An estimated 3,000 homes and businesses on the Balboa Peninsula were still without gas Friday afternoon because of a major pipeline rupture on the beach the day before.
It could take until Sunday to restore service to all those customers , according to a Southern California Gas Co. representative.
Newport Beach officials said contractors caused the rupture while working to replenish sand near 20th Street.
Sand was trucked to the area after being excavated from the city's Marina Park project on the peninsula, and two frontloaders were spreading it near the Newport Pier, said Public Works Director Dave Webb.
However, it is unclear why heavy equipment working on the beach's surface would break a pipe under the sand.
"I don't absolutely understand how they hit it or why they hit it," Webb said.
He speculated there could have been a low spot that needed filling in or perhaps the pipe wasn't buried deeply enough.
The breach caused evacuations of nearby homes Thursday until workers were able to shut down the leak at about 2:45 a.m. Friday by cutting off natural gas to everyone south of 23rd Street.
Firefighters escorted displaced residents back to their homes around 3 a.m., police said.
Crews were working to repair the pipe, and that should by done by Friday night, Javier Mendoza, a spokesman for the gas company, said in an email.
After that, crews must go door to door to inspect and reset meters at each home and business before the location's gas is turned back on.
That process could stretch through the weekend and requires someone to be present to give workers access to the gas meter.
"If customers are not at home when we come by, we will leave a door hanger with a contact number so they can call us to complete the service restoration," Mendoza said.
Residents who have questions can visit an information booth set up at 20th Street and Oceanfront or call (800) 427-2200.