Dam Site Identification Using Remote Sensing and GIS (A case study Diamer Basha Dam Site)

Selection of suitable sites for construction of dam is the most important phase because a number of factors are required to consider that include topography, geology, tectonic settlements and the slope. We selected Diamer Basha dam site to analyze it feasibility considering real-time field data. Geologically the study site is a part of Chilas Mafic Igneous Complex which is not ophiolite. Matic complex is a block which is 40km in depth and 300km in length. These rocks are comparatively hard in nature and are considered good for construction of dam. Tectonically, we observed that the area under investigation was highly active tectonically. Surface deformation rates of the study site are highest throughout the world because this area is comprised of multiple fault lines that include Main Mantle Thurst (MMT), Main Karakoram Thrurst (MKT), Main Boundary Thurst (MBT) and many others. This area has become a hot cake for the geologist worldwide due to it’s very high surface deformation rates.Tectonically active regions are considered worst for construction sites, e.g., for dam sites. The dam site is actcually laying on the MKT which is not favorable for construction of Diamir Basha dam. A low-level earthquake may generate small cracks in concrete structure and any leakage of water may produce big holes with passage of time which are not remidable. A big level earthquake may vanish the dam site completely. Therefore, the current site is not favorable for construction of dam.