Metropolitan Water Reclamation District of Greater Chicago (MWRD)

The MWRD is a regional independent government agency responsible for treating wastewater and managing stormwater for the Chicago region. It is governed by a 9-member Board of Commissioners, each of whom is elected countywide in Cook County.

The MWRD’s key functions include: 

• Treating wastewater from households, businesses and industries 
• Operating water reclamation plants and large intercepting sewers 
• Providing large-scale stormwater and flood-control services, including the Tunnel and Reservoir Plan (TARP or “Deep Tunnel”)
• Partnering with communities within Cook County on stormwater and green infrastructure projects 
• Managing waterways and protecting regional water quality

The MWRD does not provide drinking water.

City of Chicago Department of Water Management (DWM)

The DWM is a municipal department of the City of Chicago focused on drinking water delivery and sewer and stormwater services within the City of Chicago. A commissioner appointed by the Mayor of Chicago leads the department.

DWM’s key functions include: 

• Providing water for Chicago and other communities within the area 
• Maintaining and repairing local water mains throughout the city 
• Maintaining local sewer systems, which carry wastewater and stormwater from streets and properties to MWRD interceptors 
• Managing stormwater within the city through maintenance of catch basins, local sewer infrastructure, and flood-mitigation efforts at the neighborhood level

DWM does not treat wastewater; its municipal sewers flow into larger MWRD sewers that carry wastewater to MWRD treatment plans.

Collaboration between the MWRD and DWM

The MWRD and DWM share the goal of reducing flooding and collaborate on flood control work within the city of Chicago, including green infrastructure and sewer improvement projects.

Summary: 

• The MWRD handles wastewater treatment and stormwater management for Cook County. 
• DWM handles drinking water, local sewers and stormwater management within the City of Chicago. It also sells water to many suburbs. 
• Both agencies are interconnected: DWM collects wastewater and stormwater through local sewers and the MWRD receives and treats wastewater and stormwater through its regional system.