Loon Lake

On the LakeGrade rubric, Loon Lake pulls an A: clarity at 29.5 ft and 15 µg/L of phosphorus put it in the top bracket for 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. The lake bottoms out at 28 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. The lake's 191 acres and partial shoreline records put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Within Burnett County's 70 graded waters, Loon Lake sits at rank 6, near the top of the local distribution.

Loon 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. Bass fishing is part of the appeal: the species list runs to 3, anchored by largemouth and/or smallmouth bass. 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.