Investigation of hydromorphological changes of river corridor using satellite images

In Iran during five decades ago, flood is the most prevalent disaster that threatened more than 80% of cities area. In this research, using remote sensing methods, Google Earth satellite images, and GPSVisualizer Internet system by producing multiple maps in ArcGIS and AutoCAD software environment and using the method of overlaying, the hydromorphological changes of Tajan River during floods and the effects of hydraulic structures in the river corridor on erosion and sedimentation phenomena were identified. The results showed that due to the intensity and strength of the flood flow, erosion was the predominant phenomenon in the study area and the most severe erosion occurred in segment No. 2 (the second kilometer of the study area includes the most of hydraulic structures). Also, Tajan Bridge as an intersection structure and Drop No. 4 as a parallel flow structure were the most important structures that had the greatest impact on the river’s hydromorphological changes in terms of erosion. Finally, the evaluation of the accuracy of the modeling results with the facts that occurred in nature (recorded by multiple field visits) indicated that the results were in good agreement with the facts that occurred in the study area (about 80% of the results corresponded to the facts that occurred in nature). Thus, the Google Earth Pro satellite images in a short time and at the lowest cost, have the ability to measure and identify hydromorphological changes caused by river floods. This method can be favored by city and regional managers and policymakers.