<P> In 1944, the United States Bureau of Reclamation head design engineer, John L. Savage, surveyed the area and drew up a dam proposal for the' Yangtze River Project' . Some 54 Chinese engineers went to the U.S. for training . The original plans called for the dam to employ a unique method for moving ships; the ships would move into locks located at the lower and upper ends of the dam and then cranes with cables would move the ships from one lock to the next . In the case of smaller water craft, groups of craft would be lifted together for efficiency . It is not known whether this solution was considered for its water - saving performance or because the engineers thought the difference in height between the river above and below the dam too great for alternative methods . Some exploration, survey, economic study, and design work was done, but the government, in the midst of the Chinese Civil War, halted work in 1947 . </P> <P> After the 1949 Communist takeover, Mao Zedong supported the project, but began the Gezhouba Dam project nearby first, and economic problems including the Great Leap Forward and the Cultural Revolution slowed progress . After the 1954 Yangtze River Floods, in 1956, Mao Zedong authored "Swimming", a poem about his fascination with a dam on the Yangtze River . In 1958, after the Hundred Flowers Campaign, some engineers who spoke out against the project were imprisoned . </P> <P> During the 1980s, the idea of a dam reemerged . The National People's Congress approved the dam in 1992: out of 2,633 delegates, 1,767 voted in favour, 177 voted against, 664 abstained, and 25 members did not vote . Construction started on December 14, 1994 . The dam was expected to be fully operational in 2009, but additional projects, such as the underground power plant with six additional generators, delayed full operation until May 2012 . The ship lift was completed in 2015 . The dam had raised the water level in the reservoir to 172.5 m (566 ft) above sea level by the end of 2008 and the designed maximum level of 175 m (574 ft) by October 2010 . </P> <P> Made of concrete and steel, the dam is 2,335 m (7,661 ft) long and the top of the dam is 185 m (607 ft) above sea level . The project used 27.2 × 10 ^ m (35.6 × 10 ^ cu yd) of concrete (mainly for the dam wall), used 463,000 T of steel (enough to build 63 Eiffel Towers), and moved about 102.6 × 10 ^ m (134.2 × 10 ^ cu yd) of earth . The concrete dam wall is 181 m (594 ft) high above the rock basis . </P>

When did the three gorges dam finished construction
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