Swamp Lake Deep

The LakeGrade rubric puts Swamp Lake Deep at a C: clarity at 1.7 ft, 27 µg/L of phosphorus, and a TSI of 58 signal an intermediate trophic state. Secchi readings are the weakest of the three parameters, suggesting suspended sediment or algal biomass dominates the optical signal.

At a TSI of 58, Swamp Lake Deep reads as eutrophic — nutrient-rich enough that summer algal growth and reduced clarity are expected, not unusual. 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 Cook County's 128 graded lakes, Swamp Lake Deep ranks 91 — below the local median, though not at the bottom.

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