Topanga Canyon’s nightmare fire scenario begins in the middle of the night when everyone’s asleep at home.
As blustery Santa Ana winds blow in from the east, a spark from a powerline or a passing car drops onto dry brush, starting a fire along the edge of the San Fernando Valley. As the flames grow, emergency services send out alerts, waking up thousands of residents throughout the area, telling some to shelter in place and others to leave.
It’s an increasingly likely situation as our vegetation dries out and winds pick up, according to Drew Smith, fire behavior analyst with L.A. County Fire.
“I would not be surprised,” Smith told me as we stood atop a helipad looking across the Transverse Ranges. “We are training for that.”
With only a few arteries in and out of the canyon, Smith warns that a fast-moving wildfire could trap people on the canyon’s narrow roads, consuming everything in its path.
In a worst-case scenario, the fire explodes into a devastating tragedy akin to the 2018 Camp Fire in Butte County, which destroyed the town of Paradise, trapping people trying to escape. At least 85 people were killed.
“That’s one thing that keeps me up at night,” he said. “That worst-case scenario fire with our residents at home with limited options. It’s terrifying.”
It’s difficult to emphasize just how dangerous wind driven fires can be, especially where we were standing, near the top of Stunt Road, above Calabasas.
Looking out across the Santa Monica Mountains, you can see small communities tucked in between dense chaparral that hasn’t burned in 30 plus years. Meaning, there’s a whole lot energy ready to fuel fires that roll through.
If the Santa Ana winds are blowing, strong gusts can throw embers more than a mile ahead of a fire front, starting up spot fires all over.
And because of the steep and rocky terrain, firefighting hand crews and bulldozers might struggle to dig fire lines meant to help contain the fire.
Even with water drops from helicopters, containing a fire in nightmarish fall conditions can be all but impossible.
“We know that fire history tells us on a high risk day, if we don’t suppress a fire within the first 10 minutes, it has a high probability of extending to the Pacific,” Smith said.
Smith estimates that it'd take one of these worst case scenario fires about four hours to sweep westward, from the San Fernando Valley to the Pacific Ocean, destroying communities along the way. Just as we saw during the Woolsey Fire in 2018, which made its way 17 miles across L.A. to Malibu in less than 24 hours, destroying 1,600 structures and killing killing three.
"Don't get lured into a false sense of security because we've had a very passive fire season in Los Angeles County," said Smith. "Under the right conditions, we have a high potential for a devastating fire in the Santa Monica Mountains that hasn't seen fire frequency in 25 years."
Topanga isn't the sole community at risk, the threat really applies to those throughout the Santa Monicas.
The helipad Smith and I were standing on is called 69 Bravo, and it’ll likely be one of the most important staging areas for firefighters when one of these fires does break out.
It sits at about 2,600 feet above sea level, offering views of Newhall Pass on one side and the Pacific on the other. Below the pads are four 8,000 gallon water tanks that automatically refill, there to be drawn on by helicopters and fire trucks that are working to head off flames on their run to the ocean.
You can see a live view here.
It’s quite likely that many fires will be started – all by people – in the coming months. Though, each won’t become a Woolsey level event.
So how do you know if you should be worried?
Smith laid out some of the key conditions he looks for to figure out if a fire is going to move fast:
If you want to keep it simple, look out for red flag warnings from the National Weather Service, which indicate that extreme fire behavior is possible.
Check out their Fire Weather Snooper, which presents data from weather stations that are entering or in red flag territory.
On average we get eight red flag events per year, according to Smith, and on average each lasts three days.
It’s always a good time to prep for disasters, especially before a red flag event arrives:
Sign up for emergency alerts in your area
If you live in a high risk area like Topanga Canyon and a red flag event is on its way:
Unsure if you live in a high risk area? Check out the state's Fire Severity Zone map for your county.
How did wildfire risks get so bad? What can you do to stay safe? We have answers in our 2022 podcast, "The Big Burn," from LAist Studios.
