Clear Lake

Clear Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Polk County. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

Trophically, Clear Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. Clear Lake reaches 26 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. At 30 acres, Clear Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within Polk County's 77 graded waters, Clear Lake sits at rank 6, near the top of the local distribution.

An invasive species record — Chinese Mystery Snail — has been logged at Clear Lake; Wisconsin DNR maintains the official infested-waters list. The fishery includes walleye alongside the lake's other 4 documented species — a notable draw for Wisconsin anglers. A documented public access point at Clear 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.