Page 12 - jdrogers2017ab
P. 12

• As the left side of the main dam was undercut, the middle

          monolith tilted slightly and rotated, allowing water to enter

          the shrinkage crack along the west side of Block 1


     • This triggered a chain-reaction failure of the right abutment,

          after the reservoir level had dropped 70 to 80 feet.
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