Alene Tchekmedyian, Hannah Fry and Richard Winton – Los Angeles Times
LOS ANGELES — Los Angeles firefighters did not use thermal imaging technology to detect lingering embers underground after a New Year’s Day fire in Pacific Palisades that flared up days later to become one of the most destructive infernos in the city’s history.
Interim Fire Chief Ronnie Villanueva said in an interview this week that fire officials decided against employing the technology, which would have pinpointed heat underground, because of the fire’s eight-acre size.
In the 36-plus hours that crews spent mopping up the Jan. 1 fire, which federal prosecutors say was deliberately started along a popular hiking trail, firefighters “cold trailed” the perimeter, chopping a line around the fire and feeling for residual heat. They packed up and left on Jan. 2, then returned the next day, after a report of smoke in the area, for another round of cold trailing, Villanueva said Wednesday.
Villanueva downplayed the effectiveness of the thermal imaging cameras, noting that some chaparral in the city extends 15 to 25 feet underground, while the depth of the department’s cameras is only a foot.
“We did everything that we could do,” he said.
Los Angeles fire officials, already under scrutiny for their failure to pre-deploy engines in advance of the Palisades fire, are facing questions about why they didn’t fully extinguish the Jan. 1 fire before hurricane-force winds fanned an ember buried within the roots of dense vegetation on Jan. 7. The Palisades fire killed 12 people, charred 23,400 acres and leveled more than 6,800 structures, including many homes.
On Wednesday, federal prosecutors released documents charging a 29-year-old Uber driver with intentionally setting the Jan. 1 fire, called the Lachman fire. The documents also revealed the results of a federal investigation into the cause of the Palisades fire, which concluded that it was a “holdover fire” — defined as a fire that remains dormant for a considerable time.
An LAFD after-action report also released Wednesday described shortcomings of the department’s response to the Palisades fire, along with recommendations for improvement, but did not address the failure to prevent the “holdover” from the Lachman fire.
Fire agencies across the country, including the LAFD, often deploy drones or aircraft with thermal imaging to detect lingering heat or hot spots in a fire.
Ed Nordskog, a former arson investigator with the Los Angeles County Sheriff’s Department, was critical of the agency’s decision not to deploy the thermal imaging, calling it “hard to justify.”
“It is not extraordinarily difficult to do,” Nordskog said of deploying the technology. “It is specifically used to prevent rekindle fires. It is normal protocol to do it and then send back a couple of firefighters to check again.”
He added: “If they have those items and failed to employ them, that would be a major error.”
Fire experts said that in some environments, a blaze can rekindle days and even months after the initial fire is thought to be extinguished. Embers can bury deep in tree roots and chaparral, become covered in heavy ash and continue to smolder until strong winds set them free. Nordskog said that thermal imaging is the safest way to spot such embers.
It’s typical for rekindling to happen when firefighters are still on the scene, allowing them to get control of the situation quickly. But some destructive fires, including the 1991 Oakland Hills fire and the 202