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For Immediate Release


Josh Mogerman, NRDC, 312-651-7909; Jack Darin, Sierra Club, 312-251-1680 x112; Glynnis Collins, Prairie Rivers Network, 217-344-2371

Press Release

Serial Spillers: Groups Sue to Stop Chicago Water Regulators from Polluting the Chicago River

MWRD's illegal sewage discharges mucking waterways from Chicago to Gulf of Mexico

A coalition of conservation groups have sued to stop the Metropolitan Water Reclamation District (MWRD) from dumping raw sewage mixed with stormwater, as well as algae-fueling pollution, into the Chicago River system. Effluent from MWRD’s sewage treatment plants and combined sewer overflow pipes regularly violate Clean Water Act standards in the River, impacting downstream waters from Chicago all the way to the Gulf of Mexico according to the suit.

“Keeping raw sewage out of our waters is the District’s core responsibility,” said Ann Alexander, Senior Attorney with the Natural Resources Defense Council. “Yet the problem continues unabated, even after three decades and billions of taxpayer dollars. Chicagoland shouldn’t have to wait any longer for the District to do its job right.”

NRDC, Sierra Club and Prairie Rivers Network filed a federal lawsuit today in the Northern District of Illinois over the regional water treater’s pollution problem. The suit points to discharges of pollution from treatment plants that regularly violate federal standards requiring that discharges not cause or contribute to low levels of oxygen, which fish need to breath; and unnatural sludge or growth of algae, which harms other forms of life in the water. 

MWRD manages water infrastructure in the nearly 900 square mile region in Cook County. This includes the area’s sewer lines and sewage treatment plants, most notably the three plants that are the subject of the lawsuit – Calumet, North Side, and Stickney.  These plants, the largest in Illinois, are authorized to release over a billion gallons of wastewater every day to Chicago waters, and that wastewater contains large amounts of phosphorus. Excess phosphorus acts as an unnatural fertilizer triggering growth of algae, aquatic plants and bacteria that block sunlight needed by other aquatic life, sucks the oxygen out of the water, and can potentially be toxic. 

Phosphorus is also a major cause of the Dead Zone in the Gulf of Mexico, a huge area in the Gulf where fish and other forms of life cannot survive. Chicago waters, which consist primarily of effluent from the MWRD plants, have been shown to be the largest single contributor of phosphorus to the Dead Zone. As treatment plants around the region address phosphorus, MWRD has fallen behind results achieved by water systems in many Midwestern cities and towns, including Detroit, Milwaukee, and Minneapolis.

MWRD’s water infrastructure also includes dozens of overflow points where untreated sewage combined with storm water pour into the river during rain events that overwhelm the District’s treatment plants.  The sewer system of Chicago, like many older cities, combines waste water with storm water, sending both through the same system of pipes to the sewage treatment plants that are spread around the Chicago area. Because the system is combined, stormwater floods the pipes beyond the capacity of sewage treatment plants, forcing raw sewage and rain water directly to Chicago waters through overflow pipes. 

The release of raw sewage from MWRD’s plants can kill fish, because it takes away the oxygen the fish need to breathe.  The District’s own reports state that the waters receiving its combined sewer overflows violate dissolved oxygen standards a substantial percentage of the time in parts of the Chicago River. Combined sewage and stormwater from the District can also flood basements and force opening of the locks to Lake Michigan.

"We shouldn’t have raw sewage in the Chicago River every time we get a big rainstorm," said Jack Darin, Director of the Illinois Chapter of the Sierra Club. "Upgrading Chicago’s sewers to modern standards will not only give us a healthy river, it will create good jobs when Chicagoans need them the most."

“The millions of dollars MWRD has spent to fight off a cleaner Chicago River could have moved us forward on dealing with the nutrient pollution that fouls waters downstate and in the Gulf of Mexico,” said Glynnis Collins, Executive Director of Prairie Rivers Network, referring to the ongoing hearings before the Illinois Pollution Control Board concerning Illinois EPA’s proposal to improve water quality standards in Chicago area waterways.  “The City, State, and Feds all want to get this rolling. We hope the suit can help force the issue along.” 

The three plaintiffs in this lawsuit have also been battling MWRD in the Pollution Control Board hearings on the question of whether the District should be required to disinfect its sewage effluent, as is done in almost all other major cities across the nation.  

In addition to today’s lawsuit by Chicago River advocates, there are indications that MWRD is in consent decree discussions with the US Department of Justice and USEPA over its outdated sewage infrastructure. This comes a week after USEPA released guidance that “encourages” cities to use green infrastructure to the “maximum extent possible” for stormwater and CSOs. 

In a recent settlement with the USEPA and US Department of Justice, one of the central solutions to similar issues in Cleveland-area waterways is a significant embrace of large-scale green infrastructure projects that use natural systems and materials to hold and clean water in heavy storm events. This green infrastructure can be part of a comprehensive and cost-effective way for cities to address combined sewer overflow problems and improve water quality.  Other cities throughout the Midwest, including Milwaukee, Wisconsin; Aurora, Illinois; and Lenaxa, Kansas, are using green infrastructure to reduce the frequency and severity of combined sewer overflows, while improving neighborhoods and reducing infrastructure costs. Additionally, the work in Cleveland has been estimated to produce 30,000 jobs in northeast Ohio.

Additional Resources:


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