Shannon Lake

Shannon Lake sits at the top of the Wisconsin DNR grading rubric with an A, a mark reached by the cleanest lakes in Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

Trophically, Shannon Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. A maximum depth of 30 ft puts Shannon Lake in the middle of Wisconsin's depth distribution. Shannon Lake is small — 35 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Within Vilas County's 202 graded lakes, Shannon Lake ranks 122 — below the local median, though not at the bottom.

Shannon Lake has no invasive species recorded in Wisconsin state databases as of 2022, though prevention practices still apply at all access points. 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. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.