PFAS in the drinking water of Caernarvon TWP Auth: 47.8 ng/L, 95.6x our 0.5 ng/L benchmark
Last PFAS check: · Source: EPA UCMR 5
PFAS in drinking water
95.6× above our health benchmark
0.5 ng/L is our benchmark, not an official limit. It uses the same EFSA method as the Swedish, Danish and Dutch limits, with stricter safety choices. It's meant as a yearly average. The comparison above uses the latest check.
checked on October 20, 2025
Sampled on October 20, 2025 at Entry Point - Mill Road (MILL ROAD). It has the highest PFAS-4 sum of the system's 3 entry points. Samples are taken at the entry point to the distribution system, not at your tap.
US legal limit: 4.0 ng/L federal MCL for PFOA and PFOS
- PFOA 47.8 ng/L above the 2029 federal MCL above the Pennsylvania MCL of 14 ng/L
- PFOS below the 4 ng/L reporting limit below the federal MCL
Applies from April 2029, as a running annual average per sampling point. UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards.
Other regulated PFAS: 10 ng/L MCLs and the Hazard Index. PFHxS below the 3 ng/L reporting limit, PFNA below the 4 ng/L reporting limit, HFPO-DA below the 5 ng/L reporting limit; Hazard Index (PFHxS, PFNA, HFPO-DA, PFBS): 0.01 (limit 1). EPA proposed on May 20, 2026 to rescind the PFHxS, PFNA, HFPO-DA MCLs and the Hazard Index; no final rule had been published when this page's regulation data was retrieved (September 19, 2026).
More about this result
Substances below the detection limit count as 0, so the real total may be higher.
One of these four, PFOA, is classified as causing cancer in humans by the WHO's cancer research agency (IARC).
More PFAS than in 99% of the water systems we track
UCMR 5 measures 29 PFAS one by one and publishes no EU-style total; this page shows the PFAS-4 sum and each compound.
29 PFAS (see each substance)
| PFAS substance | Value |
|---|---|
| PFHxA | 70.5 ng/L |
| PFPeA | 55 ng/L |
| PFOA | 47.8 ng/L |
| PFBA | 42.5 ng/L |
| PFBS | 25.6 ng/L |
| PFHpA | 18.5 ng/L |
| PFOS | below the 4 ng/L reporting limit |
| PFHxS | below the 3 ng/L reporting limit |
| PFNA | below the 4 ng/L reporting limit |
| HFPO-DA | below the 5 ng/L reporting limit |
| 11Cl-PF3OUdS | below the 5 ng/L reporting limit |
| 4:2 FTS | below the 3 ng/L reporting limit |
| 6:2 FTS | below the 5 ng/L reporting limit |
| 8:2 FTS | below the 5 ng/L reporting limit |
| 9Cl-PF3ONS | below the 2 ng/L reporting limit |
| ADONA | below the 3 ng/L reporting limit |
| NEtFOSAA | below the 5 ng/L reporting limit |
| NFDHA | below the 20 ng/L reporting limit |
| NMeFOSAA | below the 6 ng/L reporting limit |
| PFDA | below the 3 ng/L reporting limit |
| PFDoA | below the 3 ng/L reporting limit |
| PFEESA | below the 3 ng/L reporting limit |
| PFHpS | below the 3 ng/L reporting limit |
| PFMBA | below the 3 ng/L reporting limit |
| PFMPA | below the 4 ng/L reporting limit |
| PFPeS | below the 4 ng/L reporting limit |
| PFTA | below the 8 ng/L reporting limit |
| PFTrDA | below the 7 ng/L reporting limit |
| PFUnA | below the 2 ng/L reporting limit |
Above our health benchmark. You can compare filter types below.
- Federal MCL, PFOA and PFOS (each)
- 4.0 ng/L PFOA above it at the headline sample; applies from April 2029
- Latest UCMR 5 sample
- October 20, 2025 entry-point sample, not your tap
- EPA system ID (PWSID)
- PA3060052
Details and sources
At Caernarvon TWP Auth (Pennsylvania), the four most closely watched PFAS (PFAS-4) add up to at least 47.8 ng/L (0.0478 µg/L), the other compounds being below the 3 to 4 ng/L reporting limit in the latest UCMR 5 entry-point sample on October 20, 2025 at Entry Point - Mill Road (MILL ROAD). That is 95.6 times the 0.5 ng/L health benchmark used by pfasnearme. PFOA 47.8 ng/L and PFOS below the 4 ng/L reporting limit, PFOA above the 4.0 ng/L federal MCL for PFOA and PFOS that systems must meet from April 2029. Across 6 UCMR 5 sampling events since April 14, 2025, the PFAS-4 sum reached up to 55.8 ng/L and was below the reporting limits at other times. Source: U.S. Environmental Protection Agency, Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) occurrence data, final dataset (August 2026), public domain.
