PFAS · Pennsylvania

PFAS in Pennsylvania drinking water: EPA’s final survey results

EPA’s national PFAS survey (UCMR 5) tested 360 of the community water systems that serve homes in Pennsylvania. 161 found at least one of 29 PFAS above the laboratory reporting level, and 85 had a PFOA or PFOS sampling-location yearly average at or above EPA’s 4.0 ppt limit. Samples were collected from January 2023 to April 2026.

In focus45%of surveyed systems found PFAS

Public records. Clearer context.

Data as of EPA UCMR 5 final release, August 2026 (file dated Aug 28, 2026) · EPA SDWIS 2026Q2 (file dated Jul 9, 2026). How we build these pages

360

Pennsylvania community systems in EPA’s survey

serving about 10,584,045 people

161

found at least one PFAS

45% of surveyed systems; about 5,635,378 people served

PFOA or PFOS yearly average at or above the MCL

compared the way EPA does: the average of a complete sampling set

lithium at or above EPA’s health reference level

lithium was part of the same survey

PFPeA was the compound Pennsylvania community systems found most often: 123 of 360 tested systems measured it above the reporting level. Across the country, 35% of surveyed community systems found at least one PFAS; in Pennsylvania the share is 45%. The largest Pennsylvania system with a detection, Philadelphia Water Department, serves 1,600,000 people and found 8 of the 29 compounds.

Which PFAS were found most often in Pennsylvania

Each row counts the Pennsylvania community water systems where that compound was measured above the reporting level at least once. A detection is a measurement, not a violation: most of these compounds have no federal limit.

Compound	Systems where found	Systems tested	Share
PFPeA	123	360	34%
PFBS	116	360	32%
PFHxA	110	360	31%
PFOA	96	360	27%
PFOS	90	360	25%
PFBA	83	360	23%
PFHxS	58	360	16%
PFHpA	46	360	13%
PFNA	21	360	6%
6:2 FTS	5	360	1%
PFUnA	3	360	1%
8:2 FTS	1	360	0%

Pennsylvania systems with the most PFAS found

The 10 surveyed community water systems that found the most different PFAS, with PFOA and PFOS compared to EPA’s 4.0 ppt limits on the yearly average at the highest sampling location. Larger systems come first when counts tie.

Water system	People served	PFAS found (of 29)	PFOA	PFOS
Emmaus Borough Public Water PA3390032	14,000	13	19.5 ppt at or above the MCL	127 ppt at or above the MCL
Ambler Boro Water Dept PA1460020	20,000	10	14.1 ppt at or above the MCL	12.5 ppt at or above the MCL
Doylestown Boro Water Dept PA1090081	8,700	10	14.0 ppt at or above the MCL	11.3 ppt at or above the MCL
Aqua Pa Main System PA1460073	822,600	9	11.8 ppt at or above the MCL	8.9 ppt at or above the MCL
North Wales Water Authority PA1460048	72,496	9	12.2 ppt at or above the MCL	11.0 ppt at or above the MCL
Northampton Bucks Co Mun Auth PA1090089	36,750	9	19.5 ppt at or above the MCL	22.2 ppt at or above the MCL
Muhlenberg TWP Muni Auth PA3060038	22,400	9	8.6 ppt at or above the MCL	10.9 ppt at or above the MCL
Pa American Audubon PA1460055	8,200	9	29.0 ppt at or above the MCL	54.1 ppt at or above the MCL
Aqua Pa Spring Run PA1150089	8,151	9	6.4 ppt at or above the MCL	2.2 ppt below the MCL
Telford Borough Authority PA1460050	7,700	9	14.5 ppt at or above the MCL	14.0 ppt at or above the MCL

Counties with the most systems that found PFAS

Bucks County 22 of 23 surveyed systems
Lancaster County 18 of 19 surveyed systems
Montgomery County 15 of 15 surveyed systems
Berks County 12 of 19 surveyed systems
Chester County 11 of 11 surveyed systems
York County 9 of 12 surveyed systems
Lehigh County 9 of 10 surveyed systems
Allegheny County 7 of 26 surveyed systems

How to read these numbers

UCMR 5 asked every community and non-transient non-community water system serving 3,300 or more people, and a sample of smaller ones, to test for 29 PFAS and lithium. EPA published the final data in August 2026; its samples were collected from January 2023 to June 2026. A system that was not in the survey has no result here; that is not the same as having no PFAS.

UCMR 5 is a one-time national monitoring survey. Its results do not indicate compliance or non-compliance with the PFAS Maximum Contaminant Levels, which are enforced on running annual averages and take effect in 2029 (EPA has proposed allowing extensions to 2031). A single result above a limit on this page is a measurement, not a violation.

See how to read UCMR 5 results and our methodology for how systems are matched to places.

After Pennsylvania’s PFAS results

Find your system. Then read its report.

State recordsAll Pennsylvania water recordsCounties, ZIP reports, lead results and violations for the whole state.FiltersChoosing a PFAS filterHow to check a filter’s certified PFAS reduction before you buy.Your utilityFind your annual water reportYour utility’s Consumer Confidence Report will list its own PFAS results and any treatment plans.

County pages

Pennsylvania water records

Sources

EPA UCMR 5 occurrence data, samples collected 2023-01-03 – 2026-06-17, final release, August 2026 (file dated Aug 28, 2026); EPA SDWIS via ECHO, 2026Q2 extract (file dated Jul 9, 2026); EPA service-area boundaries v3.0; Census 2020 ZCTAs. Database prepared 2026-09-03.