Island Lake

On the LakeGrade scale Island Lake grades a B, with clarity at 8.2 ft and 20 µg/L of phosphorus placing it above the Minnesota median. The three sub-grades — clarity, phosphorus, and chlorophyll-a — track close together, so no single parameter is dragging the average.

A TSI near 47 places Island Lake in the mesotrophic band — moderate productivity, with seasonal swings between clearer spring water and richer late-summer conditions. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. The lake's surface area is not consistently recorded across state datasets — physical context remains partial. Island Lake ranks 111 of 133 in Cass County — at the lower end of the locally monitored distribution.

Island Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Island Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Island Lake — most use is by shoreline residents and their guests. 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.