Lower Vermillion Lake

Lower Vermillion Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. 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.

A TSI value of 37 puts Lower Vermillion Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake's 55 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. Lower Vermillion Lake covers 215 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Lower Vermillion Lake ranks 11 of 38 in Barron County — solidly in the upper half of the local distribution.

Eurasian watermilfoil is established at Lower Vermillion Lake, which can dampen recreational access and pressure the native plant community. Walleye are documented at Lower Vermillion Lake, one of 4 fish species on record for the lake. Public access is available — the lake is on the Wisconsin DNR public-access list. 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.