Aerie Lake

Aerie Lake earns an A — water clarity, phosphorus, and chlorophyll-a all rate among the best monitored waters in St. Louis County. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

A TSI value of 25 puts Aerie Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake's maximum depth is not yet documented in state morphometric records — context for its physical structure remains limited. At 146 acres, Aerie Lake fits the Minnesota median for monitored lakes, with 3.4 miles of shoreline. Within St. Louis County's 187 graded waters, Aerie Lake sits at rank 26, near the top of the local distribution.

Aerie Lake has no invasive species recorded in Minnesota state databases as of 2022, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Aerie Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Aerie Lake — most use is by shoreline residents and their guests. Ice-out has been recorded 11 times at Aerie Lake, with a median around Apr 23. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.