Is there PFAS in Flowing Wells Irrigation District water?

Yes. EPA's final UCMR 5 results show Flowing Wells Irrigation District averaged 5.0 ppt of PFOA at its worst sampling point, 1.3 times the EPA limit of 4 ppt.

Flowing Wells Irrigation District is a public water system drawing on groundwater, based in Tucson, Arizona, serving about 16,000 people. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 12 times across 6 sampling points between Feb 2023 and Aug 2023.

Every PFAS detected

Not detected: 4:2 FTS, 6:2 FTS, PFBA, 8:2 FTS, HFPO-DA, ADONA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFMPA, PFNA, PFDoA, PFDA, PFUnA, PFMBA, PFEESA, PFPeS, PFTrDA, NEtFOSAA, NMeFOSAA, PFTA, NFDHA, PFHpA, PFHpS.

Lithium, tested in the same program: highest 228 ppb, detected in 11 of 12 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

Two routes work for PFAS. For drinking and cooking water only, a reverse osmosis system certified to NSF/ANSI 58 with a PFOA/PFOS reduction claim is the cheapest proven option. To treat every tap and shower, a whole-house carbon system with enough contact time works, but check that the maker has PFAS test data, not just a marketing claim. See the best filters for PFAS and how PFAS removal works.

Other systems in Arizona

• Florence Water Company 3 PFAS detected
• City of Buckeye Sonora - Sundance none detected
• Apache Junction Water District none detected
• Us Army Fort Huachuca above an EPA limit
• Grand Canyon National Park none detected
• City of Douglas none detected

All 152 tested systems in Arizona

ZIP codes served

85705

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 Flowing Wells Irrigation District water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID AZ0410051. https://wellandtap.com/pfas/arizona/flowing-wells-irrigation-district/

About this data

Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID AZ0410051). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.