Little Cosgrove Lake

Little Cosgrove Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year.

Mesotrophic conditions dominate at Little Cosgrove Lake: enough nutrients for a healthy fishery, not so much that algal blooms become a chronic problem. 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. Little Cosgrove Lake ranks 36 of 39 in Florence County — at the lower end of the locally monitored distribution.

No invasive species are currently listed at Little Cosgrove Lake — the lake remains off the Wisconsin infested-waters roster. The state fisheries records do not list documented species for Little Cosgrove Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.