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.

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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.

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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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