Advancing Ice-jam Flood Risk Assessment Using Agent-based Modeling: a Conceptual Framework on Human Adaptation

Human behaviors have changed as extreme events like ice-jam flooding have become more prevalent, impacting both flood hazard and vulnerability as a function of flood risk. These adaptations can be developed by both governments (e.g., artificial breakup, sediment dredging, 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. The "levee effect" or "safe development paradox" is a well-known phenomenon that may emerge out of this complex system. In fact, governmental flood protection can create a sense of safety and may lessen local households' incentives to make independent adaptations. This governmental measure may paradoxically lead to worse outcomes in the event of an extreme flood occurrence. However, the traditional assessment of ice-jam flooding lacks an appropriate consideration of evolving human behaviors with the static assumptions on human adaptations. In this study, we propose a socio-hydrological framework to assess the long-term ice-jam flood risk with associated adaptive strategies through agent-based modeling. This framework is applied to Fort McMurray along the Athabasca River, Alberta, Canada, which has a long history of ice-jam flooding. This framework can be used for exploration and scenario analysis of future ice-jam flood risk and related adaptive strategies.