1
ASpectacle Lake
Isanti County, Minnesota · 1.8 mi from Green Lake
- +Two grade letters higher (C → A)
- ++8.7 ft water clarity
- +Lower phosphorus (11 vs 44 µg/L)
Cleaner Lakes Than Green Lake
3 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Green Lake carries a Grade C (Fair) water quality score. Within 30 miles, 3 lakes hold a higher grade. Spectacle Lake (Isanti County, Grade A, 1.8 mi away) is the closest meaningful upgrade.
2
ASandy Lake
Sherburne County, Minnesota · 7.1 mi from Green Lake
- +Two grade letters higher (C → A)
- ++9 ft water clarity
- +Lower phosphorus (12.5 vs 44 µg/L)
3
CBlue Lake
Isanti County, Minnesota · 6.9 mi from Green Lake
- +Higher overall water quality score
- ++3.8 ft water clarity
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.