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King Street Center
201 S. Jackson St., Suite 500
Seattle, WA 98104-3855
Phone: 206-684-1280
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

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Staff Contacts

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

Seattle projects

Ballard Siphon replacement

King County is continuing construction in 2012 on a project to build a new 84-inch siphon pipeline between the Ballard and Interbay areas of Seattle, replacing a 75-year-old wood stave pipe now beneath the Lake Washington Ship Canal.

Barton Street Pump Station upgrade

In 2012, King County will start construction to upgrade this pump station to meet current design and safety standards. Improvements will include a new emergency generator system, larger pumps, and an upgraded electrical system.

Carkeek Pump Station and CSO Treatment Facility improvements

Planned projects for Carkeek Pump Station and Cso Treatment Facility include:

  • Carkeek Pump Station Roof Replacement Project

Fremont Siphon replacement

King County is designing a new pipeline to transport untreated wastewater from Seattle’s Fremont neighborhood to Queen Anne, and eventually to the West Point Treatment Plant in Magnolia. The current pipeline, which runs beneath the Lake Washington Ship Canal, has been in service for more than 100 years. 

Interbay Pump Station 

Construction will continue in 2012 on project to replace pumping equipment and aging electrical equipment and systems at this station near the West Point Treatment Plant in Magnolia.  

Lower Duwamish Waterway Superfund

King County will maintain involvement in the Lower Duwamish Waterway Group (external link), which is currently working with EPA and the state Department of Ecology to identify a Superfund cleanup strategy to address historically contaminated sediments in the waterway.

North Beach force main maintenance

King County is carrying out a project to assess the condition of the North Beach Force Main, installed in 1963.

North Beach outfall assessment 

King County is assessing the condition and looking at repair/replacement options for the North Beach Outfall.

Puget Sound Beach CSO Control 

Puget Sound Beaches CSO Control ProjectsKing County is making it a priority to control combined sewer overflows, or CSOs, that occur during heavy rains near popular recreation beaches in West Seattle, North Beach and Magnolia. In 2012, the county is moving forward with permitting and design of the following projects:

Sediment Management Program

This program enables King County to address sediment contamination near CSO locations in Puget Sound. The county is continuing its efforts to remove historic CSO contamination and restore habitat at locations in Elliott Bay and the Waterway.

West Point Treatment Plant improvements

Several projects are planned for West Point Treatment Plant to improve plant efficiency and operations and insure compliance with regulations.

  • Alternative disinfection system
  • Digestion system improvements
  • Energy efficient blower replacement project
  • Office annex
  • Screenings improvement project
  • Waste-to-Energy