Estimation of sediment produced from the middle of the field contour Karoon3 and shahid Abbaspoor Dam using model GSTARS3

Surface runoff and water flow in rivers are always accompanied by soil erosion and sediment transport. Water is one of the most important causes of erosion of the earth's crust and in its path carries materials in solution, suspended and bed load. These materials settle wherever the right conditions require. The presence of these substances in water is very important for drinking, industrial exploitation, agriculture, aquaculture, creating dead volume of dam reservoirs, sedimentation of canals, reducing the capacity of rivers and canals, as well as flood control. These materials are washed from the slopes and plains and cause soil erosion and poor vegetation and environmental degradation.

Trapping efficiency shows the percentage of sediment material entering the reservoir that settles. Trapping efficiency is a function of the ratio of tank volume to annual inlet water volume:- The volume of Shahid Abbaspour Dam reservoir has been estimated at 3 billion cubic meters according to previous studies.- According to the statistics and information of Khuzestan Water and Electricity Organization, the average discharge rate of Karun 3 dam station in the period 1977 to 1999 is equal to 359 cubic meters per second, which the average annual input volume is 11321424000 cubic meters. Therefore, the ratio of reservoir volume to annual inlet water volume is 0.26 , which by extracting the result, trapping coefficients for fine-grained, medium-grained and coarse-grained sediments are 88%, 95% and 98%, respectively, the average total trapping coefficient. 94% sediments have been obtained.