Fourmile Lake

Fourmile Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. 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.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. A maximum depth of 29 ft puts Fourmile Lake in the middle of Wisconsin's depth distribution. Fourmile Lake covers 210 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Fourmile Lake ranks 120 of 140 in Oneida County — at the lower end of the locally monitored distribution.

Fourmile Lake has at least one documented invasive species (Rusty Crayfish), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. The fishery includes walleye alongside the lake's other 6 documented species — a notable draw for Wisconsin anglers. 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.