Fourtown Lake

The LakeGrade rubric puts Fourtown Lake at a C: clarity at 7.0 ft, phosphorus readings still being added, and a TSI of 49 signal an intermediate trophic state. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The lake sits in the mesotrophic zone — the band where most well-managed Minnesota lakes fall. A maximum depth of 27 ft puts Fourtown Lake in the middle of Minnesota's depth distribution. At 323 acres, Fourtown Lake fits the Minnesota median for monitored lakes, with 7.3 miles of shoreline. Fourtown Lake ranks 124 of 159 in Lake County — at the lower end of the locally monitored distribution.

No invasive species are currently listed at Fourtown Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Fourtown Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Fourtown Lake — most use is by shoreline residents and their guests. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.