Desilting efficiency improvement using a dredged channel in a reservoir

The core problem of reservoir sediment management lies in using desilting facilities to effectively remove or reduce sediment entering the reservoir, reduce reservoir silting, and ensure a stable water supply. The feasible strategies are mainly divided into hydraulic sand removal and mechanical dredging. However, the benefits of hydraulic sand removal can be increased by utilizing mechanical dredging, which can achieve complementary effects. Therefore, this study considers the bottom dredged channel formed by mechanical dredging, including different dredged channel lengths and reservoir water level scenarios. It intends to concentrate and increase the turbid water body that reaches the desilting tunnel entrance in front of the dam, thereby increasing sediment desilting efficiency. In this study, the Two-dimensional layer-averaged model (TDLAM) was used as a simulation tool to investigate the inflowing turbid water in the case of reservoirs with a bottom dredged channel. According to the simulation results of the TDLAM model, this study preliminarily found that the more extended the bottom dredged channel, the greater the sediment desilting efficiency. However, the change in water level will not significantly affect the sediment desilting efficiency.