Reclaimed water

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.

King County is in the process of developing a Reclaimed Water Comprehensive Plan. The planning process will provide an opportunity for a regional discussion about if, how and when King County should expand its reclaimed water system beyond the existing system. The Plan is intended to provide overall programmatic guidance for King County's reclaimed water program for the next 30 years.


Reclaimed Water Sign --
We're using water wisely by irrigating with reclaimed water. Also available as pdf file (985KB)

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. The treatment plant recently completed in Carnation is producing reclaimed water. One treatment plant under construction, Brightwater, will be producing reclaimed water when it is operational.

Strict safety standards protect people and the environment

King County's reclaimed water quality 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 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.