Teal Lake Deep

The LakeGrade rubric puts Teal Lake Deep at a C: clarity at 3.3 ft, 16 µg/L of phosphorus, and a TSI of 50 signal an intermediate trophic state. The lake's weakest score is on Secchi depth — the water looks more turbid than its phosphorus number alone would predict.

At a TSI of 50, Teal 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. Teal Lake Deep sits at rank 74 of 128 in Cook County, in the lower half of the local distribution.

Zebra mussel presence at Teal Lake Deep means the lake's clarity numbers carry an asterisk — filtered water is not the same as nutrient-poor water. The state fisheries records do not list documented species for Teal Lake Deep, which usually reflects a lack of formal fisheries survey work rather than an empty lake. A documented public access point at Teal Lake Deep makes the lake usable for shore fishing, paddle craft, and trailered boats. Multiple sampling years from Minnesota PCA volunteers and partner agencies back the grade, so the letter should hold steady absent a major watershed shift.