Milwaukee at night

About Us

Protecting public health and the drinking water supply for millions of people takes the expertise of hundreds of specially skilled and dedicated employees. MMSD is highly regarded nationally as a leader in wastewater treatment, flood management, green infrastructure, and much more.

A recipient of the U.S. Water Prize and many other awards, the District is most proud of its record of 98.4%, since 1994, for capturing and cleaning wastewater from 28 communities in a 411 square mile area. Many metropolitan areas struggle to capture and clean the national goal of 85% of all the rain and wastewater that enters their sewer systems.

MMSD is a regional government agency that provides water reclamation and flood management services for about 1.1 million people in 28 communities in the Greater Milwaukee Area.


We serve 411 square miles that cover all, or segments of, six watersheds. Established by state law, the District is governed by 11 commissioners with taxing authority.


Besides our core responsibilities, we also create and take care of:


Milorganite Fertilizer
  • Water Quality Research
  • Household Hazardous Waste
  • Medicine Collection
  • Rain Barrels
  • Green Infrastructure
  • GreenseamsĀ®
  • Sustainability
  • Planning
  • Engineering
  • Laboratory Services
  • Industrial Waste Monitoring

MMSD Service Area Map

(District Boundary and Combined Sewer Area)

MMSD Serves these 28 communities in Wisconsin:

Bayside, Brookfield, Brown Deer, Butler, Caledonia, Cudahy, Elm Grove, Fox Point, Franklin, Germantown, Glendale, Greendale, Greenfield, Hales Corners, Menomonee Falls, Menomonee River Hills, Mequon, Milwaukee, Muskego, New Berlin, Oak Creek, River Hills, Saint Francis, Shorewood, Thiensville, Wauwatosa, West Allis, West Milwaukee, and Whitefish Bay.

*Data for the Combined Sewer Area is provided by the City of Milwaukee and represents the best information currently available.