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����With a vast territory�� China is rich in water resources. However�� the spatial and temporal distribution of water resources is uneven due to the integrated impacts of climate�� topography�� and other factors. Specifically�� precipitation decreases from south to north. The interannual variation of yearly precipitation is significant. Frequent floods and droughts occurred and observed. Since 1949�� many conservation and hydropower engineering project�� eg. �� water storage�� diversion�� and transfer projects have been constructed�� which greatly contribut to the economic and social development. Currently�� higher requirements have been put forward for water conservancy projects to support a sustainable��rapid socio-economic development�� as well as the strategic needs of building a moderately prosperous society in an all-round way. In 2014�� the State Council arranged 172 major water conservancy projects for water saving and water supply�� providing new opportunities for water conservancy construction.����China is rich in hydraulic China is the world's largest producer of hydroelectricity. In the mainland�� the potential annual hydroelectric power is 6.08 trillion kW . h�� the average power is 694 million kW; technical developable installed capacity is 542 million kW�� annual power generation is 2. 47 trillion kW��h;economically developable installed capacity is 402 million kW�� annual power generation is 1.75 trillion kW��h.Presently in China�� the installed capacity of hydropower is over 230 million kW�� ranking first in the world. Hydropower��as a renewable clean energy�� has the characteristics of mature technology�� low cost��flexible operation and so on. Most countries in the world give priorities to hydropower development in energy construction. Meanwhile�� China leads the world in renewable-energy production mainly from hydropower. Hydropower has made significant contributions in many aspects�� For example�� it helps to adjust the energy and power structure�� reduce greenhouse gas emission�� miti gate the climate and environment�� and socio-economic development. There-fore�� hydropower is listed in the key areas of energy development and renewable energy development in China.