Skip to content

Drinking water quality

What is in your water, by the utility that delivers it

EPA Six-Year Review sample-level drinking water data + Consumer Confidence Report aggregation per community water system. Free, public, indexable. Built so a citizen, a city auditor, or a chemical procurement officer can answer the same question: which regulated contaminants does this system see, at what concentration, and how often.

For whom

  • Citizens asking what is in their tap water
  • City auditors + water-utility managers
  • Chemical suppliers tracking near-MCL contaminants
  • Infrastructure investors evaluating treatment-pressure sites
  • Grant writers citing per-system compliance trends

What you find

  • Per-utility regulated contaminant readings
  • MCL exceedance counts + near-MCL flags
  • State-cohort top-contaminant rankings
  • Source-water context (linked to existing climate + wastewater bands)
  • Citable EPA source URLs for every value

Where the data comes from

EPA Six-Year Review (SYR4)
EPA's national sample-level SDWA compliance dataset. Most recent release covers 2012-2019. Source for the per-utility contaminant ratios + state-cohort exceedance rankings. Next refresh: SYR5, expected 2029.
Consumer Confidence Reports (CCRs)
Annual mandatory publications each community water system produces. Source for the most-recent contaminant detection levels per utility. Coverage expands state-by-state as ingest lanes land.
SDWIS violations
EPA Safe Drinking Water Information System enforcement records. Already loaded on every per-utility profile.

Browse by state

To see one utility's full drinking-water quality detail, look it up by name on the muni search or land on any state page to drill in.