Deer Lake

Deer Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in Iron 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. A maximum depth of 18 ft puts Deer Lake in the middle of Wisconsin's depth distribution. Deer Lake is small — 33 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Among the 34 graded lakes in Iron County, Deer Lake sits at rank 14, above the county median.

Deer Lake has no invasive species recorded in Wisconsin state databases as of 2023, though prevention practices still apply at all access points. The fishery is bass-led, with 2 documented species across the lake's records. 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.