Spruce Lake

The LakeGrade rubric puts Spruce Lake at a C: clarity at 8.2 ft, phosphorus readings still being added, and a TSI of 47 signal an intermediate trophic state. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. The lake bottoms out at 15 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 10 acres, Spruce Lake sits below the Wisconsin median: a small water where shoreline activity has an outsized effect on water quality. Within the 140 graded lakes of Oneida County, Spruce Lake sits at rank 132, near the bottom of the county list.

No invasive species are currently listed at Spruce Lake — the lake remains off the Wisconsin infested-waters roster. 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. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.