Wastewater Treatment

The Milwaukee Metropolitan Sewerage District (MMSD) cleans billions of gallons of wastewater every year, safeguarding natural resources and protecting public health for 29 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. People often think you can flush anything down the toilet or drain, which 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, efficiently clean about 150 million gallons of water on a dry day and have the capacity to clean up to 630 million gallons a day, which can be needed when it rains.

Thanks to the deep tunnel and many other improvements, we average 2.2 overflows per year (down from 50-60) and have captured and cleaned 98.6% of all the water that's entered the regional sewer system since 1994. The national goal 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 capacities; however, the Jones Island facility consumes about 80% of the total energy use, whereas the South Shore facility consumes about 20%. The interplant pipeline interconnects the two facilities’ biosolids processes, and the Milorganite® dryers consume a lot of natural gas, which is why Jones Island consumes more power than the South Shore facility.

This page is automatically updated. The data have not been verified and may contain errors. As data are verified, MMSD reserves the right to make corrections to values as necessary. MMSD is providing this data as is and the user assumes the entire risk of use of this data.

Learn About the Various Aspects of Wastewater Treatment: