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. 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.

At a TSI of 54, Perch Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. Perch Lake reaches 16 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 246 acres, Perch Lake fits the Minnesota median for monitored lakes, with 3.9 miles of shoreline. Within Lincoln County's 5 graded waters, Perch Lake sits at rank 1, near the top of the local distribution.

Perch Lake has no invasive species recorded in Minnesota state databases as of 2021, though prevention practices still apply at all access points. Walleye are documented at Perch Lake, one of 12 fish species on record for the lake. Public access is available — the lake is on the Minnesota PCA public-access list. 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.