PFAS · Arizona

PFAS in Arizona drinking water: EPA’s final survey results

EPA’s national PFAS survey (UCMR 5) tested 168 of the community water systems that serve homes in Arizona. 57 found at least one of 29 PFAS above the laboratory reporting level, and 21 had a PFOA or PFOS sampling-location yearly average at or above EPA’s 4.0 ppt limit. Samples were collected from January 2023 to June 2026.

In focus34%of surveyed systems found PFAS

Public records. Clearer context.

Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages

168

Arizona community systems in EPA’s survey

serving about 6,926,840 people

found at least one PFAS

34% of surveyed systems; about 5,243,426 people served

PFOA or PFOS yearly average at or above the MCL

compared the way EPA does: the average of a complete sampling set

160

lithium at or above EPA’s health reference level

lithium was part of the same survey

PFBS was the compound Arizona community systems found most often: 41 of 168 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in Arizona the share is 34%. The largest Arizona system with a detection, Phoenix City of, serves 1,695,000 people and found 2 of the 29 compounds.

Which PFAS were found most often in Arizona

Each row counts the Arizona community water systems where that compound was measured above the reporting level at least once. A detection is a measurement, not a violation: most of these compounds have no federal limit.

Compound	Systems where found	Systems tested	Share
PFBS	41	168	24%
PFPeA	33	168	20%
PFHxA	32	168	19%
PFHxS	27	168	16%
PFBA	24	168	14%
PFOA	20	168	12%
PFOS	20	168	12%
PFHpA	12	168	7%
PFPeS	3	168	2%
6:2 FTS	1	168	1%
PFDA	1	168	1%
PFNA	1	168	1%

Arizona systems with the most PFAS found

The 10 surveyed community water systems that found the most different PFAS, with PFOA and PFOS compared to EPA’s 4.0 ppt limits on the yearly average at the highest sampling location. Larger systems come first when counts tie.

Water system	People served	PFAS found (of 29)	PFOA	PFOS
Tempe City of AZ0407100	165,000	9	37.9 ppt at or above the MCL	55.2 ppt at or above the MCL
Payson Town of AZ0404032	17,682	9	39.7 ppt at or above the MCL	36.9 ppt at or above the MCL
Avondale City of AZ0407088	96,130	8	12.2 ppt at or above the MCL	10.3 ppt at or above the MCL
Liberty Water Lpsco AZ0407046	55,810	8	10.2 ppt at or above the MCL	11.8 ppt at or above the MCL
Arizona Water Co - Sedona AZ0403003	12,104	8	9.7 ppt at or above the MCL	5.2 ppt at or above the MCL
Prescott City of AZ0413045	42,217	7	10.7 ppt at or above the MCL	8.4 ppt at or above the MCL
Liberty Water Rio Rico AZ0412011	17,960	7	8.0 ppt at or above the MCL	40.5 ppt at or above the MCL
USAF Luke Air Force Base AZ0407305	8,440	7	9.7 ppt at or above the MCL	11.5 ppt at or above the MCL
Big Park Water Company AZ0413012	7,392	7	10.5 ppt at or above the MCL	2.1 ppt below the MCL
Gilbert, Town of AZ0407092	247,600	6	3.3 ppt below the MCL	7.7 ppt at or above the MCL

Counties with the most systems that found PFAS

Maricopa County 16 of 44 surveyed systems
Pima County 7 of 27 surveyed systems
Pinal County 5 of 17 surveyed systems
Mohave County 4 of 13 surveyed systems
Yavapai County 4 of 9 surveyed systems
Cochise County 4 of 8 surveyed systems
Gila County 4 of 4 surveyed systems
Coconino County 3 of 9 surveyed systems

How to read these numbers

UCMR 5 asked every community and non-transient non-community water system serving 3,300 or more people, and a sample of smaller ones, to test for 29 PFAS and lithium. EPA published the final data in August 2026; its samples were collected from January 2023 to June 2026. A system that was not in the survey has no result here; that is not the same as having no PFAS.

UCMR 5 is a one-time national monitoring survey. Its results do not indicate compliance or non-compliance with the PFAS Maximum Contaminant Levels, which are enforced on running annual averages and take effect in 2029 (EPA has proposed allowing extensions to 2031). A single result above a limit on this page is a measurement, not a violation.

See how to read UCMR 5 results and our methodology for how systems are matched to places.

After Arizona’s PFAS results

Find your system. Then read its report.

State recordsAll Arizona water recordsCounties, ZIP reports, lead results and violations for the whole state.FiltersChoosing a PFAS filterHow to check a filter’s certified PFAS reduction before you buy.Your utilityFind your annual water reportYour utility’s Consumer Confidence Report will list its own PFAS results and any treatment plans.

County pages

Arizona water records

Sources

EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Database prepared 2026-09-03.