Westchester County office water: PFOA is non-detect on the NYC Catskill and Delaware supply and 6 ppt in Peekskill. Your system decides.

By the standards that regulate it, yes: every system on this page met its enforceable limits in the 2024 reporting round. What the reports also show is that the water is not the same building to building. Four of the five systems here buy water from New York City’s Catskill and Delaware reservoirs; Peekskill treats its own reservoir supply, and its numbers read differently.^[1]

The spread is the story. PFOA is reported as non-detect in Yonkers, White Plains, the Veolia Westchester district, and Westchester Joint Water Works, while Peekskill reports 6 ppt, all in the same county, all in the same reporting year.^[5][1] A countywide statement cannot describe your office; the system feeding your address can.

And even the right system report stops at the property line. What reaches your breakroom also depends on the building’s own plumbing, which no utility report measures: Yonkers itself reports individual homes up to 11.3 ppb of lead even with a fully compliant 90th percentile.^[5] The only number that settles it for an office is one measured at your tap.

In most of the county’s large systems, no: PFOA and PFOS came back non-detect in the 2024 reports for Yonkers, White Plains, the Veolia Westchester district, and Westchester Joint Water Works, because the protected Catskill and Delaware supply has consistently tested clean.^[5][4] In Peekskill, yes: the city’s report shows PFOA at 6 ppt (samples 4.6 to 6.0) and PFOS at 4.3 ppt, both above the 4 ppt federal MCLs finalized in April 2024, which systems must meet by 2029.^[1][6]

Neither Peekskill reading is a violation: the federal deadline is not yet in force, and both values sit below New York’s current 10 ppt state limits, which the city’s own report cites.^[1] What the numbers mean for an office on that supply is simpler: point-of-use filtration is how it gets real margin below the strictest number on the utility’s own report, today.

Because compliance is graded on averages, and single samples show what can actually arrive at a tap. Three county specifics make the case:

• Disinfection byproducts can spike well past the federal limit at the tap. In the Veolia Westchester district, a single 2024 sample measured haloacetic acids (HAA5) at 80.8 ppb, above the 60 ppb federal MCL threshold; the system remained in compliance because compliance is calculated as a locational running annual average, which was 52 ppb.^[2][7] The average is what the rule grades; the spike is what a tap can pour.
• The Harrison and Mamaroneck corridor runs on unfiltered surface water. Westchester Joint Water Works disinfects with UV and chlorine but does not yet filter; its federally directed Rye Lake filtration plant is due in 2029. Its 2024 report shows a single October nitrate sample at 11.6 mg/L against the 10 mg/L federal MCL (confirmation-sample averaging kept the system compliant, and no violation was issued) and an HAA5 reading of 52 ppb, 87 percent of the federal limit.^[3][8][7]
• Even the strong reports carry numbers worth watching. White Plains reports its highest HAA5 running annual average at 48.5 ppb, 81 percent of the 60 ppb federal limit, and Yonkers reports lead at a 7.14 ppb 90th percentile with individual homes as high as 11.3 ppb, under the 15 ppb action level.^[4][5][9] Building plumbing adds the last variable no city report captures.