Neligan Lake

Neligan 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.

The lake's low TSI puts it in oligotrophic territory — the cleanest of the four trophic classes, but also the most vulnerable to nutrient-driven shifts. The lake bottoms out at 23 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 48 acres, Neligan Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within Oconto County's 66 graded waters, Neligan Lake sits at rank 3, near the top of the local distribution.

No invasive species are currently listed at Neligan Lake — the lake remains off the Wisconsin infested-waters roster. The fishery is bass-led, with 3 documented species across the lake's records. A documented public access point at Neligan 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.