CalFire released the last of its updated fire hazard severity maps on Monday, showing a 3.5 million acre expansion of Southern California’s zones. The largest increases were in the Antelope Valley and the Inland Empire. It’s the first update to these hazard zone classifications since 2011.
The Golden State’s top fire agency published the color-coded maps to show how much of the state is fire-prone and how intensely a fire might burn. These maps only cover, however, areas where local fire departments are responsible for fighting blazes.
Using climate, geographic and weather data, CalFire split an area’s fire risk into one of three categories: “moderate,” “high” and “very high.”
In LA County, areas deemed “very high” jumped by 30%.
“You expect from year-to-year that these hazard maps wouldn’t change,” says Ben Christopher, housing reporter for CalMatters who wrote about the updated maps. “And yet, the amount of ‘high’ and ‘very high’ hazard areas across the state has really exploded since the last time CalFire put these maps together.”
In total, California now has 3,626 square miles identified as fire risk zones – an area nearly twice the size of Delaware.
Christopher points to multiple reasons the fire hazard zones have grown significantly in 14 years.
First, CalFire used a more sophisticated model to determine risky areas. The agency went as far as to predict how big embers might be when a certain patch of land burns, as well as how far those embers might spread.
Second, the 2011 maps only identified “very high” hazard zones. This time around, the scope was expanded to include “moderate” and “high” fire risk areas.
Lastly, climate change. “Warmer climate means drier fuels, hotter weather in some cases, more severe wind patterns,” says Christopher. “So that all contributes to much more fire risk.”
These maps are referenced in nearly 50 state codes, including those that address highways, health, safety and construction. Most importantly, the maps are also used to determine what areas should be required to follow certain fire safety regulations – like requiring fire-resistant windows or keeping brush away from homes.
“So if you’re building a house or rebuilding a house – as is the case in a lot of parts of LA – you’re going to have to meet these enhanced building codes,” says Christopher.
CalMatters estimates that about 3.7 million Californians now live in fire hazard zones and will have to comply with these mandates.
“Many will be older homes that are very vulnerable to wildfire. So that presents a massive problem for homeowners and for the state of California as a whole to figure out how to get these folks in a position where they are going to be safer when it comes to wildfire risk,” Christopher says. “There are many more households and people who are going to be subject to these rules going forward — including parts of the state that recently burned like Altadena.”
As more frequent and destructive blazes in California have pushed home insurance prices up, CalFire says their fire hazard maps have no direct impact on rates. Regardless, Christopher says these maps are not revealing any information that insurance companies don’t already know.
“They have their own maps, their own models, and those models actually factor in many more things that CalFire is not including,” he says.
