Lost Lake

Lost Lake sits at the top of the Minnesota PCA grading rubric with an A, a mark reached by the cleanest lakes in Minnesota. Sub-grades cluster within a single letter of each other, which usually means the lake is in stable trophic balance rather than fighting one specific stressor.

A TSI value of 32 puts Lost Lake in the oligotrophic range, where biological productivity stays low and the water column remains clear. The lake bottoms out at 44 ft — a moderate depth that supports a warm-water fishery without the year-round cold refuge a deeper basin provides. At 124 acres, Lost Lake fits the Minnesota median for monitored lakes, with 3.4 miles of shoreline. Within St. Louis County's 187 graded waters, Lost Lake sits at rank 15, near the top of the local distribution.

Lost Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. The fishery is panfish-dominated — bluegill, crappie, and sunfish among the 8 species documented for the lake. A documented public access point at Lost Lake makes the lake usable for shore fishing, paddle craft, and trailered boats. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.