Drinking Water Statistics
Data and trends from 433,347 public water systems and 12,049,741 EPA violations across states.
Violations by Year
Number of EPA drinking water violations recorded per year.
Top Contaminants
Most frequently cited contaminants in drinking water violations.
Health-Based vs Non-Health Violations
Proportion of violations that pose direct health risks versus monitoring and reporting issues.
About This Data
All data comes from the EPA's Safe Drinking Water Information System (SDWIS), published through ECHO at echo.epa.gov. The database contains 433,347 public water systems and 12,049,741 violations across states.
Health-based violations occur when a water system exceeds the Maximum Contaminant Level (MCL) for a regulated substance or fails to properly treat water. These violations indicate a direct health risk to consumers. Non-health violations involve monitoring, reporting, or administrative failures. Our database contains 1,632,684 health-based violations out of 12,049,741 total.