Factors influencing flood risk mitigation after wildfire: Insights for individual and collective action after the 2010 Schultz Fire

Post-fire flooding is of significant concern in the U.S. Southwest, where burned areas can drastically alter local hydrology to increase the risk of floods and debris flows, posing new and dynamic flood risk to communities downslope that necessitate coordinated response across jurisdictional boundaries. However, limited research explores how residents in affected communities respond to post-fire flood risk, both individually and collectively. We address this need by exploring factors that may influence the uptake of individual and collective actions for post-fire flood mitigation after an extreme fire event. We conducted a mixed-mode survey of 1,804 households in Flagstaff, Arizona, within the 100-year modeled post-fire flood risk area created by the Schultz Fire in 2010. We received 407 completed questionnaires for a 22.6% response rate. Survey questions focused on mitigation actions, addressing community flood risk, and responsibility for post-fire management among other topics. We found that respondents most readily engage in temporary mitigation actions, such as sandbag placement, that require less time and lower financial commitment. Respondent mitigation actions were primarily influenced by their personal flood experience and risk perceptions, with concerns about longevity of flood risk prioritized above current risk levels. Those who participated in individual actions were more likely to participate in collective action and vice versa, indicating a close relationship between mitigation actions across scales. We provide implications for practitioners working in post-fire environments, with a focus on communication and outreach about flood risk that motivate resident action to facilitate shared responsibility and cross-jurisdictional management of post-fire flood risk.