1
AForest Lake
Fond du Lac County, Wisconsin · 0.9 mi from Mauthe Lake
- +Higher grade (B → A)
- ++26.5 ft water clarity
- +Lower phosphorus (14.2 vs 54 µg/L)
Cleaner Lakes Than Mauthe Lake
5 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Mauthe Lake carries a Grade B (Good) water quality score. Within 30 miles, 5 lakes hold a higher grade. Forest Lake (Fond du Lac County, Grade A, 0.9 mi away) is the closest meaningful upgrade.
2
AKettle Moraine Lake
Fond du Lac County, Wisconsin · 3.8 mi from Mauthe Lake
- +Higher grade (B → A)
- ++16.7 ft water clarity
- +Lower phosphorus (16.2 vs 54 µg/L)
3
ALong Lake
Fond du Lac County, Wisconsin · 4.8 mi from Mauthe Lake
- +Higher grade (B → A)
- ++13.4 ft water clarity
- +Lower phosphorus (19.3 vs 54 µg/L)
4
ALake Ellen
Sheboygan County, Wisconsin · 9 mi from Mauthe Lake
- +Higher grade (B → A)
- ++10.1 ft water clarity
- +Lower phosphorus (12.4 vs 54 µg/L)
5
AAuburn Lake
Fond du Lac County, Wisconsin · 1.2 mi from Mauthe Lake
- +Higher grade (B → A)
- ++5.2 ft water clarity
- +Lower phosphorus (24.4 vs 54 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.