Arizona PFAS results from EPA's final data
Report published Nov 14, 2026 · EPA UCMR 5 final data file of Oct 15, 2026 (samples collected 2023–2025) · Method · National results →
21 Arizona water systems serving 845,012 people had PFAS above a 2024 federal limit in EPA's final round of nationwide PFAS testing: 13% of the 159 Arizona systems tested, compared with 11% nationally.
Highest PFOA or PFOS averages in Arizona
- City of Tempe Tempe · PFOS55.1 ppt
- Liberty Water Rio Rico Rio Rico · PFOS40.5 ppt
- Town of Payson Payson · PFOA39.7 ppt
- Marana Municipal – Hartman Vistas Marana · PFOS22.5 ppt
- EPCOR – San Tan Anthem San Tan Valley · PFOA18 ppt
- Marana Municipal – Marana Marana · PFOS17.9 ppt
- City of Avondale Avondale · PFOA12.2 ppt
- Liberty Water Lpsco Litchfield Park · PFOS11.8 ppt
- USAF Luke Air Force Base Litchfield Park · PFOS11.5 ppt
- City of Prescott Prescott · PFOA10.7 ppt
- Big Park Water Company Sedona · PFOA10.5 ppt
- Arizona Water Company – Sedona Sedona · PFOA9.7 ppt
- City of Globe Globe · PFOS9.45 ppt
- Town of Gilbert Gilbert · PFOS7.7 ppt
- Goodyear Water Department Goodyear · PFOS7.45 ppt
Chart data as a table
| System | ppt |
|---|---|
| City of Tempe · Tempe · PFOS | 55.1 |
| Liberty Water Rio Rico · Rio Rico · PFOS | 40.5 |
| Town of Payson · Payson · PFOA | 39.7 |
| Marana Municipal – Hartman Vistas · Marana · PFOS | 22.5 |
| EPCOR – San Tan Anthem · San Tan Valley · PFOA | 18 |
| Marana Municipal – Marana · Marana · PFOS | 17.9 |
| City of Avondale · Avondale · PFOA | 12.2 |
| Liberty Water Lpsco · Litchfield Park · PFOS | 11.8 |
| USAF Luke Air Force Base · Litchfield Park · PFOS | 11.5 |
| City of Prescott · Prescott · PFOA | 10.7 |
| Big Park Water Company · Sedona · PFOA | 10.5 |
| Arizona Water Company – Sedona · Sedona · PFOA | 9.7 |
| City of Globe · Globe · PFOS | 9.45 |
| Town of Gilbert · Gilbert · PFOS | 7.7 |
| Goodyear Water Department · Goodyear · PFOS | 7.45 |
Largest systems above a limit
| # | System | People served |
|---|---|---|
| 1 | Town of Gilbert Gilbert Above: PFOS | 247,600 |
| 2 | City of Tempe Tempe Above: PFOA, PFOS, PFHxS, Hazard Index | 165,000 |
| 3 | City of Avondale Avondale Above: PFOA, PFOS | 96,130 |
| 4 | Liberty Water Lpsco Litchfield Park Above: PFOA, PFOS | 57,070 |
| 5 | Goodyear Water Department Goodyear Above: PFOA, PFOS | 50,001 |
| 6 | City of Prescott Prescott Above: PFOA, PFOS | 42,217 |
| 7 | Bullhead City Mohave Water System Bullhead City Above: PFOS | 36,330 |
| 8 | Liberty Water Rio Rico Rio Rico Above: PFOA, PFOS | 17,960 |
| 9 | Town of Payson Payson Above: PFOA, PFOS, PFHxS, Hazard Index | 17,682 |
| 10 | Flowing Wells Irrigation District Tucson Above: PFOA, PFOS | 16,000 |
All 21 Arizona systems above a limit
Every Arizona community water system whose UCMR 5 results averaged above a 2024 federal PFAS limit, largest first. Systems that were not tested are not listed: not tested is not the same as not detected.
