How to Read a Consumer Confidence Report

A Consumer Confidence Report (CCR), now formally called an Annual Drinking Water Quality Report, is your utility's yearly summary of what it found in the water it delivered last year.

It covers the water leaving the treatment plant and, in most systems, results from within the distribution system. It does not describe the plumbing inside your building, which is where lead usually enters.

Contaminant: the substance measured. Detected level: what the lab actually found. MCL or Action Level: the legal limit. Range or highest result: how much it varies across the year.

MCL is the enforceable maximum contaminant level. MCLG is the non-enforceable health goal — for some contaminants it is zero, which is why a "detected" entry can still be fully compliant.

"ND" means not detected at the lab's reporting limit, not "zero and therefore nothing exists." The reporting limit itself tells you the smallest amount the test could see.

Lead and copper are regulated by action levels rather than MCLs: the utility must act when the 90th-percentile sample exceeds the level, but individual homes can still be above it.

That is why a report showing compliance and a home test showing lead are not a contradiction. The report describes the system; the home test describes your tap.

Violations and health effects language: if the utility had a monitoring or treatment violation, it must say so. Read it before anything else.

Unregulated contaminant monitoring: utilities often report PFAS, manganese, or other unregulated results here, with no legal limit attached. Those numbers are useful even without a limit.

Source water and treatment changes: a new source, a blended supply, or a switch in disinfectant explains most sudden taste and odor complaints.

Write down the contaminants that were detected at a meaningful fraction of the limit, then check whether your utility notes any treatment change.

Compare that list against a filter's certification: a 42 claim addresses chlorine taste, a 53 claim addresses named health contaminants, and a 58 claim belongs to RO systems.

If the report is clean and the complaint is taste, you may only need a 42-claimed pitcher or faucet filter — and you can skip the marketing arms race.