November 22, 2024

The Wildfire Risk in America’s Front Yards

6 min read

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If you live in a single-family house, chances are it’s made, or at least framed, with wood. Older homes may well also have a wood roof, and perhaps a wood deck. There might be a neat stack of firewood and wicker furniture on that deck, not to mention some synthetic carpets, curtains, and couches inside. In the face of wildfires, this home construction is an inferno waiting to happen. Embers, sometimes traveling miles ahead of a flame front, might land on the roof, catching it on fire then penetrating vents and starting to burn the interior. The house itself would then start launching embers, its radiant heat hot enough to ignite a nearby home. Pretty soon, a whole neighborhood can go up in flames.

In the past decade alone, millions of acres and thousands of homes in the U.S., mostly in the West, have burned in wildfires. So far, national and state approaches emphasize wildfire risk reduction in our forests. But it isn’t just trees fueling wildfires. Our houses are fuel, too. As fires grow in size, intensity, and frequency, experts say we need to tackle the most intimate part of wildfire risk—our own homes and neighborhoods.

According to a report called “Missing the Mark,” published last year by the Columbia Climate School and Headwaters Economics, an independent, nonprofit research group based in Montana, the most effective strategies to reduce communities’ wildfire risk aren’t just those that focus on forests, but also those that construct and adapt our homes and neighborhoods. Yet the analysis found that strategies to manage the built environment receive less funding and policy support in the U.S. than traditional approaches that focus on what’s happening in the forest.

Why doesn’t American society focus on wildfire risks at home as much as we do in the forest? And why are state and municipal building codes more common for flood- and earthquake-prone, but not wildfire-prone, areas? Kimiko Barrett, a researcher at Headwaters Economics and a co-author of the report, says it all comes back to the country’s expectations of the Forest Service, which was tasked with controlling wildfires following the Great Fire of 1910. These fires burned 3 million acres across Washington, Idaho, and Montana, and killed at least 85 people shortly after the agency’s inception in 1905, giving it a newly urgent purpose: putting out fires before they got anywhere near that big. For decades, the Forest Service and other land-management agencies’ norm has been to quickly suppress new fires when they start, using aircraft, bulldozers, and other expensive methods that receive regular funding. State, tribal, and federal land-management agencies also remove excess flammable vegetation by hand, machine, or prescribed fire.

A 10-year plan from the Forest Service calls for removing much more of this combustible kindling, reducing flammable fuels on up to 50 million acres of land. But communities will continue burning if leaders don’t also find the money and political will to retrofit older homes, and rethink where and with what new homes are built. “We assume that we can place our house in an area of high risk, and that firefighters will come in and risk their own life to protect our home,” Barrett said. “You would never assume that level of home protection from any other hazard, particularly from earthquakes or floods or hurricanes.”

According to FEMA, one-third of Americans live in the wildland urban interface (WUI), where homes mingle with forests and other vegetation. In the West, there’s been an almost 50 percent increase in the number of housing units built in the WUI from 1990 to 2020. (A new article in the Proceedings of the National Academy of Sciences journal argues that, in California, housing affordability is the main driver of migration to the WUI since the 1990s, as a growing number of people are priced out of urban areas.) Yet only California, Nevada, and Utah have statewide mandatory building codes specific to wildfire risk. California’s is by far the most comprehensive. New homes built to code post-2008 in California were 40 percent less likely to burn down in a wildfire than homes built in 1990, prior to the requirements, according to an analysis by the National Bureau of Economic Research.

Good codes include everything from using fire-resistant building materials to constructing streets wide enough for residents to evacuate and emergency vehicles to rush in at the same time. “Protecting the outside envelope of the house, and especially the roof, is the most important thing a building code can do,” Lisa Dale, a lecturer at the Columbia Climate School and co-author of the report, told me. Wood shake roofs are a no-no; asphalt or metal are better choices. Double-paned windows resist radiant heat, and clearing a defensible space free of flammable materials like vegetation around your house avoids giving embers a friendly, burnable place to land.

Oregon, Washington, New Mexico, and Colorado are all in various stages of adopting their own versions of the International Wildland-Urban Interface Code to compel homeowners to mitigate wildfire risk on their properties, Barrett told me. (States can amend and tweak the code to make it work for their unique environments.) Authors of the “Missing the Mark” report argue that state governments should encourage such mandatory building codes in wildfire-prone areas: Although voluntary codes are better than nothing, Dale said, mandating these changes can help protect communities at scale. If you remove flammable materials from near your house but your neighbor doesn’t, your house still might burn down.

Zoning and land-use planning are also under-utilized tools that can make communities more fire-resilient. “I don’t know of any municipality that’s successfully zoned for wildfire,” Dale said. With no precedent, what this could look like is unclear; lowering the number of homes in a given area and spacing them out to reduce house-to-house emissions isn’t practical or viable, but requiring that residents clear a “fuel break”—a strip of land free of flammable vegetation—around subdivisions could be.

Focusing not just on forests but also our front yards is much easier said than done. Homeowners’ desire to control their property can quash state or federal efforts in their infancy. In Oregon, legislation was passed in 2021 that required state officials to regulate home-hardening measures that can help defend structures against wildfire. But the backlash from residents to a risk map laying out where some of these requirements would be needed was so severe, the state pulled the map entirely. Another iteration was just released. A strong private-property ethos can also limit what lawmakers want to fund: “Legislators would say to me, ‘I don’t want to pay for someone’s landscaping,’” Dale said.

Then there’s industry opposition. When Dale worked as the assistant director of the Colorado Department of Natural Resources, she saw firsthand how builders and real-estate agencies shot down recommendations to implement building codes and zoning. And local governments, which receive much of their revenue from property taxes, might be disincentivized to limit new development, even if it’s proposed in a risky area.

And yet, Barrett told me, history offers hope about humans’ ability to change and adapt to wildfire. She reminded me of the story of progress that the fire historian Stephen J. Pyne has tracked. Once, America built its cities out of incredibly flammable materials. They kept catastrophically burning down—there was the Chicago Fire of 1871, then the 1906 earthquake and resulting fires in San Francisco. In the decades that followed, elected officials and other decision makers started making changes: Evacuation protocols, smoke detectors, and fire alarms were more widely implemented. Wooden boardwalks and sawdust for insulation eventually became relics of the past.We know how to make our homes and communities safer. Each fire season offers us an opportunity, and a warning, to start doing so.