Pacific Coast Highway was closed at Carbon Canyon Road in Malibu on Thursday after construction workers accidentally ruptured a gas line under the road, officials said.
Emergency officials evacuated about 30 residences and 20 business that were within 1500 feet of the break, Los Angeles Sheriff's Lt. Todd Weber told NBC4.
The road initially was closed in both directions. At 11:50 a.m., the sheriff's department said both eastbound lanes and one westbound lane had reopened.
"Once the gas is off and they can let the gas dissipate, they'll re-open PCH," Weber said.
People who live in the area and need someplace to wait out the evacuation can go to Malibu City Hall, he said.
The incident occurred at about 9:45 a.m. The construction was part of a project by Malibu's public works department, he said.
There was no fire or explosion, and no one was injured, he said.