A reservoir in the Palisades that holds 117 million gallons of water was offline this month for previously scheduled maintenance. It was empty when the Palisades fire exploded

A major reservoir in Pacific Palisades, integral to Los Angeles' water supply system, was offline during a devastating wildfire that destroyed thousands of homes and structures nearby.

The Santa Ynez Reservoir, which has a 117-million-gallon capacity, had been drained for repairs to its cover, leaving it empty during the critical period, officials told The Times.

The reservoir's closure has raised concerns, as firefighters encountered low water pressure and dry fire hydrants in the higher elevations of the Palisades while battling the blaze. The Times reported Wednesday that these challenges hindered firefighting efforts and exacerbated the damage.

Governor Gavin Newsom responded Friday by ordering an independent investigation into the Los Angeles Department of Water and Power (DWP) over the empty reservoir and loss of water pressure, describing the situation as "deeply troubling."

“We need answers to how this happened,” Newsom wrote in a letter to DWP and Los Angeles County Public Works leaders.

DWP officials attributed the water pressure issues to the unprecedented demand during the wildfire. Former DWP General Manager Martin Adams explained that while the operable Santa Ynez Reservoir could have temporarily alleviated pressure issues, it would not have been a complete solution.

“You still would have ended up with serious drops in pressure,” Adams said in an interview. “Would the Santa Ynez [Reservoir] have helped? Yes, to some extent. Would it have saved the day? I don’t think so.”

A DWP spokesperson acknowledged that the reservoir’s closure likely contributed to diminished water pressure and dry hydrants in the upper Palisades. However, the utility is conducting a root-cause analysis to assess the full impact of the reservoir being offline.

“Our primary focus is to provide water supply throughout the city,” the spokesperson stated. “The system was never designed for a wildfire scenario of this magnitude.”

The timeline for the reservoir's closure remains unclear. Adams noted it had been out of service “for a while” due to a tear in its cover but added that DWP’s storage and supply infrastructure had previously maintained water availability citywide until this week’s crisis.