Five years ago, the Black Summer Bushfires burned more than 60 million acres in Australia. Between June 2019 and May 2020, hundreds of fires burned, mainly in southeastern Australia. Like the recent fires in Los Angeles, Australian bushfires are driven by high winds. They tend to burn more intensely and advance more rapidly than U.S. forest fires.
Because of the well-documented wildfire threat, Australia had already developed a “strong institutional structure and community social capital” for “prevention, mitigation, and management” of wildfire risk, according to a post-fire assessment by Australian researchers. These assets include well-established organizations, systems, and legal contingencies at the local, regional, and national levels. The Australian lessons-learned report “underscores the importance” of the proverbial ounce of “pre-disaster prevention” over a pound of “emergency response” cure. A key component of Australia’s strong institutional structure is its community wildfire response policy: Stay and Defend or Leave Early (SDLE).
Sarah M. Mccaffrey, a Ph.D. scientist at the U.S. Forest Service Northern Research Station, co-authored a report comparing the Australian SDLE approach to the U.S. total evacuation response. The report acknowledges the easily promoted crowd-control, common-sense “simplicity” of the U.S. approach. But the report demonstrates, “The growth of housing in the wildland-urban interface (WUI) has contributed to the current fire management challenge” by multiplying “the potential complexities of evacuation. … In Australia, large-scale evacuations in response to wildfire have not been widely used.”
Instead, Australian fire management agencies follow a “common-sense” approach to wildfire. Residents are encouraged to “accept responsibility for how they will respond to the threat of wildfire,” which “greatly reduces the risk to firefighters.” The SDLE approach encourages residents to decide well before a fire occurs whether they will choose to leave when a fire threatens or “stay and actively defend their property—and to make appropriate preparations in advance for either option.”
Appropriate preparations focus primarily on home/structure hardening and secondly on defensible space. For Australia, home hardening includes fire bunkers — the fire-equivalent version of mid 20th-century tornado cellars on farms across the Great Plains. (“Toto, I’ve a feeling we’re not in Kansas anymore.”)
Unlike the U.S. strategy of total evacuation, the SDLE strategy is “well supported by extensive research on how houses ignite and are destroyed in wildfire and the circumstances in which civilians die in wildfires.” Australian research shows that civilian deaths most often occur because of “radiant heat exposure” when people are caught in the open “while trying to flee at the last minute.”
Over the past 100 years, 78% of Australia’s civilian wildfire fatalities occurred when people tried to flee. Ten percent of deaths occurred when people were passively sheltering, and 2% died while actively defending their property. While U.S. research into civilian wildfire deaths is limited, an analysis of the 2003 Cedar Fire in Southern California found that almost all the 22 civilian deaths occurred while individuals were evacuating at the last minute.
Australian research also shows that most houses are destroyed “by fires igniting from embers entering or landing on the house either before, during, or over a long period after the fire front has passed.” Post-fire studies in Australia indicate that, when someone is present and actively defending the property, “there is a greatly increased chance that the house will survive.”
Research by Forest Service scientists like Jack Cohen and Mark Finney at the Missoula Fire Sciences Lab has reached the same conclusions. Anecdotal stories from U.S. homeowners who refuse to evacuate suggest that they often save both their homes and those of neighbors by extinguishing embers and spot fires.
Australian residents are provided with all of this information so that they can make informed decisions. Those who decide to leave are told to “leave early, well before the fire is in the immediate area and travel on roads becomes dangerous.” Residents who choose to “stay and defend” are advised to prepare in advance by implementing home-hardening protections and fuels management in the home ignition zone.
The report concludes that many U.S. communities could benefit from adopting a SDLE approach with proper preparation: “There will be a need for widespread understanding of and agreement about the alternative and its potential benefits.” Achieving that level of understanding and agreement will require:
- Substantial education and outreach to ensure that residents and fire personnel fully understand the risks and choices.
- Effective partnerships between communities and fire management agencies.
- Agency structures and processes that support the policy.
- Individuals and communities willing to accept responsibility for their own safety.
