Every public water utility in the United States is required by federal law to publish an annual Consumer Confidence Report — commonly referred to as a water quality report or CCR. It documents what was detected in your water supply during the previous year, at what concentrations, and how those levels compare to federal regulatory limits.
Most households receive it annually by mail or email and discard it without review. That is an understandable response to a document that was not designed for easy interpretation. This page explains what it contains and what to look for.
Where to Find It
Your utility's website is the most direct source — search your water provider's name alongside "water quality report" or "consumer confidence report." The Environmental Working Group's Tap Water Database at ewg.org/tapwater provides the same data in a more accessible format, cross-referenced against health guidelines rather than legal limits exclusively.
That distinction matters, and we will return to it.
What the Report Contains
A Consumer Confidence Report typically includes the following:
The water source — whether your supply originates from surface water such as a river or reservoir, or groundwater drawn from an aquifer. Source type influences the contaminant profile significantly.
Detected contaminants — listed by name alongside the concentration at which they were measured, expressed in milligrams per liter, micrograms per liter, or parts per trillion depending on the compound. The report also lists the EPA Maximum Contaminant Level — the legal threshold — for each regulated substance.
Violations — any instance in which a detected contaminant exceeded its regulatory limit during the reporting period.
Treatment information — the disinfection method your utility employs, including whether your supply uses chlorine or chloramines. That distinction has direct implications for the pre-filtration requirements of any system installed in your home.
The Distinction That Most Reports Obscure
Federal Maximum Contaminant Levels are legal thresholds. They are not health-optimized recommendations. For a number of regulated compounds — including several heavy metals and disinfection byproducts — the EPA's enforceable limit is set above the concentration at which peer-reviewed research identifies health risk.
The Environmental Working Group publishes independent health guidelines for over 200 contaminants. For many of those compounds, the EWG health guideline is considerably more stringent than the federal MCL. A report showing all contaminants within legal limits may still document exposures that warrant attention.
This is not a peripheral distinction. It is the reason a water quality report that appears compliant on its face can still indicate a meaningful filtration need.
Contaminants That Warrant Attention
These are the entries in your report that carry the most direct health relevance for residential buyers:
PFAS — If your report lists any PFAS compound — including PFOA, PFOS, or GenX — at any detected level, reverse osmosis is the EPA-recommended response. The EPA's current limit is 4 parts per trillion for PFOA and PFOS individually. Research indicates health effects at concentrations below that threshold.
Lead — Lead is not typically present in source water. It enters the supply through aging service lines and interior plumbing. If your report documents lead at any concentration above zero, the source is most likely your building's own infrastructure. An under-sink or whole-home RO system addresses this at the point of use.
Nitrates — A maximum contaminant level of 10 milligrams per liter applies federally. Nitrates originate primarily from agricultural runoff and are of particular concern for households with infants. Reverse osmosis removes 85 to 95 percent of nitrates. No carbon-based filter does.
Total Trihalomethanes and Haloacetic Acids — These are disinfection byproducts formed when chlorine reacts with organic matter in the water supply. Both are classified as probable human carcinogens at sustained exposure levels. Their presence in a report is not uncommon — it is a byproduct of the disinfection process itself.
Disinfectant type — If your report lists chloramines rather than chlorine as the primary disinfectant, note that standard carbon block filtration is insufficient for chloramine removal. Catalytic carbon is required. This detail is relevant to any system recommendation for your household.
What to Do With the Information
A water quality report establishes the baseline. It identifies what is present — though not always at the granularity a purchasing decision requires. Municipal reports reflect averages across the distribution system, not the specific conditions at your tap, which can be influenced by your building's age, plumbing materials, and proximity to the treatment facility.
If your report raises questions, or if you would prefer an interpreted analysis rather than working through the document independently, we provide a complimentary water quality review for your address as part of our consultation process.
[Book a Complimentary Water Analysis →]
For a detailed explanation of PFAS specifically — what it is, how it enters the water supply, and what the research indicates — see our PFAS page.