1
CSag Quarry East Lake
Cook County, Wisconsin · 1.9 mi from Bullfrog Lake
- +Higher grade (D → C)
- ++4 ft water clarity
- +Lower phosphorus (30.5 vs 40.5 µg/L)
Cleaner Lakes Than Bullfrog Lake
2 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Bullfrog Lake carries a Grade D (Poor) water quality score. Within 30 miles, 2 lakes hold a higher grade. Sag Quarry East Lake (Cook County, Grade C, 1.9 mi away) is the closest meaningful upgrade.
2
CSag Quarry West Lake
Cook County, Wisconsin · 2.1 mi from Bullfrog Lake
- +Higher grade (D → C)
- ++2.8 ft water clarity
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.