PFAS in US tap water: what EPA's final UCMR 5 data shows

Report published Nov 14, 2026 · EPA UCMR 5 final data file of Oct 15, 2026 (samples collected 2023–2025) · Method · By state

1,099 US community water systems serving 54.2 million people had PFAS above a 2024 federal limit in EPA's final round of nationwide testing: 11% of the 9,934 systems tested, in 47 states and territories.

9,934

community systems tested (serving 302.8 million people)

1,099

had an average above a federal limit

11%

of tested systems

54.2 million

people served by those systems

These are monitoring results, not violations: the limits apply from 2029, and EPA proposed in May 2026 to move the PFOA and PFOS deadline to 2031 and to rescind the other four limits (not final).

States with the highest share of systems above a limit

Connecticut 29 of 62 systems
46.8 %
New Jersey 110 of 245 systems
44.9 %
South Carolina 53 of 163 systems
32.5 %
Delaware 11 of 34 systems
32.4 %
Florida 124 of 394 systems
31.5 %
Massachusetts 75 of 261 systems
28.7 %
Rhode Island 7 of 26 systems
26.9 %
Pennsylvania 85 of 360 systems
23.6 %
North Carolina 66 of 285 systems
23.2 %
California 129 of 691 systems
18.7 %
New Hampshire 9 of 49 systems
18.4 %
Alabama 56 of 307 systems
18.2 %
Maryland 13 of 76 systems
17.1 %
Puerto Rico 15 of 96 systems
15.6 %
Arizona 21 of 159 systems
13.2 %

Share of tested community water systems with at least one PFAS average above a 2024 federal limit, top 15 states with 25 or more systems tested. EPA UCMR 5 final data, 2023–2025.

Chart data as a table

State	%
Connecticut · 29 of 62 systems	46.8
New Jersey · 110 of 245 systems	44.9
South Carolina · 53 of 163 systems	32.5
Delaware · 11 of 34 systems	32.4
Florida · 124 of 394 systems	31.5
Massachusetts · 75 of 261 systems	28.7
Rhode Island · 7 of 26 systems	26.9
Pennsylvania · 85 of 360 systems	23.6
North Carolina · 66 of 285 systems	23.2
California · 129 of 691 systems	18.7
New Hampshire · 9 of 49 systems	18.4
Alabama · 56 of 307 systems	18.2
Maryland · 13 of 76 systems	17.1
Puerto Rico · 15 of 96 systems	15.6
Arizona · 21 of 159 systems	13.2

Which limits were exceeded

PFAS	Federal limit	Systems above it	People served
PFOA 38.1 million people	4 ppt	755	38.1 million
PFOS 45.7 million people	4 ppt	849	45.7 million
PFHxS proposed for rescission 4.3 million people	10 ppt	63	4.3 million
PFNA proposed for rescission 163,771 people	10 ppt	9	163,771
GenX (HFPO-DA) proposed for rescission 190,246 people	10 ppt	8	190,246
Hazard Index proposed for rescission 4.6 million people	1	77	4.6 million

A system can be above more than one limit, so the rows add up to more than 1,099.

Results by state

Each state links to its dated report: chart, every system above a limit, downloadable data and a citation. Sorted by share of tested systems above a limit.

