A key reservoir that contributes to Pacific Palisades’ water supply was out of commission at the time the fires broke out, officials said Friday, and that closure may have contributed to firefighters losing water so early in the battle against the blaze.

Located within the Palisades, Santa Ynez Reservoir can hold millions of gallons of water. Records show maintenance work was recently performed on the reservoir cover.

Ellen Cheng, a spokeswoman for the Los Angeles Department of Water and Power, said in a statement Friday that the reservoir was out of service when the fires began.

“We are still evaluating what role it would have played in this situation if Santa Ynez had been offline,” she said.

The Pacific Palisades’ water supply comes from a 36-inch faucet pipe that flows by gravity from the larger Stone Canyon Reservoir, said Marty Adams, former general manager and chief engineer of the Los Angeles Department of Water and Power. This waterline also fills the Santa Ynez Reservoir.

The water from the two reservoirs then supplies the water system for the Pacific Palisades and also pumps systems that fill storage tanks that serve higher elevation homes in the neighborhood. It was unclear whether officials could have brought the reservoir back online before the fire after forecasters began warning of dangerous wildfires.

Officials said storage tanks in the Pacific Palisades area, which hold about 1 million gallons each, were full before the fire but then became depleted because so many firefighters were connecting to the system at the same time. The system had difficulty refilling the tanks in part because so much water was being taken from the main water line before it could get to the pumps that feed the higher tanks.

Mr Adams said a functioning reservoir would initially have been helpful in better supplying the water system in the area. But he also said it appeared the reservoir and tanks had been emptied at some point in a fire that destroyed so many homes at once. Municipal water systems are generally designed to maintain water loads during much smaller fires than Pacific Palisades used.

Years ago, crews had installed a cover for Santa Ynez Reservoir. Mr Adams said he had heard the cover was damaged and November contract documents indicated a company had been hired to repair the cover.

Mr Adams said repairs and maintenance of such systems were normal, as was shutdown of the reservoirs. Under normal circumstances, the water system in the area would have continued to function properly.

Janisse Quiñones, executive director and chief engineer of the city’s water department, said fighting the fire was placing an enormous strain on the system, four times the normal demand over a 15-hour period.

Los Angeles City Council member Traci Park, whose district includes Pacific Palisades, was not informed that the reservoir was decommissioned, a spokesman said Friday.

The spokesman, Pete Brown, said Ms. Park and her team had many questions about the water systems and Santa Ynez Reservoir and were seeking further answers about whether it should have been shut down.