Mirror Lake

Mirror Lake earns a C — middle-of-the-pack water quality, with one or two parameters dragging the average down from a stronger grade.

The lake sits in the mesotrophic zone — the band where most well-managed Wisconsin lakes fall. At only 13 ft deep, Mirror Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. Mirror Lake is small — 9 acres alongside partial shoreline records — which makes it sensitive to even modest changes in watershed runoff or recreational pressure. Mirror Lake sits at rank 29 of 39 in Florence County, in the lower half of the local distribution.

Mirror Lake has no invasive species recorded in Wisconsin state databases as of 2023, though prevention practices still apply at all access points. 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.