The Camp Fire that tore through the communities of Concow and Paradise in Northern California in 2018 was the deadliest and costliest in Californian history. Some 150,000 acres burned, causing 50,000 people to flee, 20,000 structures to be destroyed, and some $16.5 billion in damages. 85 people lost their lives.
Strangely, amid all this destruction, which was sparked by downed electrical lines owned by PG&E, the state’s power utility, some homes survived. Why?
At a session at the American Planning Association in San Francisco, wildfire experts explained how to use these approaches as well as the broader importance of land use, community planning, and landscape design in fire safety.
According to Edith Hannigan, with the California Board of Forestry and Fire Protection, Concow and Paradise and many other communities across the west are at high-risk because they formed in the wildland-urban interface (WUI), which the U.S. Forest Service describes as places where “humans and their development meet or intermix with wildland fuel.” On top of the intrinsic risk of simply existing in the WUI, these communities must now contend with the effect of years of drought, bark beetles onslaughts on surrounding forests, and climate change, which create increasingly dangerous and untenable living conditions.
Living in the WUI raises risks for all property owners, but lot locations, sizes, layouts, and topography impact risk levels. To provide “meaningful reduction of risks for specific situations,” California Department of Forestry and Fire Protection (Cal Fire) created a land-use planning program, with two fire chiefs and ten local fire captains, that “reaches out to communities and provides technical assistance,” meeting the goals of the state’s recent strategic fire plan.
For retired Cal Fire captain David Shew, who oversaw the creation of the program and is now a consultant, wildfires “aren’t a fire department problem”; they are really a land use and community design problem. The solution is to respect natural systems and stop developing communities in the WUI. For those communities already there, it’s important to incorporate better planning and design approaches to reduce the danger.
California, like Greece, Australia, Sweden, and other parts of the world, has a “natural fire environment” in which wildfire has evolved an important role in maintaining the health of the ecosystem. Native Americans lived with the natural wildfire cycle for centuries, but the settlers moving across the West in the 1800s were unnerved by constant small wildfires. As settlers formed communities that in turn suppressed fired, the natural fire state ended. It turns out it was “the hubris of mankind to think we can control Mother Nature.” Over the decades, dead plant material that hasn’t been allowed to burn naturally has accumulated, so now when it does burn, the wildfires are larger and more destructive.
Mother Nature has recently made her voice louder. California sees more wildfires than ever before — and now they occur throughout the year. “There is no longer a fire season.” 9 out of 10 of the most destructive fires occurred since 2013. In 2018 alone, there were some 5,800 fires that consumed 1.3 million acres. And greater dangers loom: there are 100 million dead trees in the Sierra Nevada area that will fall over and create more fuel for fires. Shew said: “We have disrupted evolution and the result will be devastating wildfires.” (One solution to prevent this may be controlled or prescribed burns).
Wildfires themselves often don’t cause homes to go up in smoke; “it’s flying embers that cause most fires.” Wood fences and gutters often catch first, spreading to homes. Building and landscape “materials are really important, but where a structure sits on the landscape, and where and how homes cluster, also are.”
Michelle Steinberg, director of the wildfire division with the Natural Fire Protection Agency (NFPA) — creator of codes and standards state and local governments use to protect communities and the Firewise USA program, which includes some 1,500 sites — got into the details on how to use smart codes designed for different community types. The codes provide rules for crucial evacuation zones, the materials and layout of residential structures themselves, and the landscape around a home and community, including common spaces.
The residential landscape is re-imagined by NFPA as the “home ignition zone (HIZ),” a concept developed by retired U.S. Forest Service fire scientist Jack Cohen in the late 1990s, following “some breakthrough experimental research into how homes ignite due to the effects of radiant heat.” The HIZ has three zones: 0-5 feet from the house, which is the immediate zone; 5-30 feet away, the intermediate zone; and 30-100 feet, and out to 200 feet, the extended zone.
In the immediate zone, there can be no trees and vegetation and all materials need to be fire-proof. In the intermediate zone, lawns need to be trimmed, debris cleared, and trees need to be well-spaced and set within small clusters. In the extended zone, all dead trees and plants need to be removed.
Wildfires are a major problem elsewhere in the U.S. Molly Mowery, with Community Planning for Wildlife (CPAW) in Colorado, a joint partnership between Headwaters Economics and Wildfire Planning International, explained how she is helping communities across the country assess risks and apply planning and design solutions to reduce their exposure to wildfire.
For example, working with Summit, Colorado, CPAW helped spur the development of new regulations and zoning that require defensible space zones in subdivisions, prohibit the planting of flammable juniper trees within 30 feet of homes, and require non-combustible fencing and safer firewood storage within 5 feet of homes. Mowery said many communities struggle with seemingly-insignificant things like fences, but they are often the cause of property-destroying conflagarations.
Download a free APA resource — Planning the Wildland Urban Interface, which was partly financed by the U.S. Forest Service. Check out the case for prescribed burns to reduce wildfire risk. And see how landscape architects at Owen Dell and Associates design Firewise gardens.