Big Sand Lake

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

Trophically, Big Sand Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. Big Sand Lake is unusually deep for Wisconsin at 55 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. With 1,434 acres of surface and partial shoreline records, Big Sand Lake is a large water by Wisconsin standards — recreational pressure is spread across a long shoreline. Within Burnett County's 70 graded waters, Big Sand Lake sits at rank 17, near the top of the local distribution.

Big Sand Lake has at least one documented invasive species (Chinese 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.