The Westchester County Health Department says tests show the water used in Sleepy Hollow, Tarrytown, Elmsford, Hawthorne, Valhalla and Thornwood is now safe for consumption.
Residents had been warned to boil their water before drinking it or cooking with it because high levels of sediment had appeared in water from the Catskill Aqueduct. Sediment interferes with water purification.
The Health Department said the sediment was probably stirred up by recent precipitation, including several snowstorms.
A boil-water advisory for Ramapo and New City in Rockland County, prompted by a broken water pipe, was lifted earlier this week.