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WaterSafety

Health-Based Violation

The most serious type of drinking water violation — indicating that water quality has exceeded a maximum contaminant level or failed to meet a treatment requirement that directly protects health.

How It Works

Health-based violations include MCL violations (contaminant levels exceeding the legal limit), treatment technique violations (failure to maintain required treatment processes), and maximum residual disinfectant level violations. These are distinguished from monitoring violations (failing to test) and reporting violations (failing to report results), which are administrative in nature. A health-based violation means the water may not be safe to drink. Water systems with health-based violations must notify their customers — through boil-water advisories, do-not-drink orders, or public notices depending on the severity. Chronic health-based violations may trigger enforcement actions including fines, required treatment upgrades, or state takeover of the water system.

Related Terms

  • Maximum Contaminant Level (MCL)The highest level of a contaminant allowed in drinking water — set by the EPA and enforceable by law. Exceeding the MCL triggers a health-based violation.
  • Water Safety ScoreIsWaterSafe's proprietary A-F grade for water systems, based on health violations (40%), contaminant exceedances (30%), enforcement history (20%), and monitoring compliance (10%).
  • SDWIS (Safe Drinking Water Information System)The EPA database that tracks every public water system in the United States — violations, enforcement actions, contaminant levels, and system characteristics.

About This Definition

This definition is part of the IsWaterSafe Drinking Water Safety Glossary22 terms explaining water contaminants, treatment methods, and safety standards. Written for homeowners, renters, journalists, and public health professionals.