Sarah Lake

Sarah Lake comes in at a B on the grading rubric — a respectable showing for a Minnesota lake of its size and depth. 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 50, Sarah Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. Sarah Lake reaches 27 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. Sarah Lake covers 366 acres alongside 5.3 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Sarah Lake ranks 6 of 20 in Polk County — solidly in the upper half of the local distribution.

No invasive species are currently listed at Sarah Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at Sarah Lake, one of 10 fish species on record for the lake. Public access is available — the lake is on the Minnesota PCA public-access list. Ice-out has been recorded 13 times at Sarah Lake, with a median around Apr 16. 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.