Perch Lake

Perch Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Oneida County. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

A TSI value of 32 puts Perch Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. Perch Lake is unusually deep for Wisconsin at 56 ft, which buffers the lake against summer warming and helps the deep water stay oxygenated. The lake is compact at 34 acres, with partial shoreline records and little volume to buffer nutrient inputs. Among the 140 graded lakes in Oneida County, Perch Lake sits at rank 39, above the county median.

Perch 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. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.