Best Water Quality Counties in Hawaii
EPA drinking water health violations and safety grades Compare rankings across all 5 counties.
All Hawaii Counties Ranked
| # | County | Water Quality Score | Overall Score |
|---|---|---|---|
| 1 | Kauai County, HI | 86 | 50.2 |
| 2 | Maui County, HI | 86 | 46.4 |
| 3 | Honolulu County, HI | 71.9 | 47.5 |
| 4 | Hawaii County, HI | 70.6 | 47.5 |
Data Source
Water Quality data from WaterByCounty. See full details at WaterByCounty. Data updated February 2026.