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

Regional Wastewater Services PlanOver 40 years of clean water

For more than 40 years, King County has protected water quality in the Puget Sound region by providing wastewater treatment services to King, Pierce, and Snohomish counties.

The Problem -- Population GrowthIn the 1990s, flow estimates based on projected population growth estimates in King County's wastewater service area indicated that King County's regional wastewater treatment system would run out of capacity by 2010 (check out the tutorial). To ensure the continuation of high quality wastewater treatment services in the future, King County carried out an intensive planning effort, involving numerous elected officials, representatives from local sewer agencies, organizations and individuals from around the region. The Regional Wastewater Services Plan (RWSP) resulted from these efforts, which was adopted by the King County Council in November 1999 via Ordinance 13680.

More about the RWSP