What Tucson's 2024 Water Data Actually Shows

01

What you're looking at

Tucson Water — the City of Tucson's municipal system, EPA public water system ID AZ0410112 — delivers groundwater to 732,906 residents through 191,264 service connections. This guide reads only the public federal record for that system: the EPA's 2024 UCMR5 monitoring round for PFAS and the most recent Lead and Copper Rule results. It adds no outside claims, and every figure below traces to a dated EPA source.

02

What the records find

In the 2024 UCMR5 round, the two federally regulated forever chemicals — PFOA and PFOS — were not detected in any of 163 samples taken across 83 Tucson Water facilities, each measured against the 4.0 ng/L limit set in the 2024 federal PFAS rule. Of 29 PFAS compounds monitored, 27 were never detected. One short-chain compound, PFBA, was detected in a single sample at up to 8.1 ng/L; PFBA has no federal limit and is reported here only for transparency. For lead, the most recent Lead and Copper Rule round (2021–2023) recorded a 90th-percentile household result of 0.65 µg/L — about 4% of the 15 µg/L federal action level, and lower than every prior round back to 1992. Lead has no known risk-free level, so this figure is a system-wide signal, not a reading for any single home.

03

How strong the evidence is

Two of the four categories PurityMap scores were measured for Tucson: PFAS and metals (lead). Two everyday measures — water hardness and disinfectant type (chlorine vs. chloramine) — are not published in the federal datasets. They appear in Tucson Water's own annual Water Quality Report, which is not yet on file here. Rather than estimate them, PurityMap marks both as pending and shows no number until it can cite one. The PFAS data is from 2024 and the lead data from the 2021–2023 period — both recent, though, like all monitoring, they describe the dates sampled.

Confidence is reported separately from the score. Tucson's record is rated moderate confidence because two of four categories are still pending a source.

04

What this means for your tap

The federal record describes treated water as the utility delivers it to the distribution system. It cannot describe what happens inside your home's plumbing. Lead in particular usually enters at the tap — from lead service lines, older solder or brass fixtures, most common in homes built before 1986 — which is why a low system-wide lead result does not rule out lead at an individual older tap. If you rent, or your address sits near a system boundary, confirm your actual supplier on your utility bill before acting on any single finding.

05

What to do next

To go deeper, open the full Tucson city water report to see each finding with its EPA source and date, or read the detailed PFAS results for Tucson and lead results for Tucson on their contaminant pages. If you have older plumbing and want to reduce potential lead at the tap, a filter certified to NSF/ANSI 53 for lead reduction is a low-cost option; the only way to know your own tap is a certified home test. PurityMap may earn an affiliate commission on some product links, at no cost to you, and points to certifications rather than brands.

06

What this report can't tell you

Read the two limits above together with the data. A national or utility-level record is a strong starting point, but it is not a substitute for testing your own address when you have a specific reason to.

A 'not detected' result means a contaminant was below the lab's reporting limit on the day sampled — not that it is certainly zero. A 'pending' category means it was not in the federal data we read, not that it is a problem. Neither is a verdict on the water.

07

Health disclaimer

This article summarizes public monitoring records and general information about drinking-water contaminants. It is not medical advice and does not determine whether any water is fit for a specific person. For health questions about lead, PFAS or other exposures — especially for infants, during pregnancy, or with a medical condition — consult a licensed healthcare professional, and contact Tucson Water or a certified laboratory for testing specific to your address.