The bypass tunnel used during the construction period. The construction of the dam stopped and since then the tunnel has been leading the waters through the mountain. This tunnel was designed probably for a 20-year flood. 25 years later (approximately) a flood bigger than the design flood of the tunnel occurred and caused the overtopping and failure of the embankment used during construction. The embankment was totally eroded in one side.
Information collected during the field trip in the Sierra Nevada, as part of the "Engineering Geology" course curriculum, instructed by Professor N. Sitar, Department of Civil & Environmental Engineering, University of California at Berkeley.
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