Hammil Lake

Hammil 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.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. Hammil Lake reaches 47 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 77 acres, Hammil Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Among the 55 graded lakes in Bayfield County, Hammil Lake ranks 5 — in the top quartile locally.

No invasive species are currently listed at Hammil Lake — the lake remains off the Wisconsin infested-waters roster. The fishery includes walleye alongside the lake's other 4 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.