How do I read my water quality report (CCR)?
Short answer: Your Consumer Confidence Report (CCR) is the annual drinking water quality report your water system must send by July 1. Find it through your utility or EPA’s CCR search tool. Then compare each detected contaminant’s level with its legal limit (MCL) and its health goal (MCLG), and check for any violations.
Getting your report
EPA: "EPA requires community water systems to deliver a Consumer Confidence Report, also known as an annual drinking water quality report, to their customers." "Reports must be sent by your water supplier each year by July 1." If you did not get one, "You can either call your local water supplier or you may also find your report using EPA’s CCR search tool."
Renters often do not receive the report directly. Your landlord’s water utility publishes it, usually on its website.
What is in it
EPA lists what every report includes, among other items:
- The lake, river, aquifer or other source of your water.
- A brief summary of the risk of contamination of that source.
- The regulated contaminants found in your water.
- The potential health effects of any contaminant detected in violation of an EPA health standard, and what the system did to restore safe water.
- Phone numbers for more information, including EPA’s Safe Drinking Water Hotline, 1-800-426-4791.
Reading the table
Most reports show one row per detected contaminant. Look at the level detected (and its range), the MCL, which is the enforceable legal limit, and the MCLG, which is the non-enforceable health goal. Watch the units: ppm (parts per million) and ppb (parts per billion) differ by 1,000×. Also check the sample year and the "violation" column.
Lead and copper are reported differently: as the 90th percentile of household tap samples, compared with an action level rather than an MCL.
States can add their own information. In California, for example, reports also compare results with state Public Health Goals (PHGs). The State Water Board notes that "Readers interested in finding out more about the quality of their drinking water should refer to their water systems’ annual CCRs."
What Ground Report checks here, and what it doesn’t
The free score checks:
- Records for the public water system serving the address, from EPA’s Safe Drinking Water Information System (SDWIS), including lead and copper sampling and violations. For some systems it also uses the EWG Tap Water Database. Readings are compared against the named legal limit or health guideline.
It does not check:
- Water at your own tap, or plumbing inside your building.
- Private wells. These are labeled "Limited data".
- It does not replace your CCR. Your utility’s report is the official annual record.
Sources
- EPA — Consumer Confidence Reports (CCR)
- EPA — CCR Information for Consumers
- California State Water Board — Consumer Confidence Reports
Sources last reviewed 2026-10-26. Quotes are taken from the linked pages. This page is general information, not a home inspection, a water test or an official flood determination.