Arizona water quality by city

By Daryna Klochko · Data checked Oct 15, 2026
Short answer

We cover 4 Arizona cities so far: Flagstaff, Phoenix, Scottsdale and Tucson. Statewide, EPA’s UCMR 5 testing covered 152 water systems. Of these, 57 had at least one PFAS detected, and 25 had a PFOA or PFOS sample at or above 4.0 ppt, the level of the federal limit.

Systems tested152UCMR 5 · 68 large systems
Any PFAS detected5738% of systems tested
PFOA or PFOS ≥ 4 ppt25At least one sample, 2023–2025
Cities covered4Pages with full data

A single sample at or above 4.0 ppt is not a violation. The PFOA and PFOS limits apply to a running annual average, and utilities must comply from 2029. City numbers describe the water system, not your tap.

Arizona cities

Listed A–Z. We don’t rank cities: utilities sample in different years and at different points.

City of Flagstaff · 79,796 people

Flagstaff

Lead · 90th pct3.6 ppb PFAS · UCMR 5No PFOA/PFOS; 1 other PFAS HardnessNot reported EPA violations · 10 yrs72 (0 health-based) Phoenix Water Services · 1,695,000 people

Phoenix

Lead · 90th pct2.7 ppb PFAS · UCMR 5No PFOA/PFOS; 2 other PFAS HardnessNot reported EPA violations · 10 yrs4 (1 health-based) Scottsdale Water · 241,361 people

Scottsdale

Lead · 90th pct2.3 ppb PFAS · UCMR 5No PFOA/PFOS; 1 other PFAS HardnessNot reported EPA violations · 10 yrs18 (0 health-based) Tucson Water · 732,906 people

Tucson

Lead · 90th pct0.6 ppb PFAS · UCMR 5No PFOA/PFOS; 1 other PFAS HardnessNot reported EPA violations · 10 yrs146 (0 health-based)

Find your water system by ZIP

A ZIP code can be served by more than one system. Your water bill names yours.

PFAS testing in Arizona

Between 2023 and 2025, EPA’s fifth Unregulated Contaminant Monitoring Rule (UCMR 5) had 152 Arizona public water systems test for 29 PFAS and lithium. 57 systems (38%) reported at least one PFAS at or above the reporting level. 25 had at least one PFOA or PFOS sample at or above 4.0 ppt, the level of the federal limit.

Source: EPA UCMR 5 final occurrence data (Aug 2026 release). Counts exclude lithium.

PFAS testing in neighboring states: California, Nevada, New Mexico and Utah.

Sources

EPA UCMR 5 occurrence dataepa.gov EPA: find your utility’s water quality reportepa.gov How we researchMethod