Estimating Reservoir Sedimentation at Large Dams in India

Abstract

Mathematical expressions are developed that relate the storage capacity loss of reservoirs in India to the catchment area, the reservoir surface area, the original storage volume, and the time since the first filling of the impoundment. The relations for sedimentation of reservoirs found on eastward and westward flowing rivers differ significantly, because of meteorological and geological influences on land surface runoff and sediment yield within reservoir catchments. The formulations give good fits to the assembled data and allow an uncomplicated calculation of the half-life of reservoirs (that is, the time needed for the storage capacity to be reduced by 50%), which offers a measure of when sedimentation will have a significant adverse impact on the functioning of dams.