In June 2003, the Three Gorges Dam opened and a reservoir the size of lake Superior began to form, inundating 372 miles of China's Yangtze River Valley. As 1,500 cities, towns and villages disappeared beneath the dark waters, more than a million people were being moved. Around the reservoir, huge construction projects are still transforming the landscape; mighty dikes, long bridges, apartment towers, and sprawling cities are springing up. Between...