1
DSt. James Lake
Watonwan County, Minnesota · 5 mi from Long Lake
- +Higher overall water quality score
- +Lower phosphorus (51 vs 65.5 µg/L)
Cleaner Lakes Than Long Lake
2 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Long Lake carries a Grade D (Poor) water quality score. Within 30 miles, 2 lakes hold a higher grade. St. James Lake (Watonwan County, Grade D, 5 mi away) is the closest meaningful upgrade.
2
DFedji Lake
Watonwan County, Minnesota · 18.1 mi from Long Lake
- +Higher overall water quality score
- +Lower phosphorus (48 vs 65.5 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.