Best Water Quality Counties in Maine
EPA drinking water health violations and safety grades Compare rankings across all 16 counties.
All Maine Counties Ranked
| # | County | Water Quality Score | Overall Score |
|---|---|---|---|
| 1 | Sagadahoc County, ME | 86 | 54.7 |
| 2 | York County, ME | 49.6 | 46.8 |
| 3 | Penobscot County, ME | 45.6 | 38.7 |
| 4 | Kennebec County, ME | 44.1 | 40.2 |
| 5 | Cumberland County, ME | 43.3 | 47.4 |
| 6 | Androscoggin County, ME | 38.5 | 38.2 |
| 7 | Lincoln County, ME | 36.4 | 54.2 |
| 8 | Oxford County, ME | 35.2 | 45.3 |
| 9 | Knox County, ME | 20.8 | 50.5 |
| 10 | Somerset County, ME | 16.7 | 41.3 |
| 11 | Aroostook County, ME | 15 | 48.7 |
| 12 | Franklin County, ME | 12.5 | 54.8 |
| 13 | Piscataquis County, ME | 11.6 | 49.7 |
| 14 | Waldo County, ME | 10.3 | 53.9 |
| 15 | Washington County, ME | 8.1 | 52.8 |
| 16 | Hancock County, ME | 8 | 51.2 |
Data Source
Water Quality data from WaterByCounty. See full details at WaterByCounty. Data updated February 2026.