Patten Lake

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

Mesotrophic conditions dominate at Patten Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. The lake's 52 ft maximum depth is in the upper tier for Wisconsin — deep enough for cold-water fish to find refuge in summer. The lake's 254 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. Patten Lake ranks 12 of 39 in Florence County — solidly in the upper half of the local distribution.

Patten 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 4 documented species — a notable draw for Wisconsin anglers. 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.