334 public water systems in New York were sampled in EPA's UCMR 5 programme (2023–2025); we show six PFAS and lithium. Read 2026-10-31.
52 of 334 systems had at least one sample above a 2024 federal limit; 102 had at least one PFAS found above the reporting level; 232 had none found above the reporting level.
A single sample above a 2024 limit is a measurement, not a violation. Compliance is judged on running yearly averages, and water systems have until 2029 to meet the limits. On 20 May 2026 EPA proposed giving qualifying systems until 2031 for PFOA and PFOS and removing the limits for PFHxS, PFNA and HFPO-DA; those proposals were not final when we last checked (5 Nov 2026). Counts are per system, not per person; population figures are available only for systems serving more than 25,000 people (about 14,965,949 people across those systems here). UCMR 5 was a one-time national monitoring programme (2023–2025). The results are a snapshot at the system's entry points or taps on the sample dates, not a continuous measurement and not a compliance record.
| System | People served | UCMR 5 result |
|---|---|---|
| New York City System New York City System | 8,271,000 | None detected (below the reporting level) |
| Suffolk County Water Authority Suffolk County Water Authority | 1,100,000 | Above the 2024 limit in at least one sample |
| Monroe County Water Authority Mcwa | 525,262 | None detected (below the reporting level) |
| Onondaga County Water Authority Ocwa | 350,000 | None detected (below the reporting level) |
Pages for these are being added in stages. The data for all 334 systems is in the public dataset.
| System | People served | UCMR 5 result |
|---|---|---|
| Ecwa Direct Ecwa Direct | 313,380 | None detected (below the reporting level) |
| Buffalo Water Authority Buffalo Water Authority | 276,000 | None detected (below the reporting level) |
| Veolia Water Ny Veolia Water Ny | 270,000 | Above the 2024 limit in at least one sample |
| New York American Water - Lynbrook New York American Water - Lynbrook | 220,000 | Above the 2024 limit in at least one sample |
| Yonkers City Yonkers City | 211,569 | None detected (below the reporting level) |
| Rochester City Rochester City | 210,000 | None detected (below the reporting level) |
| Syracuse City Syracuse City | 192,000 | None detected (below the reporting level) |
| Suez Water Westchester, Inc. Rd-1 Suez Water Westchester, Inc. Rd-1 | 146,732 | None detected (below the reporting level) |
| New York American Water - Merrick New York American Water - Merrick | 135,000 | None detected (below the reporting level) |
| Mvwa - Mohawk Valley Water Authority Mvwa - Mohawk Valley Water Authority | 126,250 | None detected (below the reporting level) |
| Wa of Western Nassau Wa of Western Nassau | 120,000 | Above the 2024 limit in at least one sample |
| Town of Hempstead Water Department Town of Hempstead Water Department | 110,000 | None detected (below the reporting level) |
| Albany City Albany City | 98,000 | None detected (below the reporting level) |
| Latham Water District Latham Water District | 85,590 | None detected (below the reporting level) |
| South Huntington Water District South Huntington Water District | 81,760 | None detected (below the reporting level) |
| Mount Vernon Water Department Mount Vernon Water Department | 73,893 | None detected (below the reporting level) |
| Tonawanda, Town Water Dept. Tonawanda, Town Water Dept. | 72,571 | None detected (below the reporting level) |
| Schenectady City Water Works Schenectady City Water Works | 62,000 | None detected (below the reporting level) |
| Westchester Joint Water Works Westchester Joint Water Works | 59,629 | None detected (below the reporting level) |
| White Plains City White Plains City | 59,559 | None detected (below the reporting level) |
| Jericho Wd Jericho Wd | 58,000 | None detected (below the reporting level) |
| Suez Water Westchester, Inc. Rd2 Suez Water Westchester, Inc. Rd2 | 57,301 | Above the 2024 limit in at least one sample |
| Hempstead (V) Hempstead (V) | 56,000 | Above the 2024 limit in at least one sample |
| Elmira Water Board Elmira Water Board | 54,000 | None detected (below the reporting level) |
| Palm Tree Palm Tree | 51,623 | None detected (below the reporting level) |