Horsehead Lake

Horsehead Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. Of the three parameters, phosphorus is the worst — at 30 µg/L of phosphorus, it keeps the lake susceptible to algal blooms in warm years.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. Horsehead Lake is a shallow lake at 11 ft maximum depth, which means it warms quickly, mixes constantly, and amplifies nutrient inputs. The lake's 377 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. Horsehead Lake sits at rank 105 of 140 in Oneida County, in the lower half of the local distribution.

Eurasian watermilfoil has been documented at Horsehead Lake, requiring shoreline management to keep dense mats from crowding native vegetation. The fishery is bass-led, with 3 documented species across the lake's records. A documented public access point at Horsehead 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.