State	Share above	Above / tested	People served
Northern Mariana Islands 48,524 people	100.0%	1 / 1	48,524
Connecticut 1.2 million people	46.8%	29 / 62	1.2 million
New Jersey 5.1 million people	44.9%	110 / 245	5.1 million
South Carolina 2 million people	32.5%	53 / 163	2 million
Delaware 637,113 people	32.4%	11 / 34	637,113
Florida 9.7 million people	31.5%	124 / 394	9.7 million
Massachusetts 1.3 million people	28.7%	75 / 261	1.3 million
Rhode Island 207,864 people	26.9%	7 / 26	207,864
Pennsylvania 4.2 million people	23.6%	85 / 360	4.2 million
North Carolina 2.5 million people	23.2%	66 / 285	2.5 million
Guam 139,207 people	20.0%	1 / 5	139,207
California 8.9 million people	18.7%	129 / 691	8.9 million
New Hampshire 222,708 people	18.4%	9 / 49	222,708
Alabama 1.4 million people	18.2%	56 / 307	1.4 million
Maryland 162,211 people	17.1%	13 / 76	162,211
Puerto Rico 1.5 million people	15.6%	15 / 96	1.5 million
Arizona 845,012 people	13.2%	21 / 159	845,012
Georgia 1.3 million people	10.7%	27 / 252	1.3 million
Ohio 1.5 million people	10.6%	35 / 331	1.5 million
West Virginia 99,088 people	10.1%	10 / 99	99,088
New York 1.9 million people	9.6%	31 / 322	1.9 million
Wisconsin 184,985 people	9.2%	18 / 196	184,985
Washington 1.2 million people	8.2%	20 / 245	1.2 million
Nevada 488,064 people	8.1%	3 / 37	488,064
Virginia 1.8 million people	7.3%	12 / 164	1.8 million
Oregon 226,133 people	7.3%	9 / 123	226,133
Alaska 226,251 people	7.1%	2 / 28	226,251
Tennessee 344,152 people	6.2%	17 / 275	344,152
Nebraska 83,158 people	5.9%	3 / 51	83,158
Maine 22,328 people	5.1%	2 / 39	22,328
Minnesota 270,387 people	5.1%	10 / 197	270,387
Oklahoma 250,611 people	4.8%	8 / 167	250,611
Kentucky 199,762 people	3.9%	9 / 230	199,762
Idaho 21,500 people	3.3%	2 / 61	21,500
Wyoming 10,330 people	3.1%	1 / 32	10,330
Kansas 77,468 people	2.9%	3 / 102	77,468
Indiana 166,389 people	2.7%	6 / 219	166,389
Illinois 353,817 people	2.7%	13 / 479	353,817
Missouri 73,399 people	2.6%	6 / 227	73,399
Colorado 101,207 people	2.5%	4 / 158	101,207
Texas 2.8 million people	2.5%	28 / 1130	2.8 million
Mississippi 84,633 people	2.1%	5 / 235	84,633
Michigan 219,330 people	1.6%	5 / 311	219,330
Utah 14,975 people	1.6%	2 / 127	14,975
New Mexico 2,286 people	1.3%	1 / 77	2,286
Iowa 85,791 people	0.7%	1 / 151	85,791
Louisiana 6,354 people	0.4%	1 / 263	6,354
American Samoa 0 people	0.0%	0 / 1	0
Arkansas 0 people	0.0%	0 / 172	0
District of Columbia 0 people	0.0%	0 / 3	0
Hawaii 0 people	0.0%	0 / 44	0
Montana 0 people	0.0%	0 / 40	0
North Dakota 0 people	0.0%	0 / 41	0
South Dakota 0 people	0.0%	0 / 55	0
U.S. Virgin Islands 0 people	0.0%	0 / 2	0
Vermont 0 people	0.0%	0 / 34	0

The 25 largest systems above a limit

#	System	People served	Above the limit for
1	MDWASA – Main System Miami, Florida Above: PFOA, PFOS	2.4 million	PFOA, PFOS
2	Philadelphia Water Department Philadelphia, Pennsylvania Above: PFOA, PFOS	1.6 million	PFOA, PFOS
3	Fairfax County Water Authority Herndon, Virginia Above: PFOA	1.1 million	PFOA
4	Suffolk County Water Authority Brookhaven, New York Above: PFOA, PFOS	1.1 million	PFOA, PFOS
5	PRASA Metropolitano San Juan, Puerto Rico Above: PFOS	1.1 million	PFOS
6	City of Fort Worth Fort Worth, Texas Above: PFOA, PFOS, PFHxS, Hazard Index	955,900	PFOA, PFOS, PFHxS, Hazard Index
7	Aqua Pennsylvania Main System Northampton, Pennsylvania Above: PFOA, PFOS	822,600	PFOA, PFOS
8	Cincinnati Public Water System Cincinnati, Ohio Above: PFOS	800,000	PFOS
9	Veolia Water New Jersey Hackensack Hackensack, New Jersey Above: PFOA, PFOS	792,713	PFOA, PFOS
10	El Paso Water Utilities El Paso, Texas Above: PFOS	747,168	PFOS
11	City of Tampa Water Department Tampa, Florida Above: PFOS	733,886	PFOS
12	Palm Beach County Water Utilities West Palm Beach, Florida Above: PFOA, PFOS	671,114	PFOA, PFOS
13	New Jersey American Water – Raritan Monroe, New Jersey Above: PFOA, PFOS	615,430	PFOA, PFOS
14	City of Fresno Fresno, California Above: PFOA, PFOS, PFHxS, Hazard Index	545,970	PFOA, PFOS, PFHxS, Hazard Index
15	City of Sacramento Main Sacramento, California Above: PFOA, PFOS, PFHxS, Hazard Index	527,979	PFOA, PFOS, PFHxS, Hazard Index
16	Hillsborough County Water Resources – South-Central Riverview, Florida Above: PFOS	515,012	PFOS
17	Truckee Meadows Water Authority Reno, Nevada Above: PFOA, PFOS	442,000	PFOA, PFOS
18	Regional Water Authority New Haven, Connecticut Above: PFOA, PFOS	418,900	PFOA, PFOS
19	New Jersey American Water – Coastal North Howell, New Jersey Above: PFOA	377,613	PFOA
20	City of Vancouver Vancouver, Washington Above: PFOA, PFOS	373,047	PFOA, PFOS
21	City of Columbia Columbia, South Carolina Above: PFOA, PFOS	354,068	PFOA, PFOS
22	City of Anaheim Anaheim, California Above: PFOA, PFOS	350,254	PFOA, PFOS
23	City of Durham Durham, North Carolina Above: PFOS	333,490	PFOS
24	City of Greensboro Greensboro, North Carolina Above: PFOS	319,588	PFOS
25	City of Santa Ana Santa Ana, California Above: PFOA, PFOS	316,184	PFOA, PFOS

