Is there PFAS in Cross Valley Water District water?
Yes, at low levels. 3 PFAS were detected, all below EPA's 2024 limits.
Cross Valley Water District
Serves 24,695 people · 14 PFOA samples from 6 sampling points · May 2024 to Feb 2025
PFAS found, below EPA limits
PFOA Perfluorooctanoic acid
not detected
PFOS Perfluorooctanesulfonic acid
not detected
Hazard index GenX, PFBS, PFNA, PFHxS combined
not detected
Also detected, no federal limit: PFBS, PFHxA, PFPeA.
Cross Valley Water District is a public water system drawing on surface water, based in Snohomish, Washington, serving about 24,695 people, including Bothell, Woodinville, Monroe, Snohomish. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 14 times across 6 sampling points between May 2024 and Feb 2025.
Every PFAS detected
Not detected: PFEESA, PFBA, 8:2 FTS, PFMBA, 4:2 FTS, NFDHA, PFPeS, PFHpS, PFTrDA, NMeFOSAA, NEtFOSAA, HFPO-DA, PFTA, 6:2 FTS, PFMPA, PFUnA, ADONA, PFHpA, PFHxS, PFNA, PFOA, PFDA, PFDoA, 9Cl-PF3ONS, PFOS, 11Cl-PF3OUdS.
Lithium, tested in the same program: not detected.
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 Washington
All 248 tested systems in Washington
ZIP codes served
98012 98072 98272 98296
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 Cross Valley Water District water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID WA5316270. https://wellandtap.com/pfas/washington/cross-valley-water-district/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID WA5316270). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
