1
ASt. Marys Lake
St. Louis County, Minnesota · 9.2 mi from Murphy Lake
- +Higher grade (B → A)
- ++11.6 ft water clarity
- +Lower phosphorus (7.5 vs 18 µg/L)
Cleaner Lakes Than Murphy Lake
4 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Murphy Lake carries a Grade B (Good) water quality score. Within 30 miles, 4 lakes hold a higher grade. St. Marys Lake (St. Louis County, Grade A, 9.2 mi away) is the closest meaningful upgrade.
2
AEly Lake
St. Louis County, Minnesota · 10.3 mi from Murphy Lake
- +Higher grade (B → A)
- ++10.8 ft water clarity
- +Lower phosphorus (7 vs 18 µg/L)
3
APleasant Lake
St. Louis County, Minnesota · 6.8 mi from Murphy Lake
- +Higher grade (B → A)
- ++4.8 ft water clarity
- +Lower phosphorus (12.5 vs 18 µg/L)
4
AAnne Lake
St. Louis County, Minnesota · 8.7 mi from Murphy Lake
- +Higher grade (B → A)
- ++9.2 ft water clarity
- +Lower phosphorus (9 vs 18 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.