1
ABig Twin Lake
Langlade County, Wisconsin · 1.5 mi from Harper Lake
- +Higher grade (B → A)
- ++54.8 ft water clarity
- +Lower phosphorus (14.1 vs 27.5 µg/L)
Cleaner Lakes Than Harper Lake
5 higher-graded lakes within 30 miles, ranked by grade improvement and proximity.
Harper Lake carries a Grade B (Good) water quality score. Within 30 miles, 5 lakes hold a higher grade. Big Twin Lake (Langlade County, Grade A, 1.5 mi away) is the closest meaningful upgrade.
2
AArbutus Lake
Forest County, Wisconsin · 2.9 mi from Harper Lake
- +Higher grade (B → A)
- ++40 ft water clarity
- +Lower phosphorus (10.7 vs 27.5 µg/L)
3
ASt. Johns Lake
Forest County, Wisconsin · 4.5 mi from Harper Lake
- +Higher grade (B → A)
- ++24.3 ft water clarity
- +Lower phosphorus (14.8 vs 27.5 µg/L)
4
APickerel Lake
Forest County, Wisconsin · 1.1 mi from Harper Lake
- +Higher grade (B → A)
- ++23.6 ft water clarity
- +Lower phosphorus (20.4 vs 27.5 µg/L)
5
ACrane Lake
Forest County, Wisconsin · 2.5 mi from Harper Lake
- +Higher grade (B → A)
- ++12.9 ft water clarity
- +Lower phosphorus (22 vs 27.5 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.