Flood risk assessment in Quzhou City (China) using a coupled hydrodynamic model and fuzzy comprehensive evaluation (FCE)

Abstract

To evaluate urban flood risk while considering spatial and temporal characteristics, this paper establishes an assessment method based on a coupled hydrodynamic model and a fuzzy comprehensive evaluation method. An assessment system is developed using hydrologic, social and economic factors. In addition, hydrology factors are obtained by the coupled hydrodynamic model. The hydrodynamic model is solved using the three-cascade method of the Saint-Venant equations for a river system, and the surface runoff is solved using a modified Roe-type approximate Riemann solver. The hydrology results are used as hydrologic factors and directly reflect the inundation of the subsequent assessment. Afterward, an analytic hierarchy process is used to calculate the weights of the assessment indices. Then, the urban flood risk is analyzed using the fuzzy comprehensive evaluation method. Five different rainfall events in Quzhou City are simulated and evaluated. The numerically computed results compare well with the statistical data and indicate an extreme inundation depth of more than 3 m. In addition, the assessment risk of Quzhou City is at level IV (high). This study shows that combining the assessment method with the coupled hydrodynamic model efficiently reflects the urban flood risk by considering flood, social and economic data.

An Application of Fuzzy Analytic Hierarchy Process in Risk Evaluation Model

“…Fuzzy comprehensive evaluation (FCE) is a crucial step in the assessment of the risk of conflicts in uncertain environments ( Geng et al, 2020 ). The advantage of FCE is that the contribution of multiple related factors can be comprehensively considered according to the weight.…”

Community flood vulnerability and risk assessment: An empirical predictive modeling approach

“…Flooding is the most common and costly natural hazard globally (Guha‐Sapir, 2020). To manage flood hazards effectively, a growing body of academic research has emerged aimed at improving the assessment of flood vulnerability and risk for communities around the world (e.g., Aerts et al, 2018; Cabrera & Lee, 2020; Das et al, 2020; de Moel et al, 2015; Feloni et al, 2020; Forero‐Ortiz et al, 2020; Geng et al, 2020; Glas et al, 2020; Grežo et al, 2020; Jun et al, 2020; Lin et al, 2020; Luu et al, 2020; Najafi et al, 2021; Pham et al, 2021; Sarkar & Mondal, 2020; Su, 2020; Tanoue et al, 2016; Tsakiris, 2014; Ward et al, 2020). Hydrologically oriented studies usually emphasize estimation of extent of inundation, return periods of flood events, and potential physical exposures (e.g., Gori et al, 2020; Lindenschmidt et al, 2016; Mojaddadi et al, 2017; Ward et al, 2015; Zaharia et al, 2017).…”

Assessing Permeability Controls and Flood Risks Related to Urban Impervious Surface Expansion: A Case Study of the Southern Part of Kunming City, China

“…Scenario simulation methods were used to simulate urban flooding and ponding under designed rainfall conditions . Furthermore, comprehensive urban drainage models were built based on the Infoworks ICM, different measured rainstorms were selected for simulation analysis, and the model was used to simulate the drainage capacity and ponding depth of a regional drainage network system under rainstorm scenarios with different return periods (Huang et al 2017;Wang 2018;Wang and Zhou 2018), as well as perform analyses based on multi-model coupling (Li et al 2019;Tao 2017;Geng et al 2019). In addition, CA has been used to build urban storm flood models .…”