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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

2010 Annual Report
Download report (PDF).

RWSP 2010 annual report

September 2011

Executive summary

The Regional Wastewater Services Plan (RWSP) 2010 Annual Report summarizes the progress made during 2010 in implementing the plan’s major programs and projects. The report is presented in accordance with the RWSP reporting policies outlined in Ordinance 15384 and King County Code 28.86.165 and is the 11th RWSP annual report that the Wastewater Treatment Division (WTD) has prepared.

Highlights of RWSP implementation in 2010 include the following:

  • Significant progress was made on the Brightwater Treatment System, including starting equipment and system testing at the treatment plant and completing the conveyance system’s West Tunnel.
  • National Pollutant Discharge Elimination System (NPDES) permit applications for the Brightwater Treatment Plant and Brightwater Reclaimed Water were submitted to the Washington State Department of Ecology (Ecology).
  • Progress was made on six RWSP conveyance system improvement projects in various stages of project development, design, or construction.
  • The King County Department of Natural Resources and Parks recommended four projects to control combined sewer overflows in Puget Sound.
  • The Lower Duwamish Waterway Group, which consists of King County, the City of Seattle, the Port of Seattle, and the Boeing Company, completed and issued the Lower Duwamish Waterway Draft Final Feasibility Study for public comment.
  • Approximately 119,000 wet tons of biosolids were produced at South and West Point treatment plants, all of which was recycled and used beneficially as a fertilizer and soil amendment for forestry and agricultural applications or used to make compost.
  • Over 300 million gallons of reclaimed water was produced at the South, West Point, and Carnation treatment plants and used for landscape irrigation, wetland enhancement, and industrial processes.