Author(s): W. R. Fiedler

Linked Author(s):

Keywords: Hydraulic Structures; Risk; Dam Safety; Modification

Abstract: The Bureau of Reclamation’s Dam Safety Program manages risk for over 300 high and significant hazard dams.When risk estimates for potential failure modes indicate increasing justification to take action to reduce risk, dam safety recommendations are typically made. The dam safety recommendations can focus on collecting additional data/performing studies to better quantify risk or on initiating corrective actions to address well defined risks. Dam safety recommendations within Reclamation’s inventory address a number of different issues, such as those related to internal erosion, flood overtopping of dams and seismic stability of dams. Dam safety recommendations related to hydraulic structure potential failure modes also represent a significant portion of the recommendations withinReclamation’s inventory. This paper will focus on the methodology used to estimate risks for hydraulic structure potential failure modes and will summarize the relative contribution of the risk posed by hydraulic structures to the overall risk within Reclamation’s inventory of dams. Potential failure modes related to hydraulic structures include overtopping of chute walls, stagnation pressure failure of spillway chute slabs, cavitation damage of concrete flow surfaces leading to loss of concrete lining, structural failure of spillway gates and erosion of the foundation and scour and head cutting in the downstream channel or dam/spillway foundations. The paper also includes examples of dam safety modifications related to hydraulic structure potential failure modes.

DOI: https://doi.org/10.15142/T3720628160853

Year: 2016