Sediment discharge characteristics of the Three Gorges Reservoir during flood seasons

The sediment discharge during flood seasons is important to reservoir sedimentation management. By generalization theory deduction, this article analyzed the main factors affecting sediment discharge during flood seasons of the Three Gorges Reservoir. Based on measured water and sediment data, an empirical formula for the sediment discharge ratio during flood seasons of the Three Gorges Reservoir was established, and the risk of sediment accumulation under optimized flood seasons scheduling was discussed. Results showed that the incoming sediment of the Three Gorges Reservoir in flood seasons accounted for more than 90.5% of the annual incoming sediment, which was mainly concentrated during flood. The empirical formula for sediment discharge ratio during flood seasons was established. The sediment discharge ratio was influenced by both flow rate and water level, and had a good inverse relationship with the comprehensive influencing factors represented by the inflow and outflow of the reservoir and the water level in front of the dam. During flood seasons, the operation mode of “high inflow with low water level, low inflow with high water level” could be adopted to improve comprehensive benefits. This research could provide reference for sedimentation management and optimal operation of the Three Gorges Reservoir. © 2024 Science Press. All rights reserved.