Evaluation of sediment removal techniques in order to prolonguseful life of the dam reservoir (Case study of Sefidrud Dam)

Currently, there are more than ۵۷,۰۰۰ large dams in the world, which are usedfor water supply, irrigation, hydro power generation, flood control, inlandnavigation and recreation. As a result of annual sedimentation, ۱ - ۲ % of thetotal storage volume of these dams is lost. This issue creates the need to buildmore dams, especially in arid and semi-arid areas. Today, one of the biggestconcerns in the field of dam management and maintenance is the issue ofremoving the sediments deposited in the reservoirs of the dams. Thisphenomenon causes problems such as reducing the useful volume of thereservoir, malfunctioning of the lower valves, unreliability in the production ofhydroelectric energy and flood control, creating more force during anearthquake, environmental effects and increasing the water level of the reservoir.In this article, the types of sediment discharge methods available are describedfirst, and then, by studying Sefidroud Dam and evaluating the strengths andweaknesses of each method to remove sediment from the reservoir of this dam,the best method to perform this operation is suggested.