Nearly 10,000 gallons of wastewater mistakenly dumped into Lincoln Creek, Milwaukee River

On March 11, approximately 9,600 gallons of wastewater was accidentally released into Lincoln Creek near North 32nd Street and West Hampton Avenue in Milwaukee.

The incident occurred when workers from Veolia Water Milwaukee, a contractor for the Milwaukee Metropolitan Sewerage District, mistakenly released the wastewater into a storm sewer rather than the sanitary sewer, according to the sewerage district. The discharge can be likened to a sewer overflow, although on a much smaller scale.

The workers were removing water from an underground utility vault, using a vacuum truck when the incident occurred, said Jonathan Hosiak, vice president for Veolia Water Milwaukee. Hosiak explained that there are numerous pipelines and manholes near each other at the location, and the workers picked the wrong one. At that location, the storm sewer funnels water directly into Lincoln Creek, which flows into the Milwaukee River and ultimately Lake Michigan.

The workers identified the mistake after the job was complete, and notified supervisors right away, Hosiak said.

There are no indications of significant environmental impact yet, Hosiak said. On March 12, the company took steps to address the issue by plugging the storm line and cleaning it. Workers confirmed there was no debris along the creek.

To prevent this from happening again, Hosiak said, workers must now obtain supervisor approval to ensure that the manhole leads to the correct line before discharging wastewater into it. He said the situation is rare and not routine, though, as most of the time wastewater is brought back to the plant.

As the permit holder of the pipelines, the sewerage district must submit a report to the Wisconsin Department of Natural Resources. Veolia Water Milwaukee may face fines, though the DNR and sewerage district will investigate before making final conclusions.

Caitlin Looby is a Report for America corps member who writes about the environment and the Great Lakes. Reach her at clooby@gannett.com, follow her on X @caitlooby and learn more about how she approaches her reporting.