Hasbrook Lake

On the LakeGrade rubric, Hasbrook Lake pulls an A: clarity at 21.0 ft and 10 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.

A TSI value of 36 puts Hasbrook Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. Hasbrook Lake is unusually deep for Wisconsin at 50 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. Hasbrook Lake covers 307 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 134 graded lakes in Oneida County, Hasbrook Lake ranks 10 — in the top quartile locally.

Eurasian watermilfoil is established at Hasbrook Lake, which can dampen recreational access and pressure the native plant community. Walleye are documented at Hasbrook Lake, one of 5 fish species on record for the lake. A documented public access point at Hasbrook Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. 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.