The effect of human interventions on bed and right of way of Faroub Roman river and its flood characteristics

Due to the location of Iran in the arid and dry regions and flood damage in recent years, flood management studies are of great importance. The devastating effects and widespread human aggression on the riverbed of the rivers of the country have taken many forms. Therefore, simulating the hydraulic behavior of rivers is necessary to predict flood damages, flood control, river organization and other studies. In this study, the Farob Roman river of Neyshabur was modeled 2 km long. Arc-GIS software, HEC-GeoRAS and HEC-RAS software were used for river modeling and modeling was done in both construction and non-construction. In order to study the changes of river bed, the air maps of 1347 and 1398 were used and compared with each other. The sensitivity of hydraulic parameters in discharge with different return periods to changes in coefficient of Manning roughness, discharge and river slope was also investigated. The results showed the negative impact of structures on the increase in depth and area of floods due to human interference in the river flow. According to the results of the river bed determination, it has been determined that, since 1347, 40% of the river bed has been occupied by construction and the river bed has also been relocated. These interventions have increased the flooding area by 16% and increased the water level by 30%. Sensitivity analysis showed that the highest error rate of the model and the observation error was 6%, which can be seen in the appropriate accuracy of the model.