Prairie Lake

Prairie Lake earns a D — measurements through 2025 show persistent nutrient pressure that limits clarity through the summer. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. Prairie Lake reaches 16 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. Prairie Lake covers 1,408 acres alongside partial shoreline records, large enough that conditions can vary meaningfully between bays. Within the 38 graded lakes of Barron County, Prairie Lake sits at rank 36, near the bottom of the county list.

Prairie 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. The fishery includes walleye alongside the lake's other 5 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.