Darbandikhan Dam Collapse Scenario and Its Impact on the Areas Along the Diyala River Basin Down to the Hamrin Dam

Abstract

The study and preparation of dam collapse scenarios is one of the basic things that must be ready for the purpose of preparing emergency plans to confront such collapses in order to spare the population and infrastructure the resulting losses and reduce their impact. In this study, we dealt with the possibility of collapsing the Darbandikhan Dam and its impact on the areas along the Diyala River Basin and on the integrity of the Hamrin Dam, using advanced hydrological modeling software and geographic information systems for the purpose of calculation and display. The hydrological modeling program (WMS9.1), which includes the simplified mathematical modeling of dam collapse (SMPDBK91), was used, and the digital elevation model for the region was used as a basis for preparing the cross-sections along the river and as one of the basic inputs in calculating the mathematical model and then preparing the inundation maps. The results of the mathematical modeling showed that the maximum depth of the flood water near the wall of the Hamrin Dam body at the levels (471 and 485) meters above sea level, is about (5.6, 6.3) meters, respectively. It was found that the collapse of the Darbandikhan Dam had no effect on the safety of the Hamrin Dam as long as the water level in the Hamrin Lake reservoir and the proximity of the dam’s body did not exceed (100.7) meters above sea level, at the time of the hypothetical collapse of the Darbandikhan Dam.