The Minnesota Department of Natural Resources has established a protective elevation for White Bear Lake, located in Ramsey and Washington counties. The protective elevation is 922.0 feet above mean sea level. The current level of White Bear Lake is 922.7 feet. A protective elevation is a regulatory measure used to trigger changes in water appropriations to prevent undue harm to a lake.
“The protective elevation is intended to protect and maintain fish and wildlife habitat and support recreational uses of the lake,” according to DNR Assistant Commissioner Barb Naramore. “However, people should understand that a protective elevation is not a fixed level that is maintained or minimum level that is guaranteed. Lake levels are driven by several factors and fluctuate. Indeed, White Bear Lake’s long term ecological health depends upon variation in water level within the lake’s historic range.”
In establishing the protective elevation for the lake, the DNR has considered multiple factors, including:
Historic record of lake water levels.
Aquatic vegetation important for fish and wildlife habitat.
Water quality and clarity.
Recreational uses, including boat access, navigation, and swimming beaches.
Area and slope of the lakebed.
When water levels are low on White Bear Lake, there are impacts to some recreational uses. The DNR did not find evidence that periods of low water harm the lake’s biology or ecology. In fact, the DNR found that periodic low water levels renew aquatic vegetation, providing important habitat for fish and wildlife. Robust native aquatic vegetation also protects shorelines from erosion due to waves and ice-heaving.
Protective elevations are generally set for lakes that are subject to direct surface water withdrawals. This is the first time the DNR has set a protective elevation for a Minnesota lake to assist in managing the potential impacts of nearby groundwater appropriations. Establishing the protective elevation is the first step in a multi-part process. The DNR will consider how to apply the protective elevation to existing and new groundwater appropriation permits in the area. The first step in this phase is evaluating the impact of groundwater use on White Bear Lake water levels.
For those appropriations demonstrated to have a material effect on lake levels, the DNR will then modify the permits to incorporate the protective elevation. Permit modifications might include implementing use restrictions to help support the protective elevation. Such use restrictions would focus reduction on nonessential use such as lawn watering. Essential residential water use, such as drinking, cooking, and cleaning would not be restricted.
“This is the first protective elevation established by the DNR to manage groundwater use rather than direct surface water appropriations, so we will be exploring how best to apply it,” Naramore said.
The DNR is setting the protective elevation in connection with the 2014 settlement agreement among parties to litigation concerning water levels on White Bear Lake. The plaintiffs claim permitted groundwater withdrawals are damaging White Bear Lake. The case is scheduled for trial in March 2017.
In announcing its decision, the DNR emphasized that a protective elevation is not the same as an ordinary high water level (OHW). The OHW is a regulatory term and is defined as the elevation where vegetation transitions from primarily aquatic to primarily upland. It is important to understand that the OHW is not an average water level and is certainly not a goal for water levels. Water levels may occasionally rise above the OHW for relatively brief periods of time, but are below the OHW the large majority of the time. The OHW for White Bear Lake is 924.9 feet above mean sea level. The long-term average water level on White Bear Lake is 923.1 feet and the elevation at the current lake outlet is 924.3 feet.
More information about lake levels and protected elevation is available at mndnr.gov/gwmp/wbl.