Mapping wildfire hazard, vulnerability, and risk to Canadian communities

Abstract

Large and intense wildfires are an integral part of many Canadian landscapes, playing a critical role in ecosystem dynamics. However, the recent catastrophic fire seasons have highlighted the threat that wildfires can pose to human communities. Identifying areas at higher fire risk is therefore crucial in order to mitigate the impacts of wildfires on society. This study presents a standardized method for a nationwide wildfire risk assessment, focusing on buildings and populations. Using the Burn-P3 wildfire simulation model, along with building footprint and census data, we generated wildfire hazard, vulnerability, and risk maps for Canada’s forested regions. Our findings demonstrate the nuanced understanding of wildfire risk when considering the interaction between fire hazard and physical vulnerability. Approximately 32.3% and 6.3% of the land are classified as High and Very high fire risk, respectively. We estimate that 111,519 units (5.8%) of directly exposed buildings are classified as High fire risk, and 10,622 units (0.6%) as Very high fire risk. Moreover, we found that approximately 283,200 people reside in areas at High fire risk, while 30,500 people live in areas classified as Very high fire risk. Indigenous on-reserve communities are particularly vulnerable to wildfire impact. We estimate that 18.9% of people living in Indigenous reserves reside in areas at higher risk of fire, compared to only 2.4% for the non-reserve population. The present study offers critical information for the development of a national wildfire risk management policy and provides new insights that support the implementation of effective measures for wildfire risk reduction.