Big Trade Lake

On the LakeGrade rubric, Big Trade Lake pulls an A: clarity at 16.4 ft and 29 µg/L of phosphorus put it in the top bracket for Wisconsin. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. Big Trade Lake reaches 39 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. The lake's 327 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. Within Burnett County's 70 graded lakes, Big Trade Lake ranks 52 — below the local median, though not at the bottom.

Eurasian watermilfoil is established at Big Trade Lake, which can dampen recreational access and pressure the native plant community. Walleye are documented at Big Trade Lake, one of 5 fish species on record for the lake. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.