Capt. Jaime Moore of the L.A. City Fire Department said the gas leak was not dangerous.
Moore said workers with the Department of Water and Power were trying to lift the asphalt when they punched a hole in an unidentified three-inch gas main in the 6800 block of N. Coldwater Canyon Avenue at about 10 a.m.
The leak was under control, but it took officials a few hours to identify the source of the gas to shut it down.
Local businesses near the intersection of Coldwater Canyon Avenue and Vanowen Street were evacuated as a precaution.
Streets were reopened just after 2 p.m. after the gas line was repaired. No injuries have been reported.