Carrol Lake

Carrol Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI near 47 places Carrol Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. The lake bottoms out at 27 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 330 acres, Carrol Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Within the 140 graded lakes of Oneida County, Carrol Lake sits at rank 130, near the bottom of the county list.

Eurasian watermilfoil has been documented at Carrol Lake, requiring shoreline management to keep dense mats from crowding native vegetation. Walleye are documented at Carrol Lake, one of 5 fish species on record for the lake. Public access is available — the lake is on the Wisconsin DNR public-access list. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.