Investigation of sediments deposition in streams and its impact on the volume of reservoir

Gabions are one of simple methods of control erosion and flood and reducing of flood damages. Field survey show behind most of the gabions is filled by coarse sediment and debris. Therefore, in this study the role of these dams for maintenance of sediment was investigated. To conduct this 16 gabions on Zidasth, Taleghan were selected. Sampling was conducted from 0-50cm depth on the deposition sediment in the gabions. Correlation analysis by SPSS software between area and volume dam was conducted. For this were estimated of mead diameter, D50, D95, Sorting percentage of provincial flower and the percentage of sand and gravel. The analysis sediment gradation curve was show much of the sediments deposited in the dams are coarse and so, they are located in the range sand to gravel. The results were show only correlation of the volume and mud was significant. Others factors has not significantly correlation with dams area and volume. So, the location of dams should be selected so that cause coarse sediments sedimentation is in the natural stream. In addition, dam reservoir volume is large. This cause a calm flow and fine sediments deposition.