Bay. CSOs are overflows of sanitary (residential and commercial) sewage and stormwater that are released into water bodies during storms.

Under way since May 2000, construction is now complete.

Dedication ceremony held Thursday, July 7, 2005

West Point NPDES permit modified to include Elliott West and Henderson/Martin Luther King CSO treatment facilities.

News Release, July 7, 2005 -- King County dedicates new Seattle facilities to control overflows of untreated stormwater, sewage

King County Wastewater Treatment Division Director Don Theiler addresses the crowd
King County Wastewater Treatment Division Director Don Theiler addresses the crowd.

After nearly 12 years of planning and more than four years of construction, the Denny Way/Lake Union Combined Sewer Overflow Control Project is complete. This joint project with the City of Seattle is one of the most significant public investment efforts undertaken by King County and the largest of all county CSO control systems.

We celebrated the project completion with a dedication ceremony Thursday, July 7, at the new Elliott West CSO Control Facility, 545 Elliott Ave. W.

We want to express our appreciation to members of the community, organizations and businesses affected by construction -- and to agencies, officials, employees and companies that supported this major effort to protect public health and the environment.

illustration of CSO Control Facility
Elliott West CSO Control Facility

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