PFAS over time in Caernarvon TWP Auth
6 UCMR 5 sampling events since April 14, 2025, as published by EPA. Samples come from 3 entry points; the trend refers to Entry Point - Mill Road (MILL ROAD).
| Date | PFAS-4 | Entry point |
|---|---|---|
| 47.8 ng/L | Entry Point - Mill Road (MILL ROAD) | |
| < 15 ng/L | Entry Point - Well 8 MBP (WELL #8 MBP) | |
| < 15 ng/L | Entry Point - Well 7 (WELL 7 HEMLOCK RD) | |
| 55.8 ng/L | Entry Point - Mill Road (MILL ROAD) | |
| < 15 ng/L | Entry Point - Well 8 MBP (WELL #8 MBP) | |
| < 15 ng/L | Entry Point - Well 7 (WELL 7 HEMLOCK RD) |
A value preceded by "<" means no PFAS-4 compound was quantified, the figure being the sum of the four UCMR 5 reporting limits. Sums with a compound below the 3 to 4 ng/L reporting limit are lower bounds. How to read a PFAS result
Compliance status
UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards. UCMR 5 is a national monitoring survey; the system's compliance record and its annual Consumer Confidence Report come from the state agency and EPA's SDWIS.
See all 4 test results
| What was tested | Value | Limit | Status |
|---|---|---|---|
| PFAS Hazard Index (US EPA) | 0.01 (index) | MCL (from April 2029): 1 | within the Hazard Index limit |
| PFAS-4 (PFOA + PFOS + PFNA + PFHxS) · Entry Point - Well 8 MBP (WELL #8 MBP) · maximum | below the 15 ng/L reporting limit | no MCL for the sum; MCL (from April 2029) 4.0 ng/L for PFOA and for PFOS | not detected |
| PFAS-4 (PFOA + PFOS + PFNA + PFHxS) · Entry Point - Well 7 (WELL 7 HEMLOCK RD) · maximum | below the 15 ng/L reporting limit | no MCL for the sum; MCL (from April 2029) 4.0 ng/L for PFOA and for PFOS | not detected |
| Lithium · UCMR 5, for reference | below the 9 µg/L reporting limit | no MCL | for reference |
Frequently asked questions
Is the tap water in Caernarvon TWP Auth safe to drink?
In the latest UCMR 5 entry-point sample on October 20, 2025, the four most closely watched PFAS added up to at least 47.8 ng/L, 95.6 times the 0.5 ng/L health benchmark pfasnearme uses. PFOA was above the 4.0 ng/L federal MCL that systems must meet from April 2029. EPA set the maximum contaminant level goal (MCLG) for PFOA and PFOS at zero because there is no level without risk. UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards, and this site reports published measurements without judging health risk. This is not medical advice. If you are concerned, talk to your water system or your doctor.
What is UCMR 5 and why do the results say "below the reporting limit"?
The Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) had every large US water system and a sample of small ones test 29 PFAS and lithium between 2023 and 2025, at each entry point to the distribution system. EPA set minimum reporting levels of 3 to 4 ng/L for PFOA, PFOS, PFNA and PFHxS and reports nothing below them. A result "below the 3 to 4 ng/L reporting limit" therefore means the lab could not quantify the compound, not that it is absent, and it is never shown here as zero.
What do the 0.5 ng/L benchmark and the 4.0 ng/L MCL mean, and why are both shown?
0.5 ng/L for the PFAS-4 sum (PFOA + PFOS + PFNA + PFHxS) is the health benchmark pfasnearme applies on every page, in Europe and the United States, built from the European Food Safety Authority's tolerable intake with stricter safety choices. 4.0 ng/L is the enforceable federal maximum contaminant level for PFOA and for PFOS individually under EPA's PFAS National Primary Drinking Water Regulation (NPDWR), the US legal limit. Any PFAS-4 compound quantified under UCMR 5 (at or above 3 to 4 ng/L) is above the benchmark, so the benchmark tells you whether anything was found and the MCL tells you whether the system would have to act. EPA set the maximum contaminant level goal (MCLG) for PFOA and PFOS at zero because there is no level without risk.
When does the 4.0 ng/L MCL apply, and could it change?
EPA published the PFAS National Primary Drinking Water Regulation (NPDWR) on April 26, 2024. Systems must finish initial monitoring by April 26, 2027, tell customers about PFAS in their 2027 Consumer Confidence Reports, and comply with the PFOA and PFOS MCLs from April 26, 2029. Two proposals published on May 20, 2026 are not final: one would let systems in states where EPA holds primacy extend PFOA and PFOS compliance to April 26, 2031; the other would rescind the PFHxS, PFNA, HFPO-DA MCLs and the Hazard Index while keeping PFOA and PFOS. The rule is also before the U.S. Court of Appeals for the D.C. Circuit (American Water Works Association v. EPA, argued 2026-09-18 before Judges Millett, Pillard and Wilkins; no decision). Regulation data retrieved September 19, 2026.
Does Pennsylvania have its own PFAS limits?
