Top 10 Most PFAS-Contaminated Cities in America (2026 EPA Data)
EPA UCMR5 monitoring revealed which US water systems have the highest PFAS — regulated MCL violations and peak readings. Sugar Land TX leads Texas at 672 ppt 6:2 FTS. Here are the worst 10 — and what residents can do.
In 2024, the EPA set its first-ever legal limits for PFAS "forever chemicals" in drinking water — 4 parts per trillion for PFOA and PFOS. Within months, it became clear that thousands of US water systems were already over the limit. The EPA's UCMR5 monitoring program tested over 6,000 public water systems. The results were alarming. Here are the 10 most contaminated cities based on confirmed EPA data.
For city-by-city grades, contaminant tables, and filter picks, start with our Sugar Land water quality report — 672 ppt 6:2 FTS peak in EPA monitoring (highest in Texas).
#1 — Sugar Land, TX: 672 ppt 6:2 FTS (peak reading)
Sugar Land has the highest peak PFAS reading of any large Texas water system in UCMR5: 672 ppt of 6:2 FTS — a compound not yet covered by the EPA's six regulated PFAS limits. PFOA was also found at 4.1 ppt (at the 4 ppt federal limit). Industrial activity in the Brazos River corridor is the likely source. ~91,000 residents. See the full Sugar Land water report → · Regulated MCL rankings →
#2 — Columbus, OH: regulated PFAS above EPA limits
Columbus Public Water System (OH2504412) had regulated PFAS above EPA MCLs in UCMR5 monitoring, with an 18.2 ppt peak reading. The Scioto River — Columbus's primary source — has documented PFAS from upstream manufacturing. Columbus serves over 900,000 residents. See the full Columbus water report →
#3 — Pensacola, FL: 220 ppt (4 MCL violations)
The Emerald Coast Public water systems Authority (ECUA) serving Pensacola and Escambia County tested at 220 ppt across four PFAS compounds above EPA limits: PFHxS (55.3 ppt — 5.5× the limit), PFOS (35.7 ppt), PFOA (25.8 ppt), and PFNA (16.2 ppt). The contamination is directly linked to AFFF firefighting foam use at Eglin Air Force Base over several decades. See the full Pensacola water report →
#4 — Miami-Dade, FL: 190 ppt (4 MCL violations)
Miami-Dade Water and Sewer Authority (MDWASA) — serving 2.8 million people — tested at 190 ppt total PFAS with PFOS (33 ppt), PFOA (14 ppt), PFHxS (9.4 ppt), and PFNA (6.5 ppt) all above EPA MCLs. The Biscayne Aquifer, one of the most productive aquifer systems in the US, is the primary source — and one of the most vulnerable to surface contamination. See the full Miami water report →
#5 — Fort Worth, TX: 102 ppt
Fort Worth water tested at 102 ppt total PFAS, with PFHxS (4.5 ppt) and PFOS (4.8 ppt) above EPA MCLs. Fort Worth draws from the Trinity River and Eagle Mountain Lake — surface water sources with documented PFAS from military installations and industrial facilities upstream. See the full Fort Worth water report →
#6 — Sacramento, CA: 41 ppt + Lead at 70 ppb
Sacramento has a dual contamination problem: PFAS at 41.4 ppt (three MCL violations) and lead at 70 ppb — nearly 5 times the EPA action level of 15 ppb. This combination of PFAS and lead contamination makes Sacramento one of the most concerning water systems in California. Only reverse osmosis removes both. See the full Sacramento water report →
#7 — Dallas, TX: 18 ppt (2 MCL violations)
Dallas Water Public water systems tested at 18.2 ppt total PFAS with PFOA (6.3 ppt), PFOS (5.1 ppt), and PFHxS (3.8 ppt) above or near EPA MCLs. Dallas also uses chloramine for disinfection — standard carbon filters don't remove it. See the full Dallas water report →
#8 — Parkersburg, WV: 179 ppt (DuPont legacy)
Parkersburg is where the PFAS crisis started. DuPont's Washington Works plant discharged PFOA into the Ohio River for 50+ years. Current UCMR5 data still shows PFOA at 179.5 ppt — 45× the EPA limit. This contamination inspired the film Dark Waters and the largest PFAS class-action settlement in US history. See the full Parkersburg water report →
#9 — NYC: 106 ppt PFOS (26× the limit)
New York City's water system — which serves 8.3 million people — shows PFOS at 106 ppt in federal monitoring, more than 26 times the EPA's 4 ppt legal limit. PFOA was also detected at 27.8 ppt and PFHxS at 51.6 ppt. The Catskill reservoirs that supply NYC were once considered pristine. See the full NYC water report →
#10 — Philadelphia, PA: 235 ppt
Philadelphia's water system tested at 235 ppt total PFAS in the UCMR5 dataset. The Delaware River — Philadelphia's source — receives upstream industrial discharge from New Jersey and Pennsylvania manufacturing corridors. Philadelphia already made the list for lead service lines citywide. See the full Philadelphia water report →
Also elevated: Austin, Fresno, and Fairfax County
These major metros did not make the top 10 by peak reading alone, but EPA UCMR5 still flagged regulated PFAS above legal limits — worth checking if you live there:
- Austin, TX (8.4 ppt, PFOS above MCL) — Austin water quality report
- Fresno, CA (47 ppt, 3 MCL violations) — Fresno water quality report
- Fairfax County, VA (21.9 ppt) — Fairfax County water quality report
What to Do If Your City Is on This List
For renters and apartment dwellers: the Waterdrop K19-S countertop RO ($249) requires zero installation and removes 99%+ PFAS. For homeowners: the Waterdrop G3P600 under-sink RO ($439) or the G3P600 ($439) are the best under-sink options.
Not sure what's in your specific water? Enter your ZIP at WaterCheckup for a free city-level PFAS report from EPA data. Or get a certified mail-in test from Tap Score for a comprehensive panel covering 100+ contaminants.
Frequently asked questions
Which US city has the most PFAS in its tap water?
It depends how you rank. For peak UCMR5 readings, Sugar Land, Texas has 672 ppt of 6:2 FTS — the highest peak of any large Texas system (6:2 FTS is not yet EPA-regulated). For regulated MCL violations, Parkersburg WV (PFOA 179 ppt), NYC (PFOS 106 ppt), and Pensacola FL (four compounds over limits) rank among the worst.
How do I know if my city has PFAS in the water?
The EPA's UCMR5 program tested over 6,000 public water systems for PFAS between 2023 and 2025. You can check your specific public water system's results for free at WaterCheckup.com — enter your ZIP code to see your public water system's PFAS levels, violations, and filter recommendations.
What removes PFAS from tap water?
Reverse osmosis (RO) certified to NSF/ANSI 58 is the gold standard for PFAS removal, removing 99%+ of all PFAS compounds. Some NSF P473-certified pitcher filters also remove PFAS. Standard carbon filters, including Brita, do NOT reliably remove PFAS.
Is the EPA enforcing PFAS limits in drinking water?
Yes — the EPA finalized its first-ever PFAS drinking water standards in April 2024, setting MCLs of 4 ppt for PFOA and PFOS and 10 ppt for PFNA, PFHxS, and HFPO-DA. Public water systems have until 2029 to comply. Many currently exceed these limits.
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