Lost Lake

On the LakeGrade rubric, Lost Lake pulls an A: clarity at 15.0 ft and 8 µg/L of phosphorus put it in the top bracket for 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.

Trophically, Lost Lake reads as oligotrophic — nutrient-poor, clear, and ecologically more sensitive to disturbance than richer lakes. A maximum depth of 26 ft puts Lost Lake in the middle of Minnesota's depth distribution. At 69 acres, Lost Lake sits below the Minnesota median: a small water where shoreline activity has an outsized effect on water quality. Within Cass County's 133 graded waters, Lost Lake sits at rank 25, near the top of the local distribution.

No invasive species are currently listed at Lost Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Lost Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Lost Lake — most use is by shoreline residents and their guests. Ice-out has been recorded 12 times at Lost Lake, with a median around Apr 15. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.