A water main burst and flooded the roads of Boston's Beacon Hill neighborhood overnight.
The break, near Myrtle, Derne and Hancock streets, sent water rushing through Hancock Street to Cambridge Street. Some roads were closed Tuesday morning.
Water got into some of the homes, but fire officials said the damage wasn't as bad as expected. Some people were moved to higher ground but no evacuations were needed, Deputy fire Chief James Greene said.
"They went unit to unit, checked to make sure that the occupants were safe," Greene said. "There is some water in some of these units -- not as much as you would think, based on the amount of water coming down the road, but still enough to cause a problem."
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Hancock Street was closed between Myrtle and Cambridge streets, while Myrtle Street was shut down to Joy Street for some time Tuesday morning.
Work was already being done in the area to replace pipes.
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"A contractor working for Boston Water and Sewer at the intersection of Hancock and Dern, it looks like there was a valve adjacent to their work that let go -- a 30-inch main -- let go of a substantial amount of water," Greene said.
Officials later confirmed that the line being replaced was a 12-inch and not a 30-inch main. The gate valve for the main reportedly let go, resulting in the flooding.
The water valve was shut off by about 2:30 a.m., the Boston Fire Department wrote on Twitter. As of noon, only about 50 customers were still without water on Myrtle Street.
Firefighters checked the units up and down Beacon Hill to make sure everyone was safe, and that the buildings were structurally sound. The Inspectional Services Department of Boston, electrical and plumbing were investigating any water damage to the buildings.
The Boston Water and Sewer Commission was working to fix the main and Boston Public Works was assessing damage to the streets. Utility companies Eversource and National Grid were on scene by around 3:45 a.m.
"We're not exactly sure what happened," said Tom Bagley, a spokesman for the agency, said Tuesday morning.
Initially, the water commission said the contractor -- the D’Alessandro Corporation -- damaged the valve. But the company said it followed all the proper procedures and a valve failed on a nearby 30-inch, which they had reminded the city to shut off as required.
Cleanup continued through the day. As of around 10 p.m., water services had been restored.