1
AMaple Lake
Douglas County, Minnesota · 6.2 mi from Ann Lake
- +Two grade letters higher (D → A)
- ++5.3 ft water clarity
- +Lower phosphorus (15 vs 496.5 µg/L)
Cleaner Lakes Than Ann Lake
5 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Ann Lake carries a Grade D (Poor) water quality score. Within 30 miles, 5 lakes hold a higher grade. Maple Lake (Douglas County, Grade A, 6.2 mi away) is the closest meaningful upgrade.
2
BMinnewaska Lake
Pope County, Minnesota · 5.1 mi from Ann Lake
- +Two grade letters higher (D → B)
- ++2.8 ft water clarity
- +Lower phosphorus (23.5 vs 496.5 µg/L)
3
BScandinavian Lake
Pope County, Minnesota · 6.8 mi from Ann Lake
- +Two grade letters higher (D → B)
- +Lower phosphorus (17 vs 496.5 µg/L)
4
CReno Lake
Pope County, Minnesota · 3.6 mi from Ann Lake
- +Higher grade (D → C)
- +Lower phosphorus (33 vs 496.5 µg/L)
5
CPelican Lake
Pope County, Minnesota · 3.7 mi from Ann Lake
- +Higher grade (D → C)
- +Lower phosphorus (49 vs 496.5 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.