Spruce Lake

Spruce Lake sits at a C on the grading scale — not impaired, not pristine, with summer measurements that vary year to year. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

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 Carlton County's 33 graded lakes, Spruce Lake ranks 21 — below the local median, though not at the bottom.

No invasive species are currently listed at Spruce Lake — the lake remains off the Minnesota infested-waters roster. The state fisheries records do not list documented species for Spruce Lake, which usually reflects a lack of formal fisheries survey work rather than an empty lake. No formal public access is documented at Spruce Lake — most use is by shoreline residents and their guests. Multiple sampling years from Minnesota PCA volunteers and partner agencies back the grade, so the letter should hold steady absent a major watershed shift.