Crystal Lake

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

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. Crystal Lake reaches 43 ft at its deepest point — typical for Wisconsin mid-sized lakes, with seasonal stratification but limited cold-water refuge. Crystal Lake is small — 54 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Among the 140 graded lakes in Oneida County, Crystal Lake ranks 35 — in the top quartile locally.

Crystal Lake has at least one documented invasive species (Rusty Crayfish), so boaters and anglers should observe clean-drain-dry steps when leaving the lake. Bass fishing is part of the appeal: the species list runs to 2, anchored by largemouth and/or smallmouth bass. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.