The Penstock Puzzle

by David K. Rogers, P.E., Proj. Mgr.; Harza Engrg. Co., Concord, CA,
Christopher J. Moffitt, P.E., Principal Civil Engineer; Sacramento Municipal Utility District,
Daniel L. Wade, P.E., Sr. Engr.; Harza Engrg. Co.,
Richard E. Goodman, P.E., Consultant; Mendocino, CA,
Richard C. Harlan, P.E., Consultant; San Francisco, CA,
Ron Hall, District Mgr.; Layne Christensen Co., Salt Lake City, UT,

Serial Information: Civil Engineering—ASCE, 2000, Vol. 70, Issue 11, Pg. 52-57

Document Type: Feature article


After 40 years of chronic slope movements and several engineering studies, the Sacramento Municipal Utility District in California signed a design-build contract to stabilize the 1,500 ft (460 m) long Camino Penstock, on the bank of the American River. The selected stabilization system consists of a grouted gravity structure along the lower 250 ft (76 m) of the west side of the penstock, constructed by grouting and doweling the in-place bedrock. The toppling movement was stabilized by tying the gravity structure and upslope bedrock with 400 kip (1,800 kN) tendon anchors spaced approximately 10 ft (3 m) apart and reaching about 120 ft (37 m) into the bedrock. Additionally, anchor blocks were added to three of the ring-girder foundations to stabilize downslope sliding movements.

Subject Headings: River bank stabilization | Conduits | Bedrock | Structural stability | Landslides | Grouting | Anchors

Services: Buy this book/Buy this article


Return to search