Crooked Lake

Crooked Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Oconto County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI value of 33 puts Crooked Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake bottoms out at 37 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. Crooked Lake covers 162 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Crooked Lake ranks 32 of 66 in Oconto County — solidly in the upper half of the local distribution.

Zebra mussels have been documented at Crooked Lake, which alters the filter-feeding balance and can paradoxically increase water clarity while disrupting the food web. The fishery is bass-led, with 3 documented species across the lake's records. 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.