Guides

Plain-English answers to the questions behind AquaCensus's data, each sourced to the agency records and linked to the pages that answer them.

• How to find out who supplies your drinking waterFind the public water system behind your tap: check your bill, learn the PWSID, and look up the system by state and county in EPA records.
• How to find and read your annual water quality reportEvery community water system must publish a yearly water quality report by July 1. Where to get yours and how to read the MCL, MCLG and detected levels.
• What a drinking water violation notice meansWhy water systems send violation notices, how the three notice tiers differ, what a 'we did not monitor' letter means, and how to check a record.