1
ATaylor Lake Deep
Cook County, Minnesota · 0.7 mi from Turtle Lake Deep
- +Two grade letters higher (C → A)
- ++335.4 ft water clarity
- +Lower phosphorus (13 vs 22 µg/L)
Cleaner Lakes Than Turtle Lake Deep
2 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Turtle Lake Deep carries a Grade C (Fair) water quality score. Within 30 miles, 2 lakes hold a higher grade. Taylor Lake Deep (Cook County, Grade A, 0.7 mi away) is the closest meaningful upgrade.
2
BNorth Lake Deep
Cook County, Minnesota · 0.5 mi from Turtle Lake Deep
- +Higher grade (C → B)
- +Lower phosphorus (7.7 vs 22 µg/L)
How this list is built
Every lake on LakeQuality has a calculated grade from EPA Water Quality Portal samples — secchi depth, total phosphorus, and chlorophyll-a measured against Metropolitan Council thresholds. To suggest cleaner alternatives, we filter lakes within 30 miles to those with a strictly higher numeric score, then rank by grade improvement with a small proximity tiebreak. Cross-state and limited-data lakes are excluded so the list stays locally relevant.