By N. Bénichou, M. Adelzadeh, J. Singh, I. Gomaa, N. Elsagan, M. Kinateder, C. Ma, A. Gaur, A. Bwalya, and M. Sultan
Fires in the wildland-urban interface (WUI) have become a global issue, with disasters taking place all over the world recently. The drivers of increasing WUI fire risk—increasing population and expansion of urban areas into wildlands, and climate change—are global-scale phenomena. In the coming decades, WUI fire risk is expected to increase both in regions with a long history of fires and in regions that have had been less affected over past decades. WUI fires can cause the ignition of many structures through the spread of flames and radiant heat and the deposition of burning embers over a short period of time. This can overwhelm protection capabilities, lead to large evacuations, and cause disasters with the potential for the total loss of hundreds of structures in a few hours.
As discussed in Chapter 1 of this Guide, over the last decade, an average of 5 533 wildfires have occurred each year in Canada, involving 2.9 million hectares of wildland area. The number of evacuations caused by wildfires increased by about 1.5 evacuations per year between 1980 and 2014, with more than 20 evacuations per year after 2010. The substantial negative impacts of WUI fires were illustrated by the Okanagan Mountain Park Fire, which affected Kelowna in 2003; the Flat Top Complex Wildfire, which destroyed significant parts of Slave Lake in 2011; and the Horse River Fire, which immensely affected Fort McMurray in 2016 and was the most costly insured loss event in Canadian history. These disasters resulted in a loss of over 2 400 structures and roughly 3 400 dwelling units. Total insured losses from these wildland fire disasters and the 2017 wildland fire catastrophic events in British Columbia are currently estimated to be $4.8 billion. Despite all efforts, wildfires pose a significant challenge to the residential population, to mitigation efforts, and to existing infrastructure when located in a WUI setting. Wildfires are likely to become more severe and frequent as a result of climate change.
National Research Council Canada: Ottawa, ON. 2021. 192 pp.
