Franklin Lake

Franklin Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI value of 29 puts Franklin Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. A maximum depth of 46 ft puts Franklin Lake in the middle of Wisconsin's depth distribution. Franklin Lake covers 839 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Among the 35 graded lakes in Forest County, Franklin Lake ranks 8 — in the top quartile locally.

Franklin Lake has at least one documented invasive species (Banded Mystery Snail), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. Walleye are documented at Franklin Lake, one of 5 fish species on record for the lake. A documented public access point at Franklin Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.