Recent wildfire events throughout the world have highlighted the consequences of residential development in the wildland-urban interface (WUI) including hundreds to thousands of homes burned during a single wildfire to, more tragically, firefighter and homeowner fatalities. Despite substantial investments in modifying wildland fuels near populated areas, losses appear to be increasing. In this article, US Forest Service Researchers examine the conditions under which WUI wildfire disasters occur and introduce a wildfire risk assessment framework. By using this framework, the authors examine how prefire mitigation activities failed to prevent significant structure loss during the Fourmile Canyon fire outside Boulder, CO. In light of these results, the authors suggest the need to reevaluate and restructure wildfire mitigation programs aimed at reducing residential losses from wildfire.
Recent fire seasons in the western United States are some of the most damaging and costly on record. Wildfires in the wildland-urban interface on the Colorado Front Range, resulting in thousands of homes burned and civilian fatalities, although devastating, are not without historical reference. These fires are consistent with the characteristics of large, damaging, interface fires that threaten communities across much of the western United States. Wildfires are inevitable, but the destruction of homes, ecosystems, and lives is not. We propose the principles of risk analysis to provide land management agencies, first responders, and affected communities who face the inevitability of wildfires the ability to reduce the potential for loss. Overcoming perceptions of wildland-urban interface fire disasters as a wildfire control problem rather than a home ignition problem, determined by home ignition conditions, will reduce home loss.
“If our problem statement is defined a keeping wildfires out of the WUI, it is unobtainable, and large wildfires and residential disasters will continue, and likely increase. Fuel treatments do not stop fires (just change behavior), and treatment alone without Home Ignition Zone [HIZ] treatment means that the inevitable wildfire exposure will result in structure loss……..By contrast, if the problem is identified as a home ignition, mitigation of the HIZ is the most cost-effective investment for reducing home destruction, and this can be augmented with other investments.”