City Of Waukesha To Begin Diverting And Returning Lake Michigan Water Under DNR Diversion Approval

MADISON, Wis. – The Wisconsin Department of Natural Resources (DNR) today announced the city of Waukesha plans to start diverting Lake Michigan water for its public water supply this month. The city will return treated wastewater to Lake Michigan via the Root River.

Under the city’s operation plan, water loss to Lake Michigan from the diversion will be minimal, if any. The city has completed the construction of the needed infrastructure to implement the diversion after receiving a diversion approval from the Wisconsin Department of Natural Resources in June 2021.

Due to high radium concentrations contaminating the city’s groundwater wells, the city first applied for a diversion approval with the DNR in 2010. The city is under an amended Department of Justice court order to comply with radium standards by September 2023.

“The city of Waukesha’s project to obtain a new water source solves a long-term public health concern. I’m pleased to have the radium contamination in the city’s water supply eliminated,” said Steve Elmore, DNR Drinking Water and Groundwater Program Director.

The lengthy review process included multiple public hearings and comment periods at the state and Great Lakes regional level, review and approval by the Great Lakes states and provinces and engagement with federally recognized U.S. tribes. In 2016, the city’s application was approved, with conditions by the Great Lakes-St. Lawrence River Basin Water Resources Council, to divert up to 8.2 million gallons per day. Since 2016, the city has obtained the necessary permits and approvals to implement the diversion. The DNR’s 2021 diversion approval was the final step in executing the conditions required by the Great Lakes Compact Council.

“The DNR has worked closely with the city of Waukesha to ensure that their implementation of the diversion meets all the requirements of the Great Lakes Compact Council approval, and the DNR will continue to monitor the implementation of the diversion,” said Adam Freihoefer, DNR Water Use Program Manager.

The city will purchase water from the city of Milwaukee and return treated wastewater to the Root River that flows into Lake Michigan.

Waukesha worked with the DNR to test its new water source and ensure that changing to Lake Michigan water would not cause unexpected water quality problems. The city must monitor water quality in the distribution system following standard Safe Drinking Water Act requirements.

The DNR is regulating the diversion project. The city must report information annually to the DNR, such as the volume diverted, volume returned to Lake Michigan via the Root River, the results of Root River monitoring and the impact of the city’s water conservation and efficiency program. The DNR’s final diversion approval includes all the Great Lakes-St. Lawrence River Basin Water Resources Council conditions.

For more information about the city of Waukesha water diversion project, visit the DNR’s website. Find more information on the city of Waukesha's transition to a Lake Michigan water supply on the Great Water Alliance website.