Page - 248 - in Book of Full Papers - Symposium Hydro Engineering

Due to the decrease of natural runoff and the increase of water demand in the downstream in storage period, the full storage ratio of the TGP reservoir with design dispatching mode is low, greatly affecting the navigation and ecological water guarantee during the dry water period. The TGP reservoir optimizes the storage process by moving up the storage time, rising the origin storage level and controlling the water level dynamically combined with the hydrological forecast. Firstly, the trend of water volume in the storage period is judged according to the long-term prediction, and the water storage scheme can be initially proposed. Also, the impounding strategy is constantly rolling and correcting according to the short-term prediction with high accuracy in the later, is concrete is: when the inflow forecast shows low, storing water in advance appropriately and making full use of the water in late flood season. If the forecast shows low continuity in the storage period, raising the water level in stages in this period, and the water level should be raised in different degrees according to the runoff reduction degree in the forecast. That is to say, the reservoir is regulated with separated methods in wet year, dry year and extreme-dry year ,and the water level in control nodes in the storage period are gradually raised on the basis of the design dispatching regulation, to ensure the completion of water storage tasks at different runoff levels. Based on the optimization strategies above, the TGP reservoir improves the operation mode with storing water in advance properly and raising the water level in stages according to the runoff forecast. The TGP reservoir has successfully stored to 175m for eight years since 2010(Fig.3). Under the implementation of this optimization method, the TGP reservoir combines the flood control and water storage work. Flood resources in late flood season are fully utilized. The water level elevation in September can increase the water storage capacity, effectively ensuring the reservoir’s full filled. Also, the reduced demand for water storage in October can greatly alleviate the impact of water storage on the downstream. Fig. 3 The storage process of the TGP reservoir from 2010 to 2017 5.2. EMERGENCY DISPATCH MANAGEMENT SYSTEM As a backbone project in the Yangtze River basin, the TGP reservoir has made many breakthroughs and contributions for emergency assistance. For instance,it 248