Hat Rapids Flowage Lake

On the scoring rubric Hat Rapids Flowage Lake grades a D: clarity at 3.5 ft and phosphorus readings still being added keep it in the lower bracket for Oneida County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI in the eutrophic range signals a lake doing what nutrient-loaded waters do — supporting an active algal community at the cost of clear water. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. Hat Rapids Flowage Lake covers 295 acres alongside partial shoreline records — a mid-sized water that supports a working fishery without being so large that conditions diverge between basins. Hat Rapids Flowage Lake ranks 106 of 134 in Oneida County — at the lower end of the locally monitored distribution.

Hat Rapids Flowage Lake has at least one documented invasive species (Chinese Mystery Snail), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. The state fisheries records do not list documented species for Hat Rapids Flowage Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. 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.