PFAS in tap water, Warren County, New Jersey

3 of 6 water systems had PFAS-4 above our 0.5 ng/L benchmark at the latest sample. Highest: NJ American Water - Short Hills, 14.7 ng/L. 2 had PFOA or PFOS above the 4 ng/L federal MCL in at least one sample.

6 community water systems · 282,143 people served · newest sample October 15, 2025

Water systems in Warren County

Water system People served PFAS-4 at the latest sample Entry points Latest sample
NJ American Water - Short Hills 217,230 14.7 ng/L above the 2029 federal MCL 12 August 12, 2024
Aqua NJ - Phillipsburg 26,686 below the 3 to 4 ng/L reporting limit 1 October 9, 2024
Hackettstown MUA 22,000 below the 3 to 4 ng/L reporting limit 4 December 3, 2024
NJ American Water - Washington/Oxford 10,719 11.7 ng/L above the 2029 federal MCL 6 August 8, 2025
Allamuchy TWP Water & Sewer 5,423 3.3 ng/L 1 October 6, 2025
Riverside MHP 85 below the 3 to 4 ng/L reporting limit 1 October 15, 2025

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.

Cities and towns

ZIP codes in Warren 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.