Crystal Lake

On the scoring rubric Crystal Lake grades a D: clarity at 2.5 ft and 47 µg/L of phosphorus keep it in the lower bracket for Oneida County. Secchi readings are the weakest of the three parameters, suggesting suspended sediment or algal biomass dominates the optical signal.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. At only 9 ft deep, Crystal Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. The lake's 116 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. Within the 134 graded lakes of Oneida County, Crystal Lake sits at rank 109, near the bottom of the county list.

An invasive species record — Banded Mystery Snail — has been logged at Crystal Lake; Wisconsin DNR maintains the official infested-waters list. The fishery includes walleye alongside the lake's other 5 documented species — a notable draw for Wisconsin anglers. Public access is available — the lake is on the Wisconsin DNR public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.