Evaluating Safety of Concrete Gravity Dam on Weak Rock: Scott Dam
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 126, Issue 5
Abstract
Scott Dam is owned and operated by Pacific Gas & Electric Co. (PG&E) as part of the Potter Valley Project. Although it is an unimpressive concrete gravity dam [233 m (765 ft) long with maximum water surface 33.4 m (110 ft) above tailwater], the dam has unusually complex and weak foundation rocks; this condition caused design changes during construction, numerous subsequent special investigations, and several corrections and additions. A main stumbling block to clarification of the dam safety issue for Scott Dam has always been difficulty in characterizing the foundation material. This paper discusses an approach to this problem as well as how the safety of the dam was subsequently confirmed, following a comprehensive program of research, investigations, and analysis from 1991 to 1997.
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Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 126 • Issue 5 • May 2000
Pages: 429 - 442
History
Received: Apr 5, 1999
Published online: May 1, 2000
Published in print: May 2000
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