The Yangtze River flow will be dammed at the Three Gorges for the second time in December 2002 to make way for the construction of the world's largest hydro-electric project.
The Yangtze River Water Resources Committee, designer of the Three Gorges Project, is drawing up plans and has made experiments for the second damming scheme.
To ensure normal navigation in the course of the 17-year construction period, engineers have made up a plan of using cofferdams. When the mainstreams of Yangtze River were blocked on November 8, 1997, cofferdams were built on the river's left bank to form a pit in which a dam and a powerhouse were constructed.
The aim of the current river damming is to build another powerhouse and complete the dam on the right side of the river.
The river damming will be conducted on the water diversion canal which has a length of 3.7 km and a width of 350 meters. The canal serves as the only navigable channel for ships and boats between 1997 and 2002.
China has invested 59.1 billion yuan (US$7.12 billion) in construction of the Three Gorges Project since it started in 1993. In the first phase, a diversion canal and a temporary ship lock were built. Resettlement of people living in the dam area cost 22.4 billion yuan (US$2.70 billion) in the past eight years, accounting for two fifth of the total sum.
Li Yong'an, deputy general manager of the Three Gorges Project Development Co., estimated the dynamic investment of the entire project at 180 billion yuan.