Combined Sewer Overflows in the Great Lakes Basin-Illinois
There are 152 NPDES permits which authorize discharges from combined sewer overflows (CSOs) to the Great Lakes Basin. Select the state in the right-side box for the list of CSO permits in the Great Lakes Basin in that state.
There are 42 NPDES permits for CSO discharges in the Great Lakes Basin in Illinois. All 42 of these NPDES CSO permits are in the Chicago metropolitan area and are part of the Tunnel and Reservoir Plan (TARP). The Metropolitan Water Reclamation District of Greater Chicago provides information on CSO discharges from the TARP system and has developed a program where reaches of the Chicagoland waterway map are color coded based on CSO data compiled by staff. The geographical boundaries of the segments are listed in the District's CSO Notification Plan. The Metropolitan Water Reclamation District's website can be queried for CSO Event Synopsis Reports.Exit
| Municipal Operator of CSO | NPDES Permit Number | Water Body Directly Discharged Into |
|---|---|---|
| Brookfield CSO - TARP | ILM580032 | Salt Creek |
| Chicago CSO - TARP | IL0045012 | Chicago CSO - North Shore Channel, North Branch Chicago River, Little Calumet River, Calumet River, Chicago River, South Branch of Chicago River (SBCR), South Fork of SBCR, Chicago Sanitary and Ship Canal, Collateral Channel and Des Plaines River |
| City of Blue Island CSO - TARP | ILM580031 | Cal-Sag Channel |
| City of Calumet City CSO - TARP | ILM580025 | Little Calumet River |
| City of Evanston CSO - TARP | ILM580002 | North Shore Channel |
| City of Harvey - TARP | ILM580020 | Little Calumet River |
| Des Plaines - TARP | ILM580026 | Des Plaines River |
| Dixmoor CSO - TARP | ILM580011 | Little Calumet River |
| Franklin Park CSO - TARP | ILM580029 | Des Plaines River |
| Golf CSO - TARP | IL0072389 | North Branch Chicago River |
| LaGrange Park CSO - TARP | ILM580008 | Salt Creek |
| Lansing CSO - TARP | ILM580027 | Little Calumet River |
| Lincolnwood CSO - TARP | ILM580034 | North Shore Channel |
| MWRDGC | IL0028061, IL0047741, IL0028053, IL0028088 |
Little Calumet River, Weller's Creek, Chicago Sanitary and Ship Canal, North Shore Channel |
| Park Ridge CSO - TARP | ILM580014 | Des Plaines River |
| Phoenix CSO - TARP | IL0072834 | Little Calumet River |
| Posen CSO - TARP | ILM580037 | Cal-Sag Channel |
| Riverside CSO - TARP | ILM580015 | Des Plaines River |
| Skokie CSO - TARP | ILM580036 | North Shore Channel |
| Summit CSO - TARP | ILM580033 | Chicago Sanitary and Ship Canal |
| Village of Arlington Heights CSO - TARP | ILM580006 | Weller's Creek |
| Village of Burnham CSO - TARP | ILM580018 | Grand Calumet River |
| Village of Calumet Park CSO - TARP | ILM580016 | Cal-Sag Channel |
| Village of Dolton CSO - TARP | IL0052426 | Little Calumet River |
| Village of Forest Park CSO - TARP | ILM580019 | Des Plaines River |
| Village of LaGrange CSO - TARP | ILM580009 | Salt Creek |
| Village of Lyons CSO - TARP | ILM580004 | Des Plaines River |
| Village of Maywood CSO - TARP | ILM580022 | Des Plaines River |
| Village of Melrose Park CSO - TARP | ILM580003 | Des Plaines River |
| Village of Morton Grove CSO - TARP | ILM580005 | North Branch Chicago River |
| Village of Niles CSO - TARP | ILM580035 | North Branch Chicago River |
| Village of North Riverside - TARP | ILM580030 | Des Plaines River |
| Village of River Forest CSO - TARP | ILM580024 | Des Plaines River |
| Village of River Grove CSO - TARP | ILM580021 | Des Plaines River |
| Village of Riverdale CSO - TARP | ILM580007 | Little Calumet River |
| Village of Schiller CSO - TARP | ILM580013 | Des Plaines River |
| Village of South Holland CSO - TARP | ILM580010 | Little Calumet River |
| Village of Stickney CSO - TARP | ILM580023 | Chicago Sanitary and Ship Canal |
| Village of Wilmette CSO - TARP | ILM580012 | North Shore Channel |
EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilities.