Catfish Lake

Catfish Lake earns a D — measurements through 2026 show persistent nutrient pressure that limits clarity through the summer. 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 in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. A maximum depth of 30 ft puts Catfish Lake in the middle of Wisconsin's depth distribution. With 1,012 acres of surface and partial shoreline records, Catfish Lake is a large water by Wisconsin standards — recreational pressure is spread across a long shoreline. Catfish Lake ranks 185 of 191 in Vilas County — at the lower end of the locally monitored distribution.

Eurasian watermilfoil is established at Catfish Lake, which can dampen recreational access and pressure the native plant community. Walleye are documented at Catfish Lake, one of 6 fish species on record for the lake. A documented public access point at Catfish Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.