Evaluation of Lesser Zab River Course Change between Dokan and Dibbs Dams (N-Iraq), Using GIS Techniques

Abstract

The morphology of the lesser Zab River is influenced, by the presence of two dams (Dokan dam and Dibbs dam) that regulates the natural seasonal flows, this will affect the study area infrastructure and it has varied impacts upon water management strategies. Therefore, this study aims to quantify the morphological changes of the river course in the downstream reaches of the Dokan dam using Remote Sensing and GIS techniques using the Digital Elevation Model (DEM 30x30m) for the period from 1980 to 2020. This study shows that the differences in discharge for a long time will affect the distribution of erosion and deposition along the downstream river channel. The river course has been changed slightly at the upper reach of the study area, and the overall change is towards the middle and the lower reaches of the river, showing a gradual increase in the channel length, increasing meandering index, and the formation of alluvium islands at the river meander. Implications of this study could help identify river changes and their influence on the design and planning of water management projects and infrastructure in the area beside the other risks that might arise in terms of hazards such as floods.