Drawdown will address issues with fish and degraded habitat
The Minnesota Department of Natural Resources is conducting a drawdown on Lake Maria in Murray County, located southwest of Garvin. The temporary lowering of water levels on the 442-acre shallow lake is taking place to improve wildlife habitat and water quality.
Lake Maria is a designated wildlife lake, which allows DNR managers to help mitigate factors that affect water and habitat quality with tools that include temporary drawdowns. More information about designated wildlife lakes is available on the Minnesota DNR website.
It has been three years since the last drawdown on Lake Maria and habitat conditions have deteriorated in the basin. The 2022 drawdown improved clarity from 1.35 feet to 1.61 feet.
Average water clarity during the 2024 wildlife lake survey was less than 1.5 feet, which is below the management goal of greater than 2.3 feet, and emergent aquatic vegetation has significantly declined. Common carp, black bullheads, and minnows also are abundant in Lake Maria. All these factors indicate declining in-lake habitat conditions.
“Lake Maria is an important lake for many migrating birds and breeding waterfowl,” said Maggie Gross, DNR shallow lakes specialist. “However, the presence of undesirable fish species is negatively affecting water clarity and aquatic vegetation in the lake, which in turn is reducing the amount of quality habitat and food resources for these birds.”
Drawdowns act as a natural “reset” to shallow lake ecosystems by mimicking drought conditions. Low water levels allow new aquatic vegetation to germinate and firm up the lake bottom. Drawdowns also help reduce populations of undesirable fish, which degrade water quality through their feeding behavior.
Plans call for using pumps to lower water levels by about 2.75 feet from a maximum depth of 3.3 feet. Lake Maria will remain in drawdown through the spring of 2026, depending on weather conditions. There is a possibility the drawdown could be extended into the summer of 2026 if there is not enough new aquatic vegetation growth in the lake.
Anyone with questions about the Lake Maria drawdown or shallow lake management can contact Maggie Gross, Windom shallow lakes specialist, [email protected] or 507-832-6016. Questions about Lake Maria also can be directed to Bill Schuna, Slayton-Talcot area wildlife manager, [email protected] or 507-873-5650.