NYACK, NY (AP / CBSNewYork) – About 15,000 customers in several suburban New York communities are being advised to boil their water due to the presence of high levels of coliform bacteria.

The Rockland County Department of Health issued the order for Nyack Water Department customers on Tuesday.

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Coliform bacteria are commonly found in water supplies but elevated levels are an indicator that potentially harmful microbes may exist. Symptoms include diarrhea, cramps, nausea and headaches.

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Health Commissioner Joan Facelle tells the Journal News tests didn’t show the presence of the much more dangerous E. coli or fecal bacteria.

Nyack Water Department Superintendent Harry Williams says the source of the contamination is being investigated. The order is expected to last 3-5 days for customers in Nyack, South Nyack, Central Nyack and a portion of West Nyack.

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The Palisades Center mall and Nyack Hospital are included in the boil water order.

On Main Street in Nyack, many businesses had switched to bottled water on Wednesday, but some still used the tap for the morning coffee.

Nyack Mayor Rich Kavesh is working to spread the word.

“My phone’s been ringing off the hook. My e-mail’s been packed with messages from people who never received the 911 reverse call. So, I’ve asked the county to redo that entire phone calling operation,” he told WCBS 880 reporter Sean Adams.

The source of the contamination has not been found.

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