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About Dams

Back to designDesigning Dams - Geologists

Engineering geologists investigate the geology of the dam site and the area to be occupied by the reservoir. They provide an overall picture of the types of soils and rocks below the earth's surface, their thickness and the directions in which they slope. They assess the quality of the ground to determine whether leakage of water from the reservoir could occur.

For embankment dams, geologists investigate nearby areas where natural materials can be excavated for their construction.

The Shihkhang Dam Ruptured by the Chi-Chi Earthquake

The Shihkhang Dam Ruptured by the
Chi-Chi Earthquake, Tiwan in 1999

Engineering geologists also consider whether the site of the proposed dam is in a region where earthquakes can occur. They look for the presence of any faults in the rocks and consider whether an earthquake could cause the fault to rupture. During the 1999 Chi-Chi Earthquake in Taiwan, the movement of a fault below the Shihkhang Dam actually broke the dam in two.