MPCA Removes Wirth Lake From State’s Impaired Waters List
The Minnesota Pollution Control Agency (MPCA) has removed Wirth Lake in Golden Valley from the state’s Impaired Waters List and has submitted the action, termed “delisting,” to the United States Environmental Protection Agency for final approval. Wirth Lake has been on the list since 2002 due to excess nutrients, specifically phosphorous.
Wirth Lake is on Minneapolis Park and Recreation Board property and is in the Bassett Creek watershed. The lake’s water quality improved significantly over the years due to projects identified and constructed through the joint efforts of the Bassett Creek Watershed Management Commission (BCWMC), City of Golden Valley, City of Minneapolis, Minneapolis Park and Recreation Board, and MPCA as well as with assistance from the Minnesota Board of Water and Soil Resources through its Legacy Funds grant program. For example, average summer water transparency increased from 3.8 feet in 1992 to a consistent 8.3-10.5 feet since 2008.
Among the projects contributing to Wirth Lake’s reduction in phosphorous were the water quality pond improvements constructed in 2005-2006 just west of Wirth Lake. The pond was a cooperative project between the BCWMC and the Minneapolis Park and Recreation Board. A more recent project involved the 2012 modification of the Wirth Lake outlet, a collaborative effort between the BCWMC and the City of Golden Valley. The modified outlet reduced phosphorous loading into Wirth Lake by preventing backflow from Bassett Creek into Wirth Lake during flood events.
According to Bassett Creek Watershed Management Commission Chair Jim de Lambert, the delisting of Wirth Lake from the Impaired Waters List “is a testament to the focus and resolve of everyone involved, from residents providing comments and attending public hearings to the agencies, cities, and organizations involved in the monitoring, planning, and implementing of projects.”
The Bassett Creek Watershed Management Commission (BCWMC) is a Joint Powers water management organization comprising nine municipalities: Crystal, Golden Valley, New Hope, Medicine Lake, Minneapolis, Minnetonka, Plymouth, Robbinsdale, and St Louis Park. Originating from the Bassett Creek Flood Control Commission formed in 1969, the BCWMC was established in 1982. The BCWMC’s Watershed Management Plan sets the vision and guidelines for the management of surface water in the Bassett Creek watershed. The watershed is approximately 40 square miles, divided into four subwatersheds.