DNR to lower water levels of Silver Lake to improve water quality

The Minnesota Department of Resources (DNR) announced that it will reduce water levels at Silver Lake in Sibley County to improve water quality and fish and wildlife habitat.

The 697-acre lake had recently been overwhelmed by large populations of common carp, which caused turbid water and impeded aquatic plant growth.

The management plan calls for lowering water levels to about 2 feet to create conditions for a winterkill and reduce common carp populations. This will lower water levels to mimic a drought, acting as a natural “reset,” according to the DNR. Unless future rainfall keeps water levels too high, the drawdown will begin in the current open water season and continue into 2025.

The plan comes after a 2022 survey found the lake was nearly devoid of submerged aquatic vegetation, which plays an important role in maintaining water clarity and fish and wildlife habitat.

According to the DNR, common carp can negatively impact water quality when they uproot plants and disturb phosphorous-rich sediments. This is due to the carp’s feeding habits.

Following the drawdown, the DNR will stock walleye fry in Silver Lake in alternate years and continue to assess the severity of winterkill from either managed drawdowns or natural winterkill events.