Oneonta Lake

On the LakeGrade rubric, Oneonta Lake pulls an A: clarity at 24.6 ft and 14 µg/L of phosphorus put it in the top bracket for Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI value of 36 puts Oneonta Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake bottoms out at 24 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 68 acres, Oneonta Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Oneonta Lake ranks 19 of 22 in Marinette County — at the lower end of the locally monitored distribution.

Oneonta Lake has no invasive species recorded in Wisconsin state databases as of 2025, though prevention practices still apply at all access points. The fishery includes walleye alongside the lake's other 4 documented species — a notable draw for Wisconsin anglers. A documented public access point at Oneonta 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.