New Procedure to Reservoir Depth and Islands Mapping for Badush Dam Reservoir Using DEM, Mosul, Northern Iraq

To determine the depths in water bodies as in the rivers, lakes, and dams reservoirs, it is necessary to use a bathometric survey, which sometimes requires cost and fieldwork, but in this study, the gradient in the depth of the Badush Dam Lake was estimated before the filling and real operation of the reservoir and found using a digital elevation model (DEM) with a resolution of 10*10 meters, where the obtained data was processed, the depth maps will be a data base for future depth monitoring, from the digital elevation (DEM) model using several programs (Global Mapper 18 & Global Mapper Pro.V.24) (Excel software), and after processing, depth maps are drawn using the (Surfer.16) software, it was noticed the increase in depth with increasing level, as the values represent the negative depths of the dam reservoir, where the minimum depth at the level of 228 m(a.s.l) ranges between (0 to -2.1 m), while at the maximum operational level at a level of 250 m(a.s.l), the depth ranges between (0 to -26 m), while at the maximum flood level of 312 m(a.s.l), the depth ranges between (0 to -90 m). As for the positive values, they represent the positive areas that fluctuate with the increase in the level due to the expansion of the reservoir area, the submergence of islands, and the emergence of new islands inside the body of the reservoir, where the lowest height was reach (0.7 m) at a level of 228 m(a.s.l), and the highest height was (35 m) at a level of 270 m(a.s.l).