South Farm Lake

On the scoring rubric South Farm Lake grades a D: clarity at 5.0 ft and phosphorus readings still being added keep it in the lower bracket for Lake County. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

At a TSI of 54, South Farm Lake reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. A maximum depth of 31 ft puts South Farm Lake in the middle of Minnesota's depth distribution. At 564 acres, South Farm Lake fits the Minnesota median for monitored lakes, with 10.8 miles of shoreline. South Farm Lake ranks 118 of 142 in Lake County — at the lower end of the locally monitored distribution.

No invasive species are currently listed at South Farm Lake — the lake remains off the Minnesota infested-waters roster. Walleye are documented at South Farm Lake, one of 11 fish species on record for the lake. The lake lacks a documented public access point, so visitor use is limited. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.