Also detected, no federal limit: PFPeA.
Is there PFAS in Cottonwood Municipal Water Cw1 water?
Yes, at low levels. 1 PFAS was detected, all below EPA's 2024 limits.
Cottonwood Municipal Water Cw1 is a public water system drawing on groundwater, based in Cottonwood, Arizona, serving about 11,023 people. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 10 times across 5 sampling points between Mar 2025 and Sep 2025.
Every PFAS detected
| PFAS | Detected | Highest | Worst point avg | EPA limit |
|---|---|---|---|---|
| PFPeA Perfluoropentanoic acid |
1 of 10 | 3.2 ppt | 1.6 ppt | none |
Not detected: PFMBA, PFBA, NMeFOSAA, NEtFOSAA, PFTrDA, PFTA, PFHpS, PFPeS, 4:2 FTS, PFEESA, PFUnA, PFMPA, 8:2 FTS, NFDHA, 6:2 FTS, ADONA, 11Cl-PF3OUdS, PFHxA, PFDoA, PFDA, PFOA, PFOS, PFNA, PFHxS, PFHpA, PFBS, HFPO-DA, 9Cl-PF3ONS.
Lithium, tested in the same program: highest 51.5 ppb, detected in 10 of 10 samples. EPA's health-based screening level is 10 ppb.
What the EPA limits mean here
In April 2024 EPA set enforceable limits of 4 ppt for PFOA and PFOS, 10 ppt each for PFHxS, PFNA and GenX, and a hazard index of 1 for mixtures. Utilities were given until 2029 to comply. In May 2026 EPA proposed keeping only the PFOA and PFOS limits and moving that deadline to 2031. Until that proposal is final, the 2024 limits stand.
Compliance is judged on a running annual average at each entry point, so we show the average at this system's worst sampling point next to its single highest result. UCMR 5 results do not by themselves put a utility in or out of compliance.
What you can do at home
Levels here are under EPA's limits, so no treatment is required. If you want them lower anyway, a certified reverse osmosis system under the sink handles drinking water, and a whole-house carbon filter also takes out the chlorine or chloramine your utility adds.
Other systems in Arizona
- Arizona Water CO - Oracle none detected
- Johnson Util - Anthem at Merrill Ranch above an EPA limit
- Festival Ranch none detected
- Beardsley Water Company 1 none detected
- Tucson Water Corona De Tucson none detected
- Arizona Water CO - Sedona above an EPA limit
All 152 tested systems in Arizona
ZIP codes served
86326
As reported by the utility to EPA. Neighbouring ZIPs are often split between systems; your water bill names yours.
Cite this page
Well & Tap. "PFAS in Cottonwood Municipal Water Cw1 water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID AZ0413025. https://wellandtap.com/pfas/arizona/cottonwood-municipal-water-cw1/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID AZ0413025). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.