Detroit Lakes Wastewater Treatment Facility Planning, Design and Construction Administration

Challenge

The City of Detroit Lakes in northwest Minnesota had a 60-year-old wastewater treatment facility that was tasked with treating 2.2 million gallons per day of wastewater to support a growing population. A study by the Minnesota Pollution Control Agency (MPCA) and Pelican River Watershed District (PRWD) revealed that phosphorus levels from various sources were affecting Lake St. Claire. MPCA directed the City to reduce the phosphorous content of the wastewater effluent entering the lake by 94%.

Solution

After evaluating 12 alternatives, Detroit Lakes Public Utilities Commission and SEH determined that leaving the plant and discharge in place was the best long-range choice when paired with innovative technologies to meet system demands and reduce nutrient loads. The $30 million improved treatment system includes a membrane biological reactor (MBR), a process that uses membranes to physically separate solids, replacing traditional clarification and filtration processes.

By embracing innovation, the new wastewater treatment plant meets one of the most stringent phosphorus limits in Minnesota. In fact, the facility’s performance has surpassed expectations, with lower operational costs than anticipated. This is now one of the most innovative wastewater treatment facilities in Minnesota, serving as a model for communities faced with similar challenges.

Awards

• 2022 Engineering Excellence Grand Award | American Council of Engineering Companies, Minnesota Chapter (ACEC-MN)