Engineering geological problems in the Three Gorges Project on the Yangtze, China

The Three Gorges Project formally commenced in December 1994. Geological investigations, however, have been in progress since the 1950s. The scope of this work was comprehensive, covering all aspects of reservoir geology, regional tectonics and seismicity, as well as studies related to site selection and structural foundation conditions and construction materials. In this paper a review of the geological studies is conducted with emphasis placed on the principle geological problems. The following is concluded: the damsite offers an excellent foundation in Precambrian granite rocks; the tectonic setting for the project is relatively simple; the existing level of seismicity is anticipated to remain at the same low level; no significant change in the stability of existing bank slopes is expected to occur due to the operation of the reservoir; and no slides will endanger the construction and operation of the project.