Worst Tap Water in the United States
Tracking water systems under EPA enforcement for serious, ongoing violations of the Safe Drinking Water Act that potentially expose millions of Americans to health risks.
Understanding Serious Violators & Health Impacts
The EPA designates water systems as "serious violators" when they have persistent, unresolved problems with health-based standards, monitoring requirements, treatment techniques, or enforcement orders. These systems pose potential health risks to the communities they serve.
Health Concerns
- Immediate: Exposure to harmful contaminants
- Long-term: Chronic health issues
- Vulnerable: Greater impact on children & elderly
Our Analysis
- Identifies states with highest risk exposure
- Helps communities advocate for safer water
- Based on EPA enforcement data across all 50 states
Last updated: January 2025 • Next update: April 2025
Serious Violators
902
2.1% of all U.S. water systems
People Affected
5.4M
1.7% of U.S. population served
States Affected
47
Out of 50 U.S. states
Water Systems
43,447
Public water systems nationwide
Top 5 States Most Impacted by Serious Violators
These states have the highest percentage of their population served by water systems that are designated as "serious violators" of EPA drinking water regulations.