Of the insidious threats facing wildfirefighting – extreme heat, desiccated forests, unpredictable fire behavior, and a nearly year-round fire season – which might be the most daunting?
People.
People do dangerous things that start wildfires. They push a burning car into a ravine. They mow the lawn on a hot summer day. They miswire a hot tub. They drive cars with flat tires. They burn toilet paper instead of taking it with them from the campsite. They set off smoke bombs at gender reveal parties.
In hot, dry conditions where the fire risk is already high, an innocuous mistake – such as driving a metal post into parched ground – can quickly lead to a fire that kills a firefighter.
Humans – whether intentional, reckless, or simply careless – are responsible for about 95% of California’s wildfires. Last year alone, humans started more than 7,000 wildfires in California, and more than 50,000 nationwide.
“People are incredibly predictable,” said Cal Fire Battalion Chief David Acuna. “They’ll lug chains around and start campfires, or they’ll get a flat tire but think they’ll just make it to the next exit.”
“People don’t have proper judgment,” he added. “They don’t pay attention to what they’re doing and whether it’s going to start a fire or not. I believe in people’s ability to recognize what’s not in their best interest, but people prove me wrong all the time.”
Add to that the Park Fire, a devastating blaze raging across 600 square miles in four Sacramento Valley counties that is already the fifth largest in California history. Butte County authorities have arrested a 42-year-old Chico man suspected of pushing a burning vehicle into a ravine.
Human activity may also have tragically been the cause of the 57,300-acre Borel Fire in Kern County, which broke out last week on the side of Highway 178 and may have been sparked by a car crash that killed the driver.
In a summer of severe fires and dangerous thunderstorms in the coming weeks, authorities are counting on people to stop doing stupid things. Nature doesn’t need help starting fires.
That includes the man accused of driving his truck more than four miles through Sonoma County last week without a front tire. The metal scraping the road ignited the Flora Fire, a small blaze east of Healdsburg. The fire was brought under control last Sunday and a suspect is in custody. Cal Fire lists the cause of the fire as “vehicle.”
A similar maneuver sparked the Carr Fire near Redding in 2018. The fire, which killed three firefighters and five civilians and burned nearly 230,000 acres, was ignited by a spark caused by someone driving a trailer with a flat tire.
Another major human cause is due to institutions – the power companies – rather than reckless individuals. “Since 2015, power lines have caused six of the state’s 20 most devastating wildfires,” according to a 2022 report from the State Auditor’s Office. California’s deadliest fire, the 2018 Camp Fire, which killed 85 people, was started by power lines. Pacific Gas & Electric was charged with negligence and pleaded guilty to 84 counts of involuntary manslaughter.
Natural causes still play a significant role, especially lightning, which could become an even greater threat due to climate change.
Intentional arson is rare in forest fires
Arsonists who intentionally set fires are not common. Depending on the year, they are responsible for about 10% of fires in California. Last year, 111 people were arrested for arson in the state.
Thousands of man-made fires fall into the unofficial category of fools: people who do something they think is safe or, without thinking, something they later regret.
Some examples:
A smoke bomb at a gender reveal party sparked the deadly El Dorado Fire in San Bernardino and Riverside counties in 2020, which killed one firefighter and cost $42 million to extinguish.
A person using a lawn mower in Mariposa County caused the French Fire on July 4.
In 2003, while starting a fire to signal for help, a hunter accidentally sparked the Cedar Fire near San Diego, which burned 280,278 acres of land, destroyed 2,820 structures, and killed 15 people.
Faulty wiring in a hot tub sparked a fire in Lake County in 2015 that raged for more than a month.
Guns fired in the backcountry sparked the Detwiler Fire in 2017, which destroyed 134 buildings and threatened Yosemite National Park. The same cause in the same area sparked the Telegraph Fire nine years earlier.
A homeowner attempting to install shade cloth on his property used a hammer to drive a metal stake into the ground. The sparks sparked the 2018 Ranch Fire, which killed one firefighter and burned more than 410,000 acres in Colusa, Glenn, Lake and Mendocino counties.
Add to that: escaped Mylar balloons that spark power lines, unattended campfires, lawn trimmers, cigarette butts thrown out car windows, trains, fireworks in backyards, it’s a miracle the state doesn’t burn down every year.
Sending emergency crews to human-caused fires takes resources away from naturally caused fires, says Adrienne Freeman, a spokeswoman for the U.S. Forest Service.
“The answer is to use common sense,” she said. “It’s important not to look for someone to blame, but if you have a flat tire and you’re 150 yards from the gas station, you might be better off pushing (the car). Think about the bigger picture.”
Freeman said one particularly stupid decision she has seen appears to be widespread: campers in remote areas setting fire to used toilet paper so they don’t have to carry it with them.
Vehicles and lawn equipment are the main causes of wildfires
“The unsung reason is parking on dry grass. That’s common,” she said. “People drive up to a river access and see all these cars parked on the same strip as them. What do they do? They park there.”
Every summer, firefighters in California must put out countless wildfires caused by a hot exhaust pipe coming into contact with tall, dry grass beside a road. The flammability of grass is so well known that even firefighters are careful not to start fires when using or transporting equipment.
“When you’re putting out fires, you can actually start fires,” Freeman said, noting that heavy fire trucks and other firefighting vehicles can kick up rocks and create sparks. “When you move your bulldozers to respond to a fire, you have to be very careful.”
Dave Winnacker, fire chief of the Moraga-Orinda Fire District east of Berkeley, said human-caused fires are often the result of unsafe use of outdoor equipment and car accidents. His department operates a rigorous fire education program, but sometimes education and warnings are not enough. In June, the fire district imposed a nearly total ban on outdoor fires.
In many California counties, mowing the lawn early in the day or late in the afternoon is recommended, but not required.
“We rely on our education and getting the message out. Ultimately, some people will get it and some won’t,” said Andy VanSciver, spokesman for the Ventura County Fire Department.
This article was originally published by CalMatters here.
