ABSTRACT
It has been estimated that the average annual sediment inflow to the Tarbela Reservoir has been about 203 million tonnes since the construction of the dam and that 95% of this settles into the reservoir. Due to this massive settlement of the sediments the reservoirs has lost about 32% of its gross storage capacity. The high sediment inflow to the reservoir, the reservoir operation policy and the sedimentation pattern in the reservoir has created a huge sediment delta in the reservoir. The delta was moving towards the dam at a rate of approximately 0.5 km per year up to 2003. Since then the delta’s forward movement is almost stagnant. It might be due to the adoption of reservoir operation policy of raising minimum operational water level to a height of 417.3 m+MSL from 396.2 m+MSL. The sediment delta has reached now at a distance of 10.5 km from the dam.
