Grass Lake

On the LakeGrade rubric Grass Lake fails the cutoffs — a TSI of 76 and persistent algal pressure put it in the bottom tier.

A TSI above 70 puts Grass Lake in hypereutrophic territory: visible blooms are common, and clarity rarely climbs even in early summer. 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. Grass Lake ranks 87 of 95 in Hennepin County — at the lower end of the locally monitored distribution.

Grass 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 Grass Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Grass Lake — most use is by shoreline residents and their guests. Ice-out has been recorded 6 times at Grass Lake, with a median around Mar 30. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.