Stone Lake

The LakeGrade rubric puts Stone Lake at a C: clarity readings still being added, 31 µg/L of phosphorus, and a TSI of 53 signal an intermediate trophic state. Clarity, phosphorus, and chlorophyll-a all rate similarly, so there is no obvious single lever to pull on watershed management.

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. Within St. Louis County's 187 graded lakes, Stone Lake ranks 129 — below the local median, though not at the bottom.

No invasive species are currently listed at Stone Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Stone Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. Public access is available — the lake is on the Minnesota PCA public-access list. The grade is based on limited monitoring — fewer than three independent measurement years contribute, so future updates may shift the letter.