Comprehensive Analysis and Study of Dynamic Control on Water Level of Sanmenxia Reservoir in Flood Season

摘要

305 m of limited water level for Sanmenxia Reservoir during flood season was set up under a specific historical condition. If a fixed water level is adopted for the whole flood season, it will evidently not be a scientific way to deal with the relationship among flood control, sedimentation reduction and benefit making. Over the last ten years, the flooding water running into the Reservoir has been greatly reduced, the flow discharge capacity at low level has raised and the elevation of Tongguan kept at high level. As a result of initial operation of the Xiaolangdi Reservoir, the boundary conditions for operation of Sanmenxia has been remarkably altered, so its limited water level shall be dynamically controlled. In compliance with importance of control principles, the priority shall be arranged as flood control and sedimentation reduction. If a 2,000 m~3/s of flood is forecasted, the Reservoir level shall be further lowered to 294 m early to strengthen the capacity in sediment delivery by flood water. When sediment content is more than 80 kg/m~3, the Reservoir can flush sediment without control or under control. It will be operated at the level of 307 m in normal time of main flood period (July and August) which will be raised to 313 gradually from early September to October 10. Then, not only the requirement of flood control can be satisfied, but also beneficial to sedimentation reduction by the Reservoir, in the meantime, it is of far reaching significance in increase of water resource utilization rate and exploiting its multi-benefit into the full.