Integrating social vulnerability with structure density and hazard to improve community wildfire risk assessments

Abstract Decision support tools play an important role in determining how to strategically allocate limited wildfire risk reduction resources. However, common decision support tools generally do not account for socioeconomic or demographic characteristics which influence community vulnerability to wildfire, resulting in potentially biased risk reduction investment strategies. To address this limitation, we demonstrated how two common decision support tools, a social vulnerability index and a quantitative wildfire risk assessment (QWRA), could be integrated to create a more equitable assessment of community wildfire risk for the Pacific Northwest region of the United States. We evaluated the potential impact of social vulnerability on a risk reduction prioritization strategy by summarizing risk within communities ( n = 1005) and ranking them. We compared the results to a conventional QWRA which lacked any social vulnerability data. The inclusion of social vulnerability in the QWRA increased the risk for 459 communities. As a result of including social vulnerability, we identified 26 new priority communities all located in high hazard landscapes. Results indicate that a socially informed risk assessment may support a more equitable distribution of risk reduction resources by balancing the significance of hazard, exposure and social vulnerability. Policy makers, community leaders, and resource managers can use these risk assessment outputs to identify communities that are a priority for mitigation investments including capacity building, planning, education and critical infrastructure hardening.