Full list: 21 systems, largest first
| System | People served |
|---|---|
| Town of Gilbert Gilbert Above: PFOS | 247,600 |
| City of Tempe Tempe Above: PFOA, PFOS, PFHxS, Hazard Index | 165,000 |
| City of Avondale Avondale Above: PFOA, PFOS | 96,130 |
| Liberty Water Lpsco Litchfield Park Above: PFOA, PFOS | 57,070 |
| Goodyear Water Department Goodyear Above: PFOA, PFOS | 50,001 |
| City of Prescott Prescott Above: PFOA, PFOS | 42,217 |
| Bullhead City Mohave Water System Bullhead City Above: PFOS | 36,330 |
| Liberty Water Rio Rico Rio Rico Above: PFOA, PFOS | 17,960 |
| Town of Payson Payson Above: PFOA, PFOS, PFHxS, Hazard Index | 17,682 |
| Flowing Wells Irrigation District Tucson Above: PFOA, PFOS | 16,000 |
| US Army Fort Huachuca Water System Sierra Vista Above: PFOA, PFOS | 15,603 |
| Marana Municipal – Marana Marana Above: PFOA, PFOS, PFHxS, Hazard Index | 15,162 |
| Arizona Water Company – Sedona Sedona Above: PFOA, PFOS | 12,104 |
| EPCOR – San Tan Anthem San Tan Valley Above: PFOA | 10,362 |
| Arizona Water Company – Bisbee Bisbee Above: PFOA | 8,590 |
| USAF Luke Air Force Base Litchfield Park Above: PFOA, PFOS | 8,440 |
| City of Globe Globe Above: PFOS, PFHxS, Hazard Index | 7,536 |
| Big Park Water Company Sedona Above: PFOA | 7,392 |
| Marana Municipal – Hartman Vistas Marana Above: PFOS | 5,408 |
| North Mohave Valley Water System Bullhead City Above: PFOS | 5,190 |
| Global Water – Farmers Water Company – Santa Rita Springs Sahuarita Above: PFOS | 3,235 |
The same list, with PFOA and PFOS averages, is in the data download.
Which limits were exceeded
| PFAS | Federal limit | Systems above it |
|---|---|---|
| PFOA 539,713 people | 4 ppt | 15 |
| PFOS 818,668 people | 4 ppt | 18 |
| PFHxS 205,380 people | 10 ppt | 4 |
| PFNA | 10 ppt | 0 |
| GenX (HFPO-DA) | 10 ppt | 0 |
| Hazard Index 205,380 people | 1 | 4 |
"–" in the table above means not detected. A system can be above more than one limit. EPA proposed in May 2026 to rescind the PFHxS, PFNA, GenX and Hazard Index limits. That proposal is not final.
Data and how to cite it
- Download every Arizona water system as CSV (PFOA and PFOS averages, systems above a limit, lead, violations).
- EPA's source file: UCMR 5 occurrence data.
Suggested citation:
Tap Water Results, "Arizona PFAS results from EPA's final UCMR 5 data" (published Nov 14, 2026, EPA data file of Oct 15, 2026). https://tapwaterresults.com/pfas/arizona/
You're welcome to quote and republish these figures with a link back. Questions from reporters: see contact.
Method
For each system we average each entry point's UCMR 5 results (non-detects count as zero, complete sets of samples only) and compare the highest entry-point average with the 2024 federal limit, using EPA's rounding. This is how EPA compares UCMR 5 results to the limits in its own data summary, and our national counts match EPA's published table within 2% (how we check). Results are monitoring data from 2023–2025, not compliance determinations, and treatment installed since then is not reflected. Full method.
Questions
How many Arizona water systems have PFAS above the limit?
21 of the 159 Arizona community water systems EPA tested in 2023–2025 (13%) had at least one entry-point average above a 2024 federal PFAS limit. They serve 845,012 people. Nationally the share is 11%.
Are these systems violating the law?
Not yet. Systems have until 2029 to meet the 2024 limits, and EPA has proposed moving the PFOA and PFOS deadline to 2031 and rescinding the other limits. EPA's UCMR 5 results are monitoring data and do not determine compliance.
Which systems were tested?
EPA's UCMR 5 tested every community water system serving more than 3,300 people and a representative sample of smaller ones. Systems that were not tested have no federal result, which is not the same as having no PFAS.
All Arizona water systems → · National results → · PFAS results for every state →
Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.