Fence Lake Deep

On the LakeGrade rubric, Fence Lake Deep pulls an A: clarity at 55.8 ft and phosphorus readings still being added put it in the top bracket for Wisconsin. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI value of 19 puts Fence Lake Deep in the oligotrophic range, where biological productivity stays low and the water column remains clear. At 86 ft of maximum depth, Fence Lake Deep stratifies reliably through the summer — the hypolimnion stays cooler and clearer than the surface layer suggests. Fence Lake Deep covers 3,483 acres alongside partial shoreline records, large enough that conditions can vary meaningfully between bays. Within Vilas County's 202 graded lakes, Fence Lake Deep ranks 118 — below the local median, though not at the bottom.

An invasive species record — Banded Mystery Snail — has been logged at Fence Lake Deep; Wisconsin DNR maintains the official infested-waters list. Walleye are documented at Fence Lake Deep, one of 7 fish species on record for the lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.