Reclaimed Water Program
-- formerly the Water Reuse Program

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To protect Puget Sound and help meet our region's growing need for water for people, industry, farms and fish, King County continues to produce reclaimed water.

Reclaimed water is wastewater that's treated to such a high level it can be used safely and effectively for nondrinking purposes such as landscape and agricultural irrigation, heating and cooling, and industrial processing. Reclaimed water is available year-round, even during dry summer months or when a drought strains other water resources.

King County's Regional Wastewater Services Plan -- the 30-year operating plan for our wastewater system -- calls for expanding the production and use of reclaimed water as a valuable resource. Reclaimed water has been used successfully and safely in other areas of the country and world for decades.

Reclaimed water in King County

The county's Wastewater Treatment Division has been safely using reclaimed water since 1997 at its regional treatment plants in Seattle and Renton. Two treatment plants under construction -- Carnation and Brightwater -- will be producing reclaimed water when they are operational.

Strict safety standards protect people and the environment

King County's reclaimed water meets strict Class A standards set by the state departments of Health (external link) and Ecology (external link).

Reclaimed water is highly filtered and disinfected and is tested often. It contains only trace amounts of some nutrients and dissolved chemicals. Although King County’s reclaimed water is not drinking water, it is safe for human contact—even unintentional swallowing or exposure to open cuts.

Reclaimed water is distributed through a separate set of purple pipes which makes sure reclaimed water and drinking water supplies are never mixed. Purple is the nationally designated color for marking reclaimed water pipes, hoses, pumps, and other equipment.

King County invests in research and demonstration projects that support the safe and effective use of reclaimed water in our region.

To learn more

• Overview of wastewater treatment and reuse processes
• Treatment Technologies -- Advanced Technology Demonstration Project
• Advanced treatment technology at
  • Brightwater Treatment Plant
  • Carnation Treatment Plant
• Declaration of Support for Reclaimed Water, June 2007 (PDF, 31KB); add your signature to this declaration document.
• Check out the library page for reports, fact sheets, fliers, signage, workshop handouts and news releases for the Reclaimed Water Program.
• For more information about King County's Reclaimed Water Program, contact Jo Sullivan at 206-296-8361 or by e-mail.

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For questions about the Wastewater Treatment Division Web site, please send an e-mail message. For general information about the division, contact us at:

Department of Natural Resources and Parks
Wastewater Treatment Division
201 S. Jackson St., Suite 505
Seattle, WA 98104-3855
Phone: 206-684-1280
Fax: 206-684-1741
Telecommunication device for the deaf (TTY): 711

Updated: April 7, 2008

Also of interest

Regional Wastewater Services Plan
Water Conservation Program
Water Supply in King County, Washington
Endocrine disrupting chemicals in the environment
Sustainable Building Topics