South Twin Lake

South Twin Lake sits at the top of the Minnesota PCA grading rubric with an A, a mark reached by the cleanest lakes in Minnesota. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

Trophically, South Twin Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. South Twin Lake reaches 45 ft at its deepest point — typical for Minnesota mid-sized lakes, with seasonal stratification but limited cold-water refuge. South Twin Lake covers 222 acres alongside 3.1 miles of shoreline — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. South Twin Lake ranks 23 of 86 in Beltrami County — solidly in the upper half of the local distribution.

South Twin Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. Walleye are documented at South Twin Lake, one of 11 fish species on record for the lake. A documented public access point at South Twin Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.