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EPA UCMR5 · CITY REPORTS
Worst cities for PFAS in tap water
Two lists: cities with regulated PFAS over EPA MCLs (PFOA, PFOS, PFHxS, etc.), and cities with the highest unregulated peaks where MCL violation counts are still zero (e.g. high 6:2 FTS). For raw PWSID leaderboards see top 10 systems over MCL and top 50 peak readings.
TOP 20 — PFAS MCL VIOLATIONS (TRACKED CITIES)
#1
Pensacola, FL4 MCL flags
Worst regulated: 6:2 FTS at 220 ppt
220 ppt peak
#2
Rochester, NY3 MCL flags
Worst regulated: PFHxA at 160 ppt
160 ppt peak
#3
Newark, NJ3 MCL flags
Worst regulated: PFNA at 73.3 ppt
73.3 ppt peak
#4
Boise, ID3 MCL flags
Worst regulated: PFNA at 51.0 ppt
51.0 ppt peak
#5
Fresno, CA3 MCL flags
Worst regulated: PFPeA at 47.0 ppt
47.0 ppt peak
#6
Sacramento, CA3 MCL flags
Worst regulated: PFOS at 41.4 ppt
41.4 ppt peak
#7
Greensboro, NC3 MCL flags
Worst regulated: PFOS at 35.6 ppt
35.6 ppt peak
#8
Grand Rapids, MI3 MCL flags
Worst regulated: PFHxS at 30.0 ppt
30.0 ppt peak
#9
Anaheim, CA3 MCL flags
Worst regulated: PFOS at 29.0 ppt
29.0 ppt peak
#10
Fort Worth, TX3 MCL flags
Worst regulated: PFHxS at 25.8 ppt
25.8 ppt peak
#11
Fayetteville, NC3 MCL flags
Worst regulated: PFOS at 21.8 ppt
21.8 ppt peak
#12
Reno, NV3 MCL flags
Worst regulated: PFOS at 20.0 ppt
20.0 ppt peak
#13
Hartford, CT3 MCL flags
Worst regulated: PFOS at 16.2 ppt
16.2 ppt peak
#14
Madison, WI2 MCL flags
Worst regulated: PFBA at 280 ppt
280 ppt peak
#15
Philadelphia, PA2 MCL flags
Worst regulated: PFOA at 235 ppt
235 ppt peak
#16
Miami, FL2 MCL flags
Worst regulated: 6:2 FTS at 190 ppt
190 ppt peak
#17
Birmingham, AL2 MCL flags
Worst regulated: PFBS at 155 ppt
155 ppt peak
#18
Hialeah, FL2 MCL flags
Worst regulated: 6:2 FTS at 91.1 ppt
91.1 ppt peak
#19
Des Moines, IA2 MCL flags
Worst regulated: PFBA at 60.0 ppt
60.0 ppt peak
#20
Knoxville, TN2 MCL flags
Worst regulated: PFBS at 49.0 ppt
49.0 ppt peak
TOP 20 — HIGHEST UNREGULATED PFAS PEAKS (NO MCL VIOLATION COUNT)
These peaks are still serious forever chemicals — they are not yet counted as federal MCL violations in UCMR5 violation fields.