Southern California Gas Company says a water main leak caused water to enter a natural gas line on Tuesday. The water contaminated the gas system and the gas system contamined the water system.
The company was forced to shut off service to thousands in the Montclair area. The Monte Vista Water District stopped service to 23 of their customers.
Crews were able to repair the gas pipeline Friday, but must now go door-to-door to restore service to affected customers.
The service restoration process consists of purging the water from the system, replacing affected meters, relighting pilot lights and performing a safety check.
Water in the gas line causes meters and regulators to stop working so crews have the tedious job of replacing the meters and regulators, as well as extracting any remaining water from the system.
The water company is conducting quality testing, and then has to flush the plumbing of each of its affected customers.
SoCalGas said they hope to have service restored to everyone by the end of the weekend.
"SoCalGas crews will require access to homes and businesses that have lost service. This is a safety-focused process and SoCalGas crews will work over the next few days to get this done as quickly and safely as possible," SoCalGas said in a statement Friday.
Natural gas is non-toxic, and officials say none of the affected customers are in danger. The cause of this incident remains under investigation.
Some residents expressed their frustration about not having hot water.
"I am dealing with kids. It's hard. You have to wash their hair, cold water. [I'm] heating up water in a microwave. I have to go to work," said Montclair resident Mona Bradford.
Others are taking the outage in stride.
"You can holler and complain, but there is nothing you can do," said Montclair resident Clark Goodwin.
A command post was set up at the Costco store on the 9000 block of Central Avenue in Montclair.