Dynamic Assessment of Urban Flood Resilience and Recovery under Climate Change: The Case of Rende District, Tainan, Taiwan

Taiwan is prone to flood risks based on its topographic condition characterized by steep slopes, short and flashy river courses, and high-density levels in the plains, which are susceptible to extraordinary rainfall associated with typhoons and monsoon systems. The current climate change projection indicates the likelihood of enhancement in the hydro-meteorological risks, which will not only intensify the flood hazard but will also make it more complex in terms of recovery in urban areas. In this respect, the traditional flood hazard assessment, based mainly on the instant damage, is not effective in reflecting the actual flood hazard resilience that is dependent on the recovery process.This work uses the Interdependent Networked Community Resilience Modelling Environment (IN-CORE) for flood damage assessment and the process of recovery for buildings, roads, and bridges in Rende District, Tainan, which is flood-prone in southern Taiwan.A comparative, scenario-based framework will be applied to explore how climate change might influence both flood-induced damage and the post-disaster recovery process. One base-case scenario will consider historical flood hydrological conditions and inundation extents to evaluate the probably expected damages and recovery rates of interdependent urban systems. Subsequently, this base case will be compared with future scenarios of extreme floods, driven by increased precipitation intensity and duration according to CMIP6 (Coupled Model Intercomparison Project) climate projections, which then provide climate-amplified hazard inputs.The damage assessment piece will examine the spatial distribution and severity of structural damage to buildings and infrastructure, while the recovery assessment piece will examine the temporal profile of the functionality of the systems, taking into account the dependencies in the infrastructure systems such as roads and bridges, the accessibility, and the sequence of the cleanup activities.Under this framework, the patterns of recovery of infrastructure systems will be evaluated with respect to not only geographic patterns of damage but also with respect to potential system constraints that can lead to delays in the functioning of the system during intensified flooding caused by a changed climate.In conjunction with the explicit incorporation of the flood hazard properties of Taiwan and the simulation of recovery over time, this work develops and applies to the field the transferable approach to assessing flood resilience dynamics. This is especially relevant to cities threatened by the growing flood risk posed by the increasing product of climate and sea/monsoon patterns.Keyword: Urban flood resilience, post-disaster recovery, Climate change impact, Taiwan