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South Plant, located in Renton, is part of King County’s regional wastewater treatment system.

South Plant treats wastewater from homes and businesses coming from cities located east and south of Lake Washington. Approximately 90 million gallons a day (mgd) of wastewater is treated at this facility during the dry months and up to about 300 mgd flows can be treated during the rain/storm season.

South Plant offers tours for visitors of all ages.