Advancing Ice-jam Flood Risk: Integrating Dynamic Adaptive Behavior into Agent-based Model of Fort McMurray

Human behaviors have changed as ice-jam flooding has become more prevalent, impacting both flood hazard and vulnerability as a function of flood risk. These dynamic adaptations can be developed by both governments (e.g., artificial breakup and dike installation) and individuals (e.g., flood-proofing and elevating houses). The interaction between these top-down and bottom-up measures provides a complex socio-hydrological system. However, the traditional assessment of ice-jam flood risk lacks an appropriate consideration of evolving human behaviors and their interactions with static assumptions on human adaptations. We build an agent-based model to assess the ice-jam flood risk with top-down and bottom-up adaptive strategies (artificial breakup and flood-proofing). The individuals’ behaviors are influenced by the possible reduction in flood risk at the individual level by artificial breakage over time. Also, the government’s behavior is influenced by the possible reduction in total flood risk by the dynamic adaptive behavior of individuals (flood-proofing). Thus, micro levels’ behavior can dynamically lead to macro phenomena, and macro phenomena define micro levels’ behavior over time. This model is applied to Fort McMurray along the Athabasca River, Canada, with a long history of ice-jam flooding. Also, we perform a variance-based global sensitivity analysis to investigate the individual effect of model factors and their joint effects on ice-jam flood risk. The results show that although the artificial breakage by the government leads to a regime shift and a considerable decrease in the ice-jam flood risk, it decreases the number of the newly adapted residents to flood-proofing and the role of residents in ice-jam flood risk. This study can provide a good understanding of the important role of dynamic adaptive behavior in ice-jam flood risk and pave the way for better Building flood resilience.