Gem Lake

The LakeGrade rubric puts Gem Lake at a C: clarity at 6.9 ft, 36 µg/L of phosphorus, and a TSI of 53 signal an intermediate trophic state. 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.

Eutrophic conditions are the baseline here: clarity drops noticeably in late summer, and dissolved oxygen near the bottom can become a concern. 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. Among the 49 graded lakes in Ramsey County, Gem Lake sits at rank 18, above the county median.

Gem Lake has no invasive species recorded in Minnesota state databases as of 2024, though prevention practices still apply at all access points. The state fisheries records do not list documented species for Gem Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Gem Lake — most use is by shoreline residents and their guests. Monitoring depth is thin here: the LakeGrade rubric is applied to a small number of sample years, and the grade will be revised as more data accumulates.