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National Pollutant Discharge Elimination System (NPDES)

Combined Sewer Overflows in the Great Lakes Basin-Wisconsin

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 two NPDES permits for CSO discharges in the Great Lakes Basin in Wisconsin. The table below provides information about those permittees and links to their CSO website and Annual Notice describing the CSO discharges that occurred in 2018.

Map of CSO communities in Wisconsin that drain to the Great Lakes Basin

The following links exit the site Exit

Municipal Operator of CSO NPDES Permit Number Great Lake Discharged To Water Body Directly Discharged Into Website Annual CSO Notice
Milwaukee WI0036820 Lake Michigan Lake Michigan Milwaukee website Milwaukee annual notice
(91 pp, 10.9 MB, About PDF)
Superior WI0025593 Lake Superior Lake Superior Superior website Superior annual notice
(26 pp, 6.5 MB, About PDF)

EPA’s Enforcement and Compliance History Online (ECHO) database has additional information on NPDES discharges, including CSO discharges for some facilities.

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