Yes. Pennsylvania Department of Environmental Protection (PA DEP), Bureau of Safe Drinking Water enforces MCLs under 25 Pa. Code Chapter 109 (PFAS MCL Rule): PFOA 14 ng/L (since January 14, 2023); PFOS 18 ng/L (since January 14, 2023). The federal PFOA and PFOS MCLs (4.0 ng/L) are stricter than every state MCL, so the federal line is about severity and the state line is about what is enforceable today. In this UCMR 5 sample, PFOA was above the Pennsylvania MCL. State monitoring: initial monitoring 2024, quarterly compliance monitoring since 2024; statewide results summary xlsx refreshed semi-annually.
Is this the water that comes out of my tap in Caernarvon TWP Auth?
Only if Caernarvon TWP Auth (PWSID PA3060052) is your water system: check your water bill or your ZIP code page on this site, or the Berks County page. Samples are taken at the entry point to the distribution system, not at your tap. The system may have changed sources or installed treatment since this sample. PFAS treatment reported to EPA: not reported to EPA. The system's own Consumer Confidence Report, published every year, states what it measures today.
What can I do about PFAS in my water?
Ask Caernarvon TWP Auth for its latest PFAS results and its plan for the 2029 MCLs, read its Consumer Confidence Report (EPA's CCR finder, PWSID PA3060052), and if you want to lower PFAS at home, use a filter certified to NSF/ANSI 53 or 58 for PFOA and PFOS (reverse osmosis and activated carbon block filters; see the filter comparison linked on this page). Boiling water does not remove PFAS.
Are PFAS levels rising in Caernarvon TWP Auth's water?
pfasnearme reads a trend per entry point, and the headline entry point (Entry Point - Mill Road (MILL ROAD)) has 2 quantified samples across the 6 UCMR 5 sampling events since April 14, 2025; a trend needs at least three. UCMR 5 monitoring is complete, so later trends will come from state compliance monitoring.
Where does this data come from?
Source: U.S. Environmental Protection Agency, Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), final dataset August 2026, retrieved 2026-09-19. Public domain. Results are entry-point samples and do not indicate compliance with drinking water standards. System registry from EPA SDWIS/ECHO (2026Q2 edition); service areas from EPA ORD (model code MIT); geography from the U.S. Census Bureau. pfasnearme retrieved the data on September 19, 2026.
Water systems in the same county
Other community water systems in Berks County covered by this site, largest first.
Nearby water systems
The community water systems closest to Caernarvon TWP Auth covered by this site, by service-area center.
Data source
- U.S. Environmental Protection Agency, Fifth Unregulated Contaminant Monitoring Rule (UCMR 5) occurrence data, final dataset (August 2026)
- https://www.epa.gov/dwucmr/occurrence-data-unregulated-contaminant-monitoring-rule
- License
- Public domain (U.S. federal government work, 17 U.S.C. § 105)
- Retrieved
- September 19, 2026
- Entry points and samples
- Entry Point - Mill Road (MILL ROAD), Entry Point - Well 8 MBP (WELL #8 MBP), Entry Point - Well 7 (WELL 7 HEMLOCK RD)
- UCMR 5 sample window
- April 14, 2025 to October 20, 2025; 3 entry points, 6 sampling events
- Source water
- groundwater; community water system (small, 10,000 people or fewer)
- PFAS treatment reported to EPA
- not reported to EPA. The system may have changed sources or installed treatment since this sample.
- Consumer Confidence Report
- Search EPA's CCR finder for PWSID PA3060052 to read the system's own annual report
- Regulation data (MCLs, dates) retrieved
- September 19, 2026
Source: U.S. Environmental Protection Agency, Fifth Unregulated Contaminant Monitoring Rule (UCMR 5), final dataset August 2026, retrieved 2026-09-19. Public domain. Results are entry-point samples and do not indicate compliance with drinking water standards.
System registry from EPA SDWIS/ECHO (2026Q2 edition); service areas from EPA ORD (model code MIT); geography from the U.S. Census Bureau.
UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards. Samples are taken at the entry point to the distribution system, not at the tap; the system may have changed sources or installed treatment since. 3 entry points sampled, 6 sampling events between 2025-04-14 and 2025-10-20. The page's PFAS values come from the newest sample at Entry Point - Mill Road (MILL ROAD) (101/EP101), the entry point with the highest PFOA + PFOS + PFNA + PFHxS sum; the other entry points' maxima are listed as separate rows. Non-detects are shown as "<" followed by EPA's minimum reporting level (3 to 20 ng/L); PFAS-4 sums quantified compounds only, so it is a lower bound when a compound was not detected. Registry (name, population, counties, ZIPs) from EPA SDWIS/ECHO; service-area centroid from EPA ORD.
Get notified when alerts open for Caernarvon TWP Auth
Email alerts for US water systems start once our US postal address is published (CAN-SPAM). We collect nothing here yet; the report for Caernarvon TWP Auth on this page is updated as new results are published.
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.