PFAS in tap water, Hempstead town/township, New York
1 of 6 water systems had PFAS-4 above our 0.5 ng/L benchmark at the latest sample. Highest: Liberty Utilities New York - Lynbrook, 15.5 ng/L. 2 had PFOA or PFOS above the 4 ng/L federal MCL in at least one sample.
Hempstead town/township is served by 6 community water systems · 637,031 people served
Water systems serving Hempstead town/township
| Water system | People served | PFAS-4 at the latest sample | Entry points | Latest sample |
|---|---|---|---|---|
| Liberty Utilities New York - Lynbrook | 220,000 | 15.5 ng/L above the 2029 federal MCL | 18 | August 13, 2025 |
| Liberty Utilities New York - Merrick | 135,000 | below the 3 to 4 ng/L reporting limit | 8 | July 10, 2025 |
| WA of Western Nassau | 120,000 | below the 3 to 4 ng/L reporting limit above the 2029 federal MCL in an earlier sample | 13 | January 25, 2024 |
| Town of Hempstead Water Department | 110,000 | below the 3 to 4 ng/L reporting limit | 13 | December 18, 2024 |
| West Hempstead WD | 32,031 | below the 3 to 4 ng/L reporting limit | 2 | April 25, 2024 |
| Franklin Square WD | 20,000 | below the 3 to 4 ng/L reporting limit | 3 | October 8, 2024 |
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.
Census county subdivision "Hempstead town", matched from the city rows the systems report to SDWIS.
County
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.