Otter Lake

On the LakeGrade scale Otter Lake grades a B, with clarity at 9.0 ft and 18 µg/L of phosphorus placing it above the Minnesota median. Secchi readings are the weakest of the three parameters, suggesting suspended sediment or algal biomass dominates the optical signal.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. The lake's 51 ft maximum depth is in the upper tier for Minnesota — deep enough for cold-water fish to find refuge in summer. Otter Lake is small — 92 acres alongside 2.0 miles of shoreline — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Otter Lake ranks 12 of 55 in Stearns County, putting it in the upper tier of locally monitored lakes.

Zebra mussel presence at Otter Lake means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. Walleye are documented at Otter Lake, one of 13 fish species on record for the lake. The lake lacks a documented public access point, so visitor use is limited. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.