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Capital improvement projects

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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

Wastewater tutorial

Solution -- the approved RWSP

planned system



The Regional Wastewater Services Plan was approved by the King County Council in December, 1999. The following are key features of the approved RWSP:

  • A new third treatment plant to be located somewhere in north King or South Snohomish County. This plant will provide more capacity and more flexibility for the future.
  • To reduce costs, King County will work with local sewer agencies to fix and prevent leaks that allow rain and groundwater to enter the wastewater system.
  • King County will continue to reduce combined sewer overflows in the oldest parts of the system.
  • Wastewater treatment byproducts: biosolids, methane and reclaimed water will be recycled.
  • In the future, highly treated wastewater could indirectly supplement the water supply for our growing region, leaving more fresh water in the streams for fish.

History | Current Wastewater System | The Problem
The Solution | The Future