South Treatment Plant

Located in Renton, South Treatment Plant (South Plant) began operating in 1965. South Plant features a 1.5-acre demonstration farm, CitySoil, that produces more than 5,000 pounds of food for a local foodbank. South Plant is our most visited facility, hosting robust on-site educational programming for school groups and plant tours. The facility is also host to a septage disposal facility for commercial haulers. South Plant treats an average of 90 million gallons of wastewater per day from communities in Auburn, Bellevue, Issaquah, Kent, Renton, and Sammamish.

South Plant StoryMap

Are you a wastewater nerd like us? Itching to learn about all the ins and outs of how South Plant operates and benefits the community? We have put together an interactive tool that allows you to do just that.

Visit the South Plant StoryMap to learn about the history of our plant, the workforce that runs it, the way the plant interacts with the community, and more!