South Treatment Plant
South Treatment Plant, also referred to as South Plant, is located in Renton and is part of King County's regional wastewater treatment system. South Plant began operations in 1965.
October 2023 Update
Thank you for your survey feedback! We appreciate all the responses we received on the South Treatment Plant Near Neighbor Survey and are reviewing your feedback. We will use the survey results to give you information that matters to you and your community. Stay tuned for an update on the survey results later this winter.
Want to learn about our wet weather preparation, read here: Ready for the Next Rainy Season? The Work to Shore Up Clean Water Systems Begins Now. (Clean Water stories)
View the Winter 2023 newsletter to learn more about how South Plant protects public health and the environment, turns waste into valuable resources, and offers education and training programs to the community.
South Plant treats wastewater for about 839,000 people living in Auburn, Kent, Renton, Bellevue, Issaquah, and Sammamish, 24 hours a day, 365 days a year. During the dry months, about 90 million gallons per day of wastewater gets treated. About 300 million gallons per day can be treated during the rain/storm season. South Plant also recovers valuable resources from the treatment process, including recycled water, biogas, and Loop biosolids.
24 hour emergency and odor reporting: 206-263-1760
1200 Monster Road S.W.
Renton, WA 98057
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