Perch Lake

Perch Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

A TSI near 50 places Perch Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. At only 13 ft deep, Perch Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. Perch Lake covers 100 acres alongside 3.3 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Within St. Louis County's 215 graded lakes, Perch Lake ranks 113 — below the local median, though not at the bottom.

No invasive species are currently listed at Perch Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at Perch Lake, one of 6 fish species on record for the lake. A documented public access point at Perch Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.