Interpretation of the sedimentation process in the proposed sand trap of the Cerro del Aguila dam

According to the ISI Program (International Sediment Initiative), it is mentioned that erosion and sedimentation processes in the management of water bodies, such as the Cerro del Aguila reservoir, is a very important issue on a worldwide scale from a social, economic and environmental point of view [1]. The desander projected for the Cerro del Aguila reservoir is a large-scale one that would provide an important improvement in the management and care of the dam's infrastructure. With the proposed improvement of the geometry of the proposed desander for the Cerro del Aguila dam, it is expected to obtain a considerable optimization in the operation and projected efficiency of the sand trap, as well as with respect to the operating flow requirement of the turbine of the power plant, which is one of the weak points of the initial proposed design. The verification of the functionality of the proposed improvement evidences as a consequence, the opportunity of implementing a "Flushing"type washing system with Bieri type purge gates, which results in a second advantage offered by the improvement regarding the optimization of the operation in general. As numerical results of the modeling considering a particle size of 0.5 mm, we have, on the one hand, a velocity of 0.11 m/s (low velocities), and on the other hand, that the amount of sediments deposited in a year within the 3 vessels for a flow rate of 70 m3/s is a total volume of 0.01 Hm3, without decreasing the operational flow of the turbine. This large amount of sediments can be removed automatically and efficiently, reducing plant shutdowns for maintenance, operating costs and losses due to power outages, as well as extending the useful life of the expensive electromechanical installations.