A heavy construction vehicle punctured a high-pressure natural gas main in Palmdale on Wednesday morning, releasing a roaring flow of gas that forced the evacuation of more than 40 houses and slightly injured a worker.
Southern California Gas Co. workers using a heavy-duty hydraulic clamp closed off the six-inch distribution line shortly before 2 p.m., about six hours after the rupture near 10th Street West and Beechdale Drive.
About 20 evacuees were allowed back into their homes after the line was sealed.
Dave Lopez, a 37-year-old gas company worker, suffered a minor knee injury as a crew tried to clamp the line and the gushing gas blew a piece of equipment off the pipe, knocking Lopez down. He was treated and released at Palmdale Hospital.
At 12:15 p.m., workers abandoned attempts to use hand-held equipment to seal the line and instead reduced the flow of gas using underground valves. The later arrival of an emergency truck with the hydraulic clamp enabled officials to close off the leak without shutting off service to thousands of customers.
Officials planned to restore gas service Wednesday night to 40 homes where service has been cut, said Colleen Walker, a Southern California Gas Co. spokeswoman.
Residents were evacuated because the ruptured line, at a pressure more than 10 times greater than residential lines, posed the threat of a fire if ignited.
But county Fire Department officials said the danger was minimal, because a strong breeze dissipated the fumes away from buildings into an open desert area.
A road crew with Burhoe Construction broke the pipe, a main supply line for the Antelope Valley, while working on a city contract to widen 10th Street West in preparation for a nearby regional mall, according to Palmdale Public Works Director Steve Williams.
Walker, of the gas company, said construction contractors are required to know the location of gas lines in areas where they are working.
“I think it was a mistake in digging,” she said.