Map of aqueducts supplying water to Rome.
Typical cross-section of Roman aqueduct.
Typical longitudinal section of Roman aqueduct.
The Three Gorges Project centers on the construction of a hydroelectric dam on the Yangze River in central China. The Yangze is the world's third longest river, with a watershed covering 700,000 square miles, or 20% of China's land area and 25% of it's cropland. The watershed area also accounts for 33% of China's population and 40% of it's industrial capacity. The river discharges about 350 cubic miles of water per year (or 1.63 million cubic feet per second or 46,260 cubic meters per second) and transports 600 million tons of mud and silt annually. The river drops in elevation at a rate of about 6 inches per mile (or 0.09 m per km) in the Three Gorges region.
China requires additional electric power to support it's growing population and expanding industrial base. In addition, the government would like to provide for flood control on the lower reaches of the Yangze, which has experienced several extensive flooding disasters even in recent times. The Three Gorges project is designed to address these concerns. However, as the reading material below makes clear, it is by no means obvious that the project is the correct solution to either concern.
Some particulars:
History of Three Gorges Project.
Sedimentation Problems at Three Gorges Dam
Recent Chinese government report
Go to the Center for Applied Coastal Research web page for further info on coastal engineering at the University of Delaware and worldwide.
Based on information given above, and assuming that the dam height is 175 m and the width of the reservoir is the same as the width of the dam, calculate how long it will take to:
Return to James T. Kirby's home page.
Return to CACR home page.
kirby@udel.edu 
