Bullhead Lake

Bullhead Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade. High phosphorus is the leading drag on the score — likely from upland agriculture, lawn runoff, or in-lake sediment release.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. Bullhead Lake reaches 40 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 70 acres, Bullhead Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within the 18 graded lakes of Manitowoc County, Bullhead Lake sits at rank 16, near the bottom of the county list.

Bullhead Lake carries an invasive watermilfoil record — boat-launch decontamination and shoreline care matter more here than at uninfested lakes. The fishery includes walleye alongside the lake's other 4 documented species — a notable draw for Wisconsin anglers. 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.