Does a detection mean the water is unsafe or out of compliance?

No. UCMR 5 is monitoring data and does not indicate compliance or noncompliance with any drinking-water standard. It reports the highest single detected result at the entry point, which is information you can act on by testing your own tap and choosing a certified filter.

PFAS detected in Arizona water systems

Q: Which Arizona water systems had PFAS detected in EPA UCMR 5?

EPA UCMR 5 detected PFOA or PFOS at or above 6 parts per trillion in 13 large Arizona public water systems (each serving more than 10,000 people). Select a system to see the specific PFAS and highest levels detected.

EPA UCMR 5 monitoring (2023–2025) detected PFOA or PFOS at or above 6 parts per trillion in these 13 large Arizona public water systems, each serving more than 10,000 people. Select a system to see exactly what was detected and the certified filters that reduce it.

Arizona systems, highest detections first

Water system	PFOA (ppt)	PFOS (ppt)	vs. 4 ppt reference
Tempe City of	38.7	55.8	13.9×
Payson Town of	40.9	42.2	10.6×
Liberty Water Rio Rico	10	40.9	10.2×
Marana Municipal - Marana	6.3	17.9	4.5×
Liberty Water Lpsco	10.2	14.1	3.5×
City of Avondale	13.5	11.7	3.4×
Prescott City of	11.4	8.7	2.9×
Arizona Water Co - Sedona	10	6	2.5×
Gilbert, Town of	6.5	9.8	2.5×
Goodyear Water Department	4.8	7.9	2×
Epcor Water - Mohave	5.3	7.3	1.8×
US Army Fort Huachuca	7	6.5	1.8×
Flowing Wells Irrigation District	5	6	1.5×

Highest single EPA UCMR 5 detections (2023–2025), in parts per trillion. The last column is the multiple of the 4 ppt federal reference level for PFOA/PFOS — shown as context only, not a compliance or health determination. — means the compound was not detected at or above 6 ppt.

Not sure what's in your own water? Test it first, then run the selector for a recommendation matched to your home, or read what PFAS is and how it's removed.