Dunn Lake

Dunn Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. 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 22 puts Dunn Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake bottoms out at 39 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 181 acres, Dunn Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Dunn Lake sits at rank 32 of 48 in Washburn County, in the lower half of the local distribution.

An invasive species record — Chinese Mystery Snail — has been logged at Dunn Lake; Wisconsin DNR maintains the official infested-waters list. Walleye are documented at Dunn Lake, one of 4 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.