How to Read a CCR
A Consumer Confidence Report is dense by design. Here's what the key terms actually mean.
Short answer: A CCR lists detected substances against legal limits (MCLs) and health goals (MCLGs), plus any violations. A number below the MCL is compliant; it does not automatically mean "perfect," and a number above a health goal but below the MCL is still legal.
| Term | What it means |
|---|---|
| MCL | Maximum Contaminant Level — the highest level legally allowed in delivered water. |
| MCLG | Maximum Contaminant Level Goal — the public-health target, not an enforceable limit. Often set at zero for carcinogens. |
| Action Level | A threshold that triggers required treatment or other action (used for lead and copper rather than a single MCL). |
| Treatment Technique | A required treatment process used instead of an MCL when reliably measuring a contaminant at low levels isn't practical. |
| Violation | A failure to meet a legal requirement — a monitoring, reporting, or MCL violation, each meaning something different. |
| Range / Average | The lowest and highest detected results during the reporting period, and the average across all samples. |
| Sampling Period | The time window the reported results cover — check this against the report's issue date. |
Common mistakes
- Assuming any detected substance means the water is unsafe
- Confusing the MCLG (a goal) with the MCL (the enforceable limit)
- Treating a distribution-system result as proof about your own building's plumbing
- Ignoring the sampling period and treating an old range as current
When professional help is appropriate
If your CCR shows a violation or you're unsure what a result means for your household, ask your utility directly, or consult a water-treatment provider once you know the specific contaminant and level involved.
Official sources
- U.S. EPA Consumer Confidence Report guidance
- NJDEP Division of Water Supply & Geoscience
Related
Does a detected contaminant below the MCL mean my water is unsafe?
No. A result below the MCL is legally compliant. The MCLG is a separate, more conservative health target, not a pass/fail line.
This page provides general educational information and is not medical or regulatory advice.
Last reviewed: 2026-07-11. Report a correction.