Public Work crews had to repair Dover's fourth water main break of the day Wednesday night on Atkinson Street.

Repairs to the cast iron pipes which date back to the 1880s could take several hours to complete and water service was temporarily shut off. Water pressure in other areas of the city could be affected.

"We don’t have any unusual activity occurring with the water distribution system," Director of Community Services John Storer said in a statement. "This break is likely the result of a pressure anomaly that occurred during the overnight hours. The old cast iron pipe becomes very brittle and likely cracked."

The day's breaks began around 1:30 a.m. on Broadway. There were breaks later in the morning on Atkinson Street and Hough Street in the cast iron pipe which date back to the 1880s. Those pipes were all repaired and full water was restored.

The reasons for the earlier breaks are under investigation by Community Services. Storer and Deputy Director Bill Boulanger theorize that a "water hammer" may have developed by a pressure surge that finds weak spots. The surge could have been created when the water was shut off on Broadway.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNH

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