A new methodology for estimating the areas of erosion and sedimentation in the Duhok Dam reservoir using pre-storage for geometric analysis and bathymetric survey

This study included estimating the accumulated sediments in the Duhok Dam reservoir since its inception until now. These sediments, in turn, affect the volume of water storage in the reservoir over time. The study aims to propose appropriate solutions to address these sediments with the goal of extending the operational lifespan of the dam. To achieve this, the accumulated and transported sediments were estimated in selected sections of the dam reservoir. The bathymetric survey was conducted using the (ADCP) device, and these sections were drawn by comparing the bottom of the reservoir taken from the geometric survey before the dam construction with the current reservoir bottom taken from the bathymetric survey. This aimed to determine the thickness of the sediments and their spatial distribution in the reservoir, And the erosion occurring on its banks, The findings indicate that sediment increases proportionally with water flow from the upper part of the reservoir towards the dam body. Sediment thickness starts at (3 m) at the upper part of the reservoir and gradually increases, reaching its peak at the dam body with a thickness of (19 m). Erosion from the reservoir banks varies but generally inversely correlates with sediment deposition. It is higher at the upper part of the reservoir and decreases near the dam body. The volume of accumulated sediment in the reservoir reached at the levels (599.76 m), (600.46 m), it is (3,117,032 m3). As for the volume of erosion from the reservoir's banks at the same levels, it is (2,488,153 m3).