Determination of Sediment Volumes in Dams with Hydrographic Surveys

Loss of capacity of dams consists as a result of the accumulation of sediment carried by rivers. This loss causes the shortening of the economic life of dams. Before construction of dams, preventive measurements should be taken into account during watershed planning and it is necessary to calculate the amount of sediment by measuring hydrographic surveys at given intervals in dam. In this study, by utilizing hydrographic maps made in 1972, 1982 and 2013, the amount of sediment was calculated. In calculations, softwares which were Netcad5.1, Global Mapper and PDS200 were used. 50-year the amount of sediment calculated by DSI in 1968 was estimated as 3.77 hm^3. According this estimate, 45-year the amount of sediment was calculated as 3,49 hm^3. In the 45-year period, according used software, the amount of sediment are changing between 4.255 hm^3 and 4.383 hm^3. The amounts of sediment calculated with different softwares are compatible with each other at rate of %97. It is considering that 50-year the amount of sediment is 3.77 hm^3 after completions of dam construction, it is in question that the comparison made by average of different softwares is compatible at rate of %78.