Is there PFAS in City of Rockville water?
Yes, at low levels. 4 PFAS were detected, all below EPA's 2024 limits.
City of Rockville
Serves 52,000 people · 4 PFOA samples from 1 sampling point · Mar 2023 to Dec 2023
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: PFPeA, PFHxA, PFBA, PFBS.
City of Rockville is a public water system drawing on surface water, Maryland, serving about 52,000 people, including Rockville, Potomac. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 4 times across 1 sampling point between Mar 2023 and Dec 2023.
Every PFAS detected
Not detected: NEtFOSAA, PFDoA, PFDA, PFOS, PFHxS, PFHpA, NMeFOSAA, PFTrDA, PFOA, PFUnA, PFTA, PFEESA, PFNA, PFPeS, 11Cl-PF3OUdS, NFDHA, PFMBA, PFMPA, 8:2 FTS, 6:2 FTS, PFHpS, 9Cl-PF3ONS, ADONA, 4:2 FTS, HFPO-DA.
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 Maryland
All 83 tested systems in Maryland
ZIP codes served
20850 20851 20852 20854
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 City of Rockville water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID MD0150003. https://wellandtap.com/pfas/maryland/city-of-rockville/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID MD0150003). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