How this compares with EPA's own summary

EPA's UCMR 5 Data Summary (July 2026) counts every system that collected a full set of samples, including some that are not community water systems or are no longer active. This report covers active community water systems only, the ones that serve people where they live, so its counts are a little lower. Applied to every system in EPA's file, our method reproduces EPA's published counts, and a release is held if any count is off by more than 2% (how we check).

Limit	EPA Table 4 (all systems)	This report (community systems)
PFOA	779	755
PFOS	875	849
PFHxS	66	63
PFNA	9	9
GenX (HFPO-DA)	8	8
Hazard Index	80	77

EPA's figures add its large-system and small/medium-system counts from Table 4. EPA's summary reports counts by compound, and the 1,099 systems above any limit is our count from the same file.

Method

For each system we average each entry point's UCMR 5 results (non-detects count as zero, complete sets of samples only) and compare the highest entry-point average with the 2024 federal limit, using EPA's rounding. This is how EPA compares UCMR 5 results to the limits in its own data summary. Results are monitoring data from 2023–2025, not compliance determinations, and treatment installed since then is not reflected. Systems that were not tested have no result: not tested is not the same as not detected. Full method.

Data and how to cite it

Every state's systems as CSV: on each state report (for example New Jersey), with PFOA and PFOS averages and which limits each system is above.
EPA's source file: UCMR 5 occurrence data.

Suggested citation:

Tap Water Results, "PFAS in US tap water: what EPA's final UCMR 5 data shows" (published Nov 14, 2026, EPA data file of Oct 15, 2026). https://tapwaterresults.com/pfas/national-report/

You're welcome to quote and republish these figures with a link back. For reporters: questions about the data or a state you're covering, see contact.

Questions

How many US water systems have PFAS above the federal limits?

1,099 of the 9,934 community water systems EPA tested in 2023–2025 (11%) had at least one entry-point average above a 2024 federal PFAS limit. They serve 54.2 million people.

Does this mean these systems are breaking the law?

No. UCMR 5 results are monitoring data, not compliance determinations. Systems have until 2029 to meet the 2024 limits, and in May 2026 EPA proposed moving the PFOA and PFOS deadline to 2031 and rescinding the PFHxS, PFNA, GenX and Hazard Index limits. That proposal is not final.

Why are your counts different from EPA’s?

EPA’s summary counts every system that sampled, including some that are not community water systems or are no longer active. We cover active community water systems only, the ones that serve people where they live. Applied to EPA’s full file, our method reproduces EPA’s counts. How we check.

What about systems that were not tested?

EPA tested every community system serving more than 3,300 people and a representative sample of smaller ones. A system that was not tested has no federal result, which is not the same as having no PFAS.

Look up PFAS results for your water →

Source: U.S. EPA drinking water records and PFAS testing (UCMR 5). How we read the data.