Identifying the Factors Affecting Urban Flood Vulnerability in Bandar Abbas with Emphasis on Urban Runoff Management

In this study, the flood vulnerability of Bandar Abbas was investigated using the indicators of socio-economic status, urban density, population density and building quality and TOPSIS-hierarchical method. Therefore, at first, the weight and importance of the indicators were determined based on expert opinions and hierarchical analysis method. Then the vulnerability of the city to floods was calculated using the TOPSIS method. The study area was divided into 5 urban blocks, and then the decision matrix was formed according to 5 blocks and 4 indicators. Finally, the final map of Bandar Abbas urban flood vulnerability was prepared in ArcGIS software. The results of vulnerability analysis showed that the population density factor with a weight of 0.306 is the most important. Finally, the comprehensive analysis of Bandar Abbas flood vulnerability proved that the southern and central parts of the city and urban block No. 5 have higher vulnerabilities and these parts are a high priority for urban runoff and flood management. High population density can be one of the reasons for the vulnerability of this region to floods. The development of green space and increasing the capacity of the street runoff collection system are among the important measures to reduce urban flooding. Also, the spatial distribution of population density and urban density in Bandar Abbas was unbalanced and this issue should be considered in the management plans of this city to reduce the concentration of population in areas with high vulnerability.