Holiday closure Monday May 28: Most county offices will be closed in observance of Memorial Day.

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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

In 2011, King County is beginning construction on a project to replace a 75-year-old wood stave pipe that extends across the Lake Washington Ship Canal. The new pipe will replace a 36-inch-diameter sewer pipe that was installed in 1935 and currently conveys up to 60 million gallons a day of wastewater across the canal.

Barton Street Pump Station upgrade

The county is upgrading this pump station to meet current design and safety standards. Improvements include a new emergency generator system, larger pumps, upgraded electrical system, and replacement of other associated equipment.

Fremont Siphon replacement  

The county is beginning preliminary design on a project to replace the Fremont Siphon, which has been in service for more than 100 years

Interbay Pump Station 

In January 2011, construction started on a project to replace pumping equipment and aging electrical systems at this critical pump 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 evaluate the condition of the North Beach Force Main, installed in 1963.

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 2011, the county is moving forward with environmental review, 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