June 26. 2013 12:39PM

Large sink hole strands motorist in Manchester neighborhood

New Hampshire Union Leader

A sinkhole opened at the intersection of Morning Glory and Stonington drives in Manchester Wednesday. A Water Works official said a ruptured water line may have washed away the sand and gravel supporting the roadway. (DAVID LANE/UNION LEADER)

MANCHESTER — The city cut off water to more than a dozen homes this morning, after a sink hole in an upscale south Manchester subdivision opened up and stranded an automobile in the early morning hours.

Manchester Water Works officials said they hope to restore water to homes along Stonington Drive and Morning Glory Drive by 5 p.m. But they cautioned they are unsure of the extent that Morning Glory Drive has been undermined.

Three other sink holes developed on a steep portion of the roadway, signaling the likelihood of further undermining of pavement.

"It's like an earthquake," said Nancy Washburn, who lives at the corner of Stonington and Morning Glory. The streets are part of the Rosecliff subdivision.

A portion of the road was closed to through traffic, and workers were using heavy equipment to dig a hole deep enough to reach a damaged valve to a water main. As of noon, it was unclear how much Morning Glory Drive had been undermined.

"Depending on how bad it was, it will either be a trench or the width of the road," said Guy Chabot, Manchester Water Works deputy director of distribution. "We're going to have to keep poking around there until we find out where the voids are."

Water Works was notified of the problem before 6 a.m., when a car hit the sink hole, stranding the front end of the vehicle.

Arthur Washburn said he woke to see a tow truck removing the car, which was able to drive off. He said water had pooled in the sink hole, but was not gushing.

Workers at the site said the initial hole was about 12-by-10 feet in diameter and 3 1/2 feet deep.

It appears that the isolation valve on an 8-inch water line blew, Chabot said. Such as rupture sends high-pressure water streaming into the sand and gravel that holds up roadways, washing the material away.

"It's entirely possible erosion had something to do with it," Chabot said.