Is there PFAS in Cobb County water?
Yes, at low levels. 3 PFAS were detected, all below EPA's 2024 limits.
Cobb County
Serves 695,000 people · 4 PFOA samples from 1 sampling point · Aug 2023 to May 2024
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: PFBA, PFBS, PFHxA.
Cobb County is a public water system drawing on surface water, based in Marietta, Georgia, serving about 695,000 people, including Marietta, Roswell, Smyrna, Acworth, Austell, Mableton. Under EPA's Fifth Unregulated Contaminant Monitoring Rule it was tested for 29 PFAS and lithium 4 times across 1 sampling point between Aug 2023 and May 2024.
Every PFAS detected
Not detected: PFTrDA, ADONA, 9Cl-PF3ONS, 11Cl-PF3OUdS, PFUnA, PFDoA, PFDA, NEtFOSAA, HFPO-DA, PFTA, PFOA, PFNA, PFHxS, PFHpA, NMeFOSAA, NFDHA, PFOS, PFPeS, PFEESA, PFMBA, PFPeA, PFMPA, 8:2 FTS, 4:2 FTS, 6:2 FTS, PFHpS.
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 Georgia
All 256 tested systems in Georgia
ZIP codes served
30008 30060 30062 30064 30066 30067 30068 30075 30080 30082 30101 30102 30106 30126 30127 30141 30144 30152 30168 30188 30339
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 Cobb County water: EPA UCMR 5 results." Data: U.S. EPA Fifth Unregulated Contaminant Monitoring Rule, final release August 2026, PWSID GA0670003. https://wellandtap.com/pfas/georgia/cobb-county/
About this data
Source: U.S. EPA, UCMR 5 occurrence data, final release August 2026 (PWSID GA0670003). Population: EPA SDWIS. Averages count results below the reporting level as zero, the same convention EPA uses for running annual averages. Full method.
