1
BWeatherby Lake
Platte County, Wisconsin · 17.5 mi from Smithville Lake
- +Two grade letters higher (D → B)
- ++4.2 ft water clarity
- +Lower phosphorus (16 vs 48.8 µg/L)
Cleaner Lakes Than Smithville Lake
3 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Smithville Lake carries a Grade D (Poor) water quality score. Within 30 miles, 3 lakes hold a higher grade. Weatherby Lake (Platte County, Grade B, 17.5 mi away) is the closest meaningful upgrade.
2
CWaukomis Lake
Platte County, Wisconsin · 16 mi from Smithville Lake
- +Higher grade (D → C)
- ++2.7 ft water clarity
- +Lower phosphorus (26 vs 48.8 µg/L)
3
DWatkins Mill Lake
Clay County, Wisconsin · 15.1 mi from Smithville Lake
- +Higher overall water quality score
- ++1.2 ft water clarity
- +Lower phosphorus (41 vs 48.8 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.