Flood mitigation through riparian detention in response to climate variability - a case study in Taiwan

Abstract

Considering that urban areas may suffer more substantial losses than riparian farmlands during floods, diverting floodwater into riparian areas for temporal detention is expected to mitigate flood damage in downstream urban areas. In this study, an assessment has been conducted to evaluate the effect of flood mitigation through riparian detention in response to climate variability in the Tou-Chien Basin of Taiwan. A couple 1D-2D model was used to simulate the flood wave transporting in the main stream and the overbank flow inundating into the urban areas. Based on the numerical simulation results, flooding extent and inundated water depth corresponding to different return periods with current flood prevention infrastructures were detailed investigated. Various riparian detention strategies were proposed to alleviate severe losses in the downstream urban areas of the Tou-Chien Basin.