Grass Lake

On the LakeGrade rubric, Grass Lake pulls an A: clarity at 28.7 ft and 16 µg/L of phosphorus put it in the top bracket for Wisconsin. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

Trophically, Grass Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. At 52 ft of maximum depth, Grass Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. The lake is compact at 90 acres, with partial shoreline records and little volume to buffer nutrient inputs. Grass Lake ranks 7 of 27 in Shawano County — solidly in the upper half of the local distribution.

Grass Lake is on the Wisconsin infested-waters list for zebra mussels — boaters should follow clean-drain-dry protocols when moving gear to or from the lake. Walleye are documented at Grass Lake, one of 6 fish species on record for the lake. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.