The cleanest drinking water in America comes from counties with both perfect violation records and top-tier quality scores. These counties have water systems that not only avoid compliance issues but consistently deliver water that ranks in the top 10% nationally.
Using EPA SDWIS data, we identified the counties with zero health violations AND a water quality score of 90 or above — the strictest standard for clean drinking water.
The Counties with the Cleanest Drinking Water
These counties combine zero health violations with A-grade water quality scores:
| Rank | County | State | Score | Grade | Violations |
|---|
Methodology
Counties qualify for this ranking only if they have zero health-based violations AND a water quality score of 90 or above (A grade). Counties are ranked by water quality score in descending order. All data comes from the EPA SDWIS via the ECHO API.
Data source: U.S. Environmental Protection Agency, Safe Drinking Water Information System (SDWIS) Federal Reporting Services, accessed via ECHO API. All figures are estimates based on publicly available compliance data and may differ from other published analyses due to methodology differences.