Lake levels impacted by persistent drought

North-central Minnesota experiencing “storage drought”

With lower-than-normal rainfall and higher-than-normal temperatures in the last few weeks, persistent drought and lower lake levels have become common across a large portion of the state.

Much of north-central Minnesota is experiencing storage drought. In years of significant drought, long-term water storage is depleted in lakes, soil and groundwater to a degree that typically takes years to reverse.

“A few heavy rain events aren’t enough to pull an area out of storage drought,” Minnesota Department of Natural Resources State Climatologist Luigi Romolo said. “Over the past four years, north-central Minnesota has received 12 to 16 inches below normal precipitation. So, it would take months of precipitation far above normal amounts to bring lake levels and soil moisture back to typical levels.”

Although it can be frustrating to those who recreate or live on lakes, varying water levels are not only natural and normal, they’re essential to many important plant and animal species. Low water consolidates lake bottom sediment and can stimulate aquatic plant growth, both of which are helpful to the aquatic ecosystem. For example, some aquatic plants that can’t germinate underwater provide habitat for fish and insects and help reduce shoreline erosion. More information is available in a DNR video about lake ecosystems (youtu.be/MMnf_yVHOWc).

“Patience is important when these cycles affect human enjoyment of a lake,” DNR Conservation Assistance and Regulation Section Manager Randall Doneen said. “While many are eager to see lakes at levels more conducive to boating and other uses, people should refrain from activities such as manipulating lake level outlets or undertaking enhanced shoreline alterations during temporary low-level conditions.”

To support a healthy lake, check with the local area hydrologist (mndnr.gov/waters/area-hydrologist-contact-information.html) prior to undertaking any construction activities within or near low water. The DNR regulates activities that occur below the ordinary high water level (mndnr.gov/waters/surfacewater_section/hydrographics/ohw.html). In areas currently experiencing low water, the ordinary high water level could be considerably farther up the banks than the current water level.

Lake levels and soil moisture are influenced by not only precipitation but also snowpack, groundwater levels, watershed conditions and evaporation. Storage drought is often compounded by increased water use, including irrigation for crops, lawns and athletic fields.

“Times of drought remind us of the importance of water conservation. Water use increases as conditions become drier, and that can impact water supplies,” Doneen said. “We encourage all water users to be mindful of how much water they’re using, not just during drought but on an ongoing basis.”

Minnesotans are encouraged to learn how much water they are using (mndnr.gov/waters/watermgmt_section/appropriations/water-conservation-residents.html) compared to the average American home and identify ways to reduce water use now and in the future. Reducing use today saves water for the future.

A map of Minnesota watersheds, a link to the U.S. Drought Monitor Map and more information about drought in Minnesota is available on the DNR website (mndnr.gov/climate/drought/index.html). The website includes a link where anyone can sign up to receive drought-related information and notifications.