What counts as a health-based violation?
EPA ECHO describes health-based violations as violations of maximum contaminant levels, maximum residual disinfectant levels or treatment-technique rules. Monitoring, reporting, public-notice and recordkeeping violations are important but are separate categories.
How HomeNHealthy queries the data
The updater requests active community water systems in each state, then applies ECHO’s documented p_cs=H current-violation filter. It reports the number and percentage of systems returned without a current health-based violation. Automated checks reject negative counts, violation counts greater than total systems and the previous failure pattern in which an ignored filter made the two counts identical across the country.
Why the current figure is state-level
Public-water service territories do not reliably match city boundaries or ZIP codes. Until HomeNHealthy can map utilities at the PWSID level, state context is labeled as state context. It should not be read as a claim about Austin Water, Denver Water or any other named local supplier.
Does a violation mean tap water is unsafe today?
Not necessarily. Violation records have different start dates, statuses and corrective actions, and federal reporting can lag. A household should identify its serving system, read its Consumer Confidence Report and check current local notices.
What the number does not cover
- Private wells.
- Conditions in building plumbing.
- A contaminant measurement at a specific tap.
- Health standards that are not part of the regulatory query.