“If Santa Ynez would have been in service, you probably would have had some help in keeping the pressures up. It wouldn’t have been a panacea. It probably would not have lasted forever,” Adams said.
The Los Angeles Department of Water and Power did not immediately respond to a request for comment from NBC News. A department official told the Los Angeles Times that evaluations were under way to determine the impact of the reservoir’s unavailability on the fire response but also noted that the water system was not designed for such severe wildfires.
Previously, the department said it had filled all available water facility storage tanks in Los Angeles ahead of the windstorm that spread the fire, including three 1 million-gallon tanks in the Palisades area.
Adams explained that typical water service to the Pacific Palisades relies on a “trunk line” 30 inches in diameter that flows from the Upper Stone Canyon Reservoir, along Sunset Boulevard, and down toward the Santa Ynez Reservoir, which is lower in elevation.
When the Palisades Fire broke out, firefighters and homeowners began to use incredible amounts of water. Janisse Quiñones, chief engineer of the Los Angeles Department of Water and Power, previously said there was about four times as much demand on the Palisades system as is typical.
If the Santa Ynez Reservoir had been in service, water managers could have “split the system in two pieces” and used water from Santa Ynez to provide water to some parts of the Pacific Palisades, Adams said. “Santa Ynez could have acted like a small water tank and provided some relief.”
Such a move would have reduced demand and helped to increase water pressure elsewhere.
Still, he said, water likely couldn’t flow fast enough to meet firefighters’ incredible demands.
“The limiting factor was the pipe,” Adams said, adding that water infrastructure is designed to allow firefighters to extinguish a few houses or a commercial building, not a wildfire.
“Systems are designed for a typical city-based fire, not an entire city catching on fire,” he said. ”There’s no domestic water system that’s built to this scale.”
In an interview on Fox 11 Los Angeles, Los Angeles Fire Department Chief Kristin Crowley said she had not been aware, when the fires started, that the reservoir was not operating.
“When a firefighter comes up to a hydrant, we expect there to be water. We don’t control the water supply,” Crowley said.
Pre-filling the reservoir out of concern about fire risk was not impossible, Adams added, but wouldn’t have made sense since nobody knew where fires would start.
“You’d have to put it in the reservoir sitting, isolated, just in case,” he said.
And afterward, water in the Santa Ynez Reservoir would have been considered nonpotable and likely wasted.
“You probably would have had to issue a boil water notice, and if you didn’t use it, the only way to get rid of it would be to dump it in the ocean,” Adams said. “It would have been a lot like betting on the Super Bowl winner before the season, without the Rams playing a game.”
The Santa Ynez Reservoir can hold up to 117 million gallons, which is 359 acre-feet of water. One acre-foot of water is roughly equivalent to the volume of two Olympic-size swimming pools. Not all of that volume would have been available for use, however.
