University of Tehran Journal of Range and Watershed Managment 5044-2008 74 1 2021 05 22 Investigating Vulnerability of Urban Areas to Flood Using TOPSIS Method (Case study: Azimiyeh, Karaj) Investigating Vulnerability of Urban Areas to Flood Using TOPSIS Method (Case study: Azimiyeh, Karaj) 23 36 82305 10.22059/jrwm.2020.303338.1508 FA Mina Pouresmaeel Graduate)M.Sc.( Student in Watershed Managment, Faculty of Natural Resources, University of Tehran, Karaj, Iran Ali Salajegheh Professor,Faculty of Natural Resources, University of Tehran, Karaj, Iran Arash Malekian Associate Professor, Faculty of Natural Resources, University of Tehran, Karaj, Iran Amirreza Keshtkar Assistant Professor, International Desert Research Center, University of Tehran, Karaj, Iran Journal Article 2020 05 23 The complexity of the urban environment makes it difficult to consider all the vulnerable components of the urban. Hence, decision-making in urban environments is one of the most important issues in modern management. As a result, the purpose of this study is to investigate the urban vulnerability of Azimiyeh in Karaj to flood based on multi-criteria decision-making method. The statistical population includes specialists who had sufficient knowledge and experience in the field of vulnerability management in urban areas. To this research, first, comprehensive knowledge of the factors affecting the urban vulnerability to floods was obtained using library studies, and then, the results of the Delphi technique, , was shown that among the primary indices, a total of 11 effective indicators were selected and a map of each of them was prepared using ArcGIS software. Then, the urban vulnerability to floods was calculated using the TOPSIS method. The study area was divided into 13 sub-areas based on runoff directional pattern and field observations, and then the decision matrix was made according to 13 sub-areas and 11 indicators. The results showed the vulnerability of this region to floods, which among the studied sub-areas, in sub-areas No. 1 and 2 observed the highest of flood vulnerability and the lowest of it observed in sub-area No. 13. Causes of flood vulnerability in the region include a direct connection to the upstream catchment that has lithology impermeable and geologically impermeable, high-density of building and population, and lack of proportionate open spaces. The complexity of the urban environment makes it difficult to consider all the vulnerable components of the urban. Hence, decision-making in urban environments is one of the most important issues in modern management. As a result, the purpose of this study is to investigate the urban vulnerability of Azimiyeh in Karaj to flood based on multi-criteria decision-making method. The statistical population includes specialists who had sufficient knowledge and experience in the field of vulnerability management in urban areas. To this research, first, comprehensive knowledge of the factors affecting the urban vulnerability to floods was obtained using library studies, and then, the results of the Delphi technique, , was shown that among the primary indices, a total of 11 effective indicators were selected and a map of each of them was prepared using ArcGIS software. Then, the urban vulnerability to floods was calculated using the TOPSIS method. The study area was divided into 13 sub-areas based on runoff directional pattern and field observations, and then the decision matrix was made according to 13 sub-areas and 11 indicators. The results showed the vulnerability of this region to floods, which among the studied sub-areas, in sub-areas No. 1 and 2 observed the highest of flood vulnerability and the lowest of it observed in sub-area No. 13. Causes of flood vulnerability in the region include a direct connection to the upstream catchment that has lithology impermeable and geologically impermeable, high-density of building and population, and lack of proportionate open spaces. https://jrwm.ut.ac.ir/article_82305_a93a8444da97e981baa46e5dfe42b521.pdf