Seite - 242 - in Book of Full Papers - Symposium Hydro Engineering

STUDY ON THE INFLUENCE OF CLIMATE CHANGE ON THE THREE GORGES RESERVOIR AND ITS COUNTERMEASURES WANG FANGFANG BAO ZHENGFENG China Three Gorges Corporation, Yichang, China CHINA 1. INTRODUCTION The TGP reservoir is the key project in the Yangtze River basin, with the benefits of flood control, power generation, navigation, water supply etc.. As an important part of the flood control system in the Yangtze River basin and power supply station for power grid security, the TGP reservoir plays an important role in the economic development of the Yangtze River basin and the whole China. As a critical backbone project for the control of the Yangtze River and harnessing of its water resources, the TGP reservoir is located at Sandouping of Yichang, Hubei Province with a controlled area of 1 10^6 km2, a normal water level of 175m and an accommodation capacity of 16,500 million m3. The project has experienced the stages from the preliminary design, the initial operation to the formal operation. It stored water level to 135m in June 2003 and hence entered the period of power generation. In 2008, the TGP reservoir started 175m experimental storage 5 years ahead of schedule, and firstly stored water level to 175m in 2010. Few years later the reservoir entered the formal operation period in 2016. The climate change definitely cause the change of precipitation in the basin, which indirectly affects the total runoff and its annual distribution in this area. Corresponding to the obvious change of precipitation in the upper reaches of Yangtze River, the inflow of the TGP reservoir has also been affected, which shows that the inflow has a decreasing trend in the total year, while in the annual distribution, it increased in the dry period and decreased in the flood season and the storage period. To sum up, with the climate change in the upper reaches of Yangtze River, the hydrologic characteristics of inflow series of the TGP reservoir have changed to a certain extent. It’s necessary to make quantitative analysis on the impact of climate change, and deeply research the change regular of precipitation and runoff, and put forward countermeasures from technical aspect and management aspect, to guide the TGP reservoir to give full play to its comprehensive benefits more effectively. 2. THE ORIGINAL DESIGN DISPATCHING RULE OF THE TGP RESERVOIR 242