Integrated Flood Risk Assessment System Based on the Set Pair Analysis and Variable Fuzzy Sets for Cascade Dams

Abstract

Flood-caused dam break is an important dam safety problem. Dam flood risk assessment based on an appropriate assessing method is hence essential for reducing dam-break flood damages and losses. In this research, a comprehensive flood risk assessment system for cascade dams was developed by combining the set pair analysis (SPA) and variable fuzzy sets (VFS) theory (namely SPA-VFS for short), and expressing the flood risk as a product of hazard and vulnerability, which were quantified by selected indicators. In the case study of the Dadu river basin, reservoir capacity, dam height, dam age, gross domestic product (GDP) density, population density, and predicted damage were selected as the evaluation indicators, and the evaluation results derived the flood risk classes of each studied dam. The study indicates that the proposed SPA-VFS-based flood risk assessment model is simple and feasible, which enables its further application in flood risk analysis and evaluation, and its extension in the risk assessment of other natural disasters.