Slim Lake

On the LakeGrade rubric, Slim Lake pulls an A: clarity at 15.7 ft and 14 µg/L of phosphorus put it in the top bracket for 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.

Trophically, Slim Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. Slim Lake reaches 42 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. Slim 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. Among the 47 graded lakes in Washburn County, Slim Lake ranks 10 — in the top quartile locally.

Slim Lake has at least one documented invasive species (Chinese Mystery Snail), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. The fishery includes walleye alongside the lake's other 5 documented species — a notable draw for Wisconsin anglers. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.