Systematic Quantitative Risk Analysis of Water Shortage Mitigation Projects Considering Climate Change

摘要

Climate change causes precipitation to be increasingly unstable both spatially and temporally and, thus, is a major factor contributing the risk of a water deficit in Taiwan. Because many planned water shortage mitigation projects lack extensive risk evaluation of this problem, this risk might strongly affect the stability of regional water supply. Therefore, the purpose of this study was to consider climate change in a systematic quantitative risk analysis of water shortage mitigation projects. Accordingly, this paper proposes a process for integrating the method for downscaling global climate models, generalized watershed loading functions rainfall-runoff model, system dynamics approach, and Monte Carlo simulation to evaluate water projects practicably and quantitatively. The proposed methodology was verified using a practical case study of Northern Taiwan and can be used to make decisions regarding project implementation priorities and alternatives. While every alternative of 11 proposed projects can reduce at least 9 % of the shortage risks for both Taoyuan and Banchia-Hsintien regions, five alternatives can reduce the risk to less than 1 % for the Banchia-Hsintien region. And simulation results indicate that expanding water plant is the first priority for the study area. Furthermore, the proposed concepts and procedures are applicable to other areas.