Circle Lily Lake

On the LakeGrade rubric, Circle Lily Lake pulls an A: clarity at 18.9 ft and 15 µg/L of phosphorus put it in the top bracket for Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

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. A maximum depth of 35 ft puts Circle Lily Lake in the middle of Wisconsin's depth distribution. The lake's 218 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. Among the 202 graded lakes in Vilas County, Circle Lily Lake ranks 48 — in the top quartile locally.

Circle Lily Lake has at least one documented invasive species (Rusty Crayfish), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. Walleye are documented at Circle Lily Lake, one of 6 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.