Half Moon Lake

Half Moon Lake carries a solid B grade — strong on most parameters, with measurements that hold up well across the summer season. Clarity is the limiting factor — phosphorus is reasonable but suspended particles or algal cells keep water transparency below Wisconsin norms.

A TSI near 46 places Half Moon Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. At only 10 ft deep, Half Moon Lake is shallow — wind keeps the water column mixed and sediment resuspension drives phosphorus levels harder to manage. At 106 acres, Half Moon Lake fits the Wisconsin median for monitored lakes, with partial shoreline records. Within Bayfield County's 52 graded lakes, Half Moon Lake ranks 36 — below the local median, though not at the bottom.

Half Moon Lake has no invasive species recorded in Wisconsin state databases as of 2025, though prevention practices still apply at all access points. The fishery is bass-led, with 3 documented species across the lake's records. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.