Ahsub Lake

On the LakeGrade rubric, Ahsub Lake pulls an A: clarity at 18.0 ft and phosphorus readings still being added put it in the top bracket for Minnesota. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI value of 35 puts Ahsub Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. At 78 ft of maximum depth, Ahsub Lake stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. The lake is compact at 60 acres, with 2.5 miles of shoreline and little volume to buffer nutrient inputs. Within Lake County's 142 graded waters, Ahsub Lake sits at rank 9, near the top of the local distribution.

No invasive species are currently listed at Ahsub Lake — the lake remains off the Minnesota infested-waters roster. Bass fishing is part of the appeal: the species list runs to 6, anchored by largemouth and/or smallmouth bass. No formal public access is documented at Ahsub Lake — most use is by shoreline residents and their guests. 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.