Illinois EPA updates NPDES permit to the city of Chicago

April 16, 2024
The updated permit, effective April 1, 2024, will bring additional oversight of combined sewer overflows.

The Illinois Environmental Protection Agency (Illinois EPA) announced the issuance of a new National Pollutant Discharge Elimination System (NPDES) Permit to the City of Chicago.

The updated permit will bring additional oversight and monitoring of Combined Sewer Overflows (CSOs) to Chicago area waterways. Revisions include substantial enhancements to the permit resulting from stakeholder input.

“This final permit is an outstanding example of collaboration between government entities, environmental advocates, and other members of the public to bring about a robust permit that will further protect the waters and our environment in the greater Chicago area,” said Illinois EPA Director John J. Kim in a press release.

The final permit is said to govern eleven outfalls with discharges to water of the State. These discharges can occur following or after significant rainfall events, which end up in the reservoirs operated by the Metropolitan Water Reclamation District (MWRD) that support the City’s sewer system reach capacity.

The updated permit will include heightened monitoring standards to ensure discharges do not adversely affect waterways around Chicago. The permit also includes enhanced reporting, planning and public engagement requirements, which prioritize the protection of communities of environmental concern.

“While this permit expands on monitoring of combined sewer overflows, it also incorporates a number of other requirements to further address issues raised through the public engagement,” said Kim in the press release.