PFAS in tap water, Franklin County, Pennsylvania
None of the 7 water systems had a PFAS-4 compound above the 3 to 4 ng/L reporting limits at the latest sample. That's below the lab limit, not zero.
7 community water systems · 101,006 people served · newest sample February 2, 2026
Water systems in Franklin County
| Water system | People served | PFAS-4 at the latest sample | Entry points | Latest sample |
|---|---|---|---|---|
| Chambersburg Boro Water Sys | 31,048 | below the 3 to 4 ng/L reporting limit | 1 | June 3, 2025 |
| Guilford Water Auth | 28,135 | below the 3 to 4 ng/L reporting limit | 3 | October 12, 2023 |
| Boro of Waynesboro | 13,200 | below the 3 to 4 ng/L reporting limit | 2 | August 6, 2025 |
| Bear Valley Joint Auth | 12,589 | below the 3 to 4 ng/L reporting limit | 2 | March 10, 2025 |
| Washington TWP Muni Auth | 6,134 | below the 3 to 4 ng/L reporting limit | 5 | July 16, 2024 |
| Greencastle Area Water Auth | 5,500 | below the 3 to 4 ng/L reporting limit | 1 | November 19, 2024 |
| Franklin System York Water | 4,400 | below the 3 to 4 ng/L reporting limit | 1 | February 2, 2026 |
| Fannett Metal Sch Dist non-transient non-community water system | 600 | monitored under UCMR 5, no page | ||
1 system without a page is not a community water system (schools, workplaces, campgrounds). Nobody's home tap water.
Not sure which one is yours? The systems report their own service areas to EPA. Check your water bill or your utility's Consumer Confidence Report.
ZIP codes in Franklin County
Census ZIP code tabulation areas that overlap the county. A ZIP served by one system opens that system's page; a ZIP shared by several systems lists them.
How to read these numbers
We compare PFAS-4 (PFOA + PFOS + PFNA + PFHxS) with this site's 0.5 ng/L benchmark, the same line as on the European pages. UCMR 5 reporting limits are 3 to 4 ng/L. So any quantified PFAS-4 compound is above the benchmark, and a clean result reads "below the 3 to 4 ng/L reporting limit", never zero. The US legal limit is the 4 ng/L federal MCL for PFOA and PFOS, which systems must meet from April 26, 2029 ("above the 2029 federal MCL").
EPA: "UCMR 5 results do not indicate compliance or noncompliance with the PFAS drinking water standards". Samples are taken where water enters the distribution system, not at your tap. A system may have changed sources or added treatment since. Source: U.S. Environmental Protection Agency (EPA), Office of Water, PFAS National Primary Drinking Water Regulation (NPDWR). Regulation details retrieved September 19, 2026. Every system page tracks the 2029 compliance date and the proposed rescission of the PFHxS, PFNA, HFPO-DA and Hazard Index limits.
This site is a data project, not an official source. If in doubt, check with your water supplier or local authority.