A brush fire that's burned 5,208 acres since breaking out Wednesday in the Castaic area is 87% contained as of Sunday morning, with firefighters battling punishing triple-digit heat along with the flames.
The Route Fire, which began around noon Wednesday alongside the 5 Freeway north of Lake Hughes Road, has destroyed two structures, threatened 500 more and led to seven heat-related firefighter injuries.
Overnight, firefighters continued to reinforce fire lines and focused on boxing the fire in because of more excessively high temperatures in the forecast. Triple-digit highs are expected in the area through the Labor Day weekend and into early next week.
Bolstered by the addition of two Super Scooper water-dropping aircraft, hundreds of firefighters on the ground and in the air continued their assault, working to extend a containment line around the blaze, according to the LA County Fire Department.
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The two right lanes of the northbound 5 Freeway between Lake Hughes Road and Templin Highway were closed Saturday and expected to stay that way though the holiday weekend, Caltrans reported. Retaining walls burned, and structural engineers must inspect wall integrity before any load is put on lanes, Caltrans said.
Ridge Route Road remained closed between Templin Highway and Pine Crest Place to all but local access and emergency crews.
The seven firefighters who suffered heat-related injuries Wednesday have all been released from the hospital and were "doing well," authorities said.
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There were no reports of any other injuries.
One home along Ridge Route was destroyed, and a separate outbuilding in a different location was damaged, Angeles National Forest Fire Chief Robert Garcia said Thursday.
"There was a lot of opportunity with this fire behavior yesterday (Wednesday) for this to go far worse than it did," Garcia said. "So, thanks to our partners for keeping the public and our firefighters safe."
“The headline for us on the Angeles National Forest is going to be the conditions we're in now,” he told reporters. “The fire behavior and what you saw yesterday should be a wake-up call to us all about the potential that we're in and we're entering into over the next few days in terms of the fire conditions. Very rapid fire growth and very, very explosive fire behavior.
“And so the message from the Angeles National Forest is that the days ahead are going to be very challenging,” he said. “So we ask for full cooperation for our public that's visiting the national forest and those that live in and around the national forest, that based on those conditions we please ask you to heed the warnings of our conditions, our fire danger level, and our fire restrictions and of course closures and evacuations should a fire emerge in your area.”
The fire broke out around noon Wednesday alongside I-5 north of Lake Hughes Road. The freeway was briefly closed in both directions as flames jumped the northbound lanes and began creeping toward the southbound lanes.
An evacuation order issued Wednesday afternoon for the Paradise Ranch Mobile Home park in Gorman was lifted Thursday, along with an order for homes along Ridge Route Road.
The LA County Fire Department and the Angeles National Forest were working as a unified command, with 467 personnel battling the fire as of Saturday.
Cal Fire, the LA County Sheriff's Department and CHP were also assisting.
Fire officials said they would work to keep the fire west of Castaic Lake, east of Palumas Canyon, south of Fall Creek and north of Lake Hughes Road.
LA County Supervisor Kathryn Barger, who represents the area, hailed the “Herculean” efforts of fire crews braving the heat and difficult terrain to beat back the flames.
"Their labor is also a reminder for us all to practice responsible and safe recreation as the Labor Day holiday approaches,'' Barger said in a statement. "Most wildfires are caused by human carelessness. Campfires, discarding lit cigarettes, playing with fireworks -- all can trigger a blaze. We all need to do our part to keep our communities safe."