Ranking of the Siah Cheshmeh drainage basin in terms of flooding to manage flood hazards

The present study investigates and analyzes the role of hydrogeomorphic parameters in flood susceptibility of sub-basins of the Siah Cheshmeh basin located in West Azerbaijan province. For this purpose, first, the study area was divided into 6 sub-basins based on topographic and drainage characteristics using a digital elevation model (DEM) with a spatial resolution of 12.5 m. In the next step, 8 hydrogeomorphic parameters including Stream order, Streams length, Drainage density, Compactness coefficient, Circularity ratio, Form factor, Basin relief and Ruggedness number were prepared using Horton, Schumm, and Strahler geomorphological rules in ArcGIS software. Then, to weight the parameters, the SWARA multi criteria decision-making method was used, and the relative weight of each of the eight parameters was determined for the 6 studied sub-basins. The results of weighting and prioritization showed that sub-basins 2 and 4 with the weight of 0.276 and 0.250, respectively, have the highest weight and have very high flood susceptibility. In contrast, sub-basins 3, and 5 with weights of 0.105, and 0.061, respectively, had the lowest weights in terms of 8 parameters, and therefore, in terms of Flood susceptibility is very low in the class. The total area of the sub-basins that are in high and very high classes (sub-basins 2, and 4) is about 327 Km2, which includes 33.8% of the total area of the basin.