NEW YORK (CBSNewYork/AP) — Thousands of people in Westchester County lost water service for a few hours Wednesday, when New York City workers closed a major valve without notifying the affected communities.

Officials in Yonkers and Mount Vernon initially thought a water main had burst because of the sudden sudden drop in water pressure Wednesday.

The Mount Vernon water commissioner said a 48-inch shaft had been closed off.

Mount Vernon, Yonkers and other communities should have been notified about the valve maintenance so they could switch to backup water delivery systems.

But the New York City Department of Environmental Protection, which operates the watershed, said its workers notified a different set of municipalities, not the ones that would actually be affected.

Homes and businesses were affected in parts of Mount Vernon, Yonkers, Larchmont, Mamaroneck and Rye.

The DEP apologized.

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