How to Read Your Water Quality Report (CCR)

Every community water system in the US must deliver a Consumer Confidence Report — a CCR, the annual water quality report — to its customers by July 1, covering the previous calendar year's testing. If you just moved, you can pull your new system's report from the utility's website or EPA's CCR search tool without waiting for a bill, and EPA's SDWIS database will show the system's violation history going back years.

The first problem after a move is that you may not know which system serves you. The water bill names it; if you don't have one yet, your state drinking water program or EPA's Safe Drinking Water Information System (SDWIS) can locate it by city or county. SDWIS tracks roughly 150,000 public water systems nationwide, including the community systems that serve homes. Match the system name in SDWIS to the name on the CCR — that's your cross-check that you're reading the right report.

The heart of a CCR is a table: each detected contaminant, the level found, the legal limit, and whether there was a violation. The two columns that confuse everyone are MCLG and MCL. MCLG is the Maximum Contaminant Level Goal — a health-based target with no enforcement behind it, often set at zero. MCL is the Maximum Contaminant Level — the enforceable legal limit. A detection above zero but below the MCL is legal and extremely common; a detection above the MCL is a violation. Don't panic at the word 'detected'; look at the column that says whether a limit was exceeded.

Lead and copper work differently — there is no MCL. Instead there's an action level: for lead, 15 parts per billion measured at the 90th percentile of sampled household taps, meaning one in ten sampled homes can be higher without triggering action. Recent federal rule changes are lowering the lead action level to 10 ppb, with compliance dates still phasing in, so check your state's status. The deeper point: lead usually enters water from service lines and home plumbing, not the treatment plant, so a passing system result says little about your specific tap. Utilities were also required to complete initial lead service line inventories in late 2024 — ask your new utility whether your line is on it.

Violations come in two flavors and they are not equally alarming. Health-based violations — an exceeded MCL or a failed treatment technique — are the serious category. Monitoring and reporting violations mean the system missed a required test or filing. One paperwork lapse is noise; a multi-year pattern of monitoring violations is a signal that the system is under-resourced, and that pattern is exactly what SDWIS makes visible.

PFAS deserves its own line. PFAS — per- and polyfluoroalkyl substances, the so-called forever chemicals — got their first national drinking water limits in 2024, including 4 parts per trillion for PFOA and PFOS. Compliance deadlines have shifted since the rule was finalized, so treat the limits as incoming rather than fully enforced, but many utilities already publish PFAS sampling results in their CCRs. If yours doesn't, ask the utility directly; many have data they haven't surfaced.

None of this applies to private wells. No CCR, no SDWIS entry, no regulator — testing is entirely the owner's job. The standard advice is an annual test for coliform bacteria and nitrate, plus region-specific concerns like arsenic, uranium, or radon in water, which vary widely by local geology. State health department labs often run these tests cheaply, and a well test belongs in the first month of any move to a well-served home.

As a practical matter for movers: read the new system's latest CCR before or during move-in week. If the home was plumbed before the 1986 lead-free rules, or the area has known lead service lines, order a certified-lab tap test — commonly a few tens of dollars, varies by lab — because it answers the one question no system-level report can. LocateFlow's New Home Dossier surfaces the EPA-recorded water system and its reported violation history for an address; that's system-level, reported data about the utility, not a measurement of your tap.

First, identify your water system through your bill or SDWIS. Second, pull the latest CCR and check the violation column before anything else. Third, distinguish health-based violations from paperwork ones, and look for multi-year patterns. Fourth, if the home predates 1986 or the area has lead service lines, order your own tap test. Fifth, on a private well, schedule a coliform and nitrate test now and repeat annually.