Location

New York, New York

Session Start Date

4-13-2004

Session End Date

4-17-2004

Abstract

Lake Storey Embankment Dam originally built in 1929 to provide water for steam locomotives. This 133-acre public lake is located near Galesburg in Knox County, Illinois. The dam is a zoned embankment (with clay cores on each side of a concrete core wall, 12 inches thick), 51 ft high above the streambed, approximately 850 ft long, with a concrete free ogee spillway. Numerous minor to moderate damaged spots including a moderate size downstream slope failure have been detected during the dam inspection of Year 2000. This paper discusses the results of the investigation to identify the problems and the proposed solutions to improve the dam safety. In authors’ opinion, the failed slopes resulted from decomposition of the roots of several grown trees previously cut-down. Dealing with grown trees on embankment dams has been an environmental and safety challenge on other embankment dams nationwide. A new idea is proposed for similar situations to avoid introduction of risk of piping or slope failure due to root decomposition, if the trees on the dam or abutments are already mature. An occasionally wet downstream toe was another concern on the Lake Storey Dam. A stage construction of dam modification, and a new drainage system at the downstream toe (also serving as a shear key), are designed and are under construction at the moment. This system is expected to improve the shear strength and reduce the piping/slope failure potential by safely collecting the seepage water.

Department(s)

Civil, Architectural and Environmental Engineering

Appears In

International Conference on Case Histories in Geotechnical Engineering

Meeting Name

Fifth Conference

Publisher

University of Missouri--Rolla

Publication Date

4-13-2004

Document Version

Final Version

Rights

© 2004 University of Missouri--Rolla, All rights reserved.

Document Type

Article - Conference proceedings

File Type

text

Language

English

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Apr 13th, 12:00 AM Apr 17th, 12:00 AM

Slope Failure and Piping Potential Due to Root Decomposition in an Aged Embankment Dam

New York, New York

Lake Storey Embankment Dam originally built in 1929 to provide water for steam locomotives. This 133-acre public lake is located near Galesburg in Knox County, Illinois. The dam is a zoned embankment (with clay cores on each side of a concrete core wall, 12 inches thick), 51 ft high above the streambed, approximately 850 ft long, with a concrete free ogee spillway. Numerous minor to moderate damaged spots including a moderate size downstream slope failure have been detected during the dam inspection of Year 2000. This paper discusses the results of the investigation to identify the problems and the proposed solutions to improve the dam safety. In authors’ opinion, the failed slopes resulted from decomposition of the roots of several grown trees previously cut-down. Dealing with grown trees on embankment dams has been an environmental and safety challenge on other embankment dams nationwide. A new idea is proposed for similar situations to avoid introduction of risk of piping or slope failure due to root decomposition, if the trees on the dam or abutments are already mature. An occasionally wet downstream toe was another concern on the Lake Storey Dam. A stage construction of dam modification, and a new drainage system at the downstream toe (also serving as a shear key), are designed and are under construction at the moment. This system is expected to improve the shear strength and reduce the piping/slope failure potential by safely collecting the seepage water.