Accidental Sanitary Sewer Release March 11, 2025

An accidental sanitary sewer release occurred on 3-11-25 into Lincoln Creek near 32nd Street and Hampton Avenue in Milwaukee. Workers from MMSD's contractor, Veolia Water Milwaukee, discharged approximately 9,600 gallons of sanitary sewage from a vacuum truck into a storm sewer that the crew mistakenly believed was a sanitary sewer.

MMSD notified the Wisconsin Department of Natural Resources, and reported the incident.  

Steps Taken to Prevent Other Discharges

On March 12, 2025, Veolia crews plugged and cleaned the impacted storm sewer before reopening it for normal operation, and Veolia implemented a mandatory supervisor verification and approval process, requiring staff to confirm and obtain supervisor approval before decanting vacuum trucks. Veolia has additionally scheduled a refresher training for its field crews on proper discharge procedures and verification protocols for the week of March 17, 2025.

MMSD will continue to work with Veolia to determine why this happened and ensure that the proper decanting locations are used in future events.