1
BLake Mendota
Dane County, Wisconsin · 4.3 mi from Lake Monona
- +Higher grade (C → B)
- +Lower phosphorus (50.2 vs 93.3 µg/L)
Cleaner Lakes Than Lake Monona
4 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Lake Monona carries a Grade C (Fair) water quality score. Within 30 miles, 4 lakes hold a higher grade. Lake Mendota (Dane County, Grade B, 4.3 mi away) is the closest meaningful upgrade.
2
BLake Wingra
Dane County, Wisconsin · 3.8 mi from Lake Monona
- +Higher grade (C → B)
- +Lower phosphorus (33.8 vs 93.3 µg/L)
3
BLake Waubesa
Dane County, Wisconsin · 4.1 mi from Lake Monona
- +Higher grade (C → B)
- +Lower phosphorus (36.6 vs 93.3 µg/L)
4
BLake Kegonsa
Dane County, Wisconsin · 8.6 mi from Lake Monona
- +Higher grade (C → B)
- +Lower phosphorus (59.5 vs 93.3 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.