Lakes by State
LakeQuality grades 5,469 lakes across 12 states and 520 counties. Pick a state to see its cleanest lakes, county rankings, and full report cards.
| State | Lakes | Counties | Avg Grade | A-Grade | Cleanest Lake |
|---|---|---|---|---|---|
| Minnesota | 2,403 | 75 | C | 639 | East Fox Lake |
| Wisconsin | 1,422 | 69 | C | 455 | Geneva Lake |
| Michigan | 628 | 71 | B | 202 | Windover Lake South Basin; Freeman Township |
| Missouri | 317 | 82 | C | 17 | Lake Capri |
| New York | 189 | 48 | C | 60 | Blue Mtn Lake |
| Iowa | 170 | 75 | D | 4 | West Okoboji Lake |
| North Dakota | 150 | 50 | C | 11 | Wood Lake |
| Illinois | 144 | 45 | D | 5 | Diversey Harbor Lake |
| Indiana | 22 | 63 | D | 1 | Middle Lagoon Lake |
| Ohio | 17 | 13 | D | 0 | Caesar Creek Lake |
| South Dakota | 4 | 13 | D | 1 | Canyon Lake |
| Pennsylvania | 3 | 8 | D | 0 | Lake Wallenpaupack |
Minnesota
2,403 lakes graded across 75 counties
Wisconsin
1,422 lakes graded across 69 counties
Michigan
628 lakes graded across 71 counties
Missouri
317 lakes graded across 82 counties
New York
189 lakes graded across 48 counties
Iowa
170 lakes graded across 75 counties
North Dakota
150 lakes graded across 50 counties
Illinois
144 lakes graded across 45 counties
Indiana
22 lakes graded across 63 counties
Ohio
17 lakes graded across 13 counties
South Dakota
4 lakes graded across 13 counties
Pennsylvania
3 lakes graded across 8 counties
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