Wastewater Treatment

The Milwaukee Metropolitan Sewerage District (MMSD) cleans billions of gallons of wastewater every year, safeguarding natural resources and protecting public health for 28 communities in southeastern Wisconsin.

We treat a range of wastewater sources from industrial to surface runoff and whatever water you send down the drain at home, work, school, or church. Often people think you can flush anything down the toilet or drain, and that is not true. Learn what not to flush to protect our water, your home, and our systems.

Our two water reclamation facilities, Jones Island and South Shore, can efficiently clean about 150 million gallons of water on a dry day and 630 million gallons a day when it rains. 

Thanks to the deep tunnel and many other improvements, we average 2.3 overflows per year (down from 50-60) and have captured and cleaned 98.5% of all the water that's entered the regional sewer system since 1994. The goal nationally is to capture and clean 85% of water for more than 700 cities with systems like ours. We continue to strive for zero overflows by investing in our treatment plants, sewers and implementing green infrastructure in our region to help manage water where it falls.

MMSD’s two Water Reclamation Facilities have similar wet weather capacity; however, the Jones Island facility consumes about 80% of the total energy use, whereas the South Shore facility consumes about 20%.  This is because the two facilities’ biosolids processes are interconnected by the interplant pipeline. The Milorganite® dryers consume a lot of natural gas, which is why Jones Island consumes more power than the South Shore facility.

Learn About the Various Aspects of Wastewater Treatment: