Sweeney Lake

On the LakeGrade rubric, Sweeney Lake pulls an A: clarity at 17.1 ft and phosphorus readings still being added 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.

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. A maximum depth of 18 ft puts Sweeney Lake in the middle of Wisconsin's depth distribution. The lake's 191 acres and partial shoreline records put it in the mid-range bucket — large enough for varied use, small enough that watershed inputs reach the whole basin. Sweeney Lake sits at rank 84 of 140 in Oneida County, in the lower half of the local distribution.

An invasive species record — Chinese Mystery Snail — has been logged at Sweeney Lake; Wisconsin DNR maintains the official infested-waters list. Walleye are documented at Sweeney Lake, one of 5 fish species on record for the lake. A documented public access point at Sweeney 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.