干旱区生态环境知识资源中心

Using floodwater in and and semi and areas of Iran is important especially in the recent years. Using lateral intake is a method of floodwater diverting. In and and semi-arid areas, floodwater has large amount of sediment that will be carried into the intakes and decreases the channel conveyance. There are several methods of sediment control in lateral intakes. Most of these methods are used in permanent river and irrigation canals. In this investigation using sill for sediment control in lateral intakes has been studied. Also the amount of sediment inclusion into the intake and pattern of sedimentation has been analyzed.

Experiments have been conducted for a 60 degree intake channel. Slope and width of main channel, width of lateral channel and bed material of main channel are constant in all experiments. For the selected bed material, there is only bed load sediment transport. Experiments have been done for three discharges and three depths for each discharge. The volume of sediment entered into the lateral channel and the volume of sediment transported in main channel have been measured. The pattern of sedimentation has been determined using bed topography. It was found that the volume of sediment transported into the lateral channel and the width of sedimentation area decrease with using sill.