1
BRound Lake
Anoka County, Minnesota · 3.5 mi from Grass Lake
- +Higher grade (C → B)
- ++4.3 ft water clarity
Cleaner Lakes Than Grass Lake
2 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Grass Lake carries a Grade C (Fair) water quality score. Within 30 miles, 2 lakes hold a higher grade. Round Lake (Anoka County, Grade B, 3.5 mi away) is the closest meaningful upgrade.
2
BCrooked Lake
Anoka County, Minnesota · 4.5 mi from Grass Lake
- +Higher grade (C → B)
- ++3.5 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.