Recent events in New Orleans have shown the magnitude of life loss and property damage that can occur due to the failure of man-made levees. The California Bay Delta and Sacramento levee systems in California pose a similar or greater level of risk to life and property. In order to effectively mitigate the hazard associated with levee failure a systematic evaluation of risk must be carried out. This paper presents preliminary research into the risk associated with the California Bay Delta. A comprehensive list of failure modes for man-made levees is presented. Preliminary empirical data on the temporal frequency of failure and the consequences of failure in the Bay Delta has been compiled. Also presented is the frequency of high water conditions, frequency of strong ground shaking, and a discussion of possible correlation of failure with these loading conditions. Based on preliminary empirical data, the distribution of the risk function is estimated using Monte Carlo simulations. The general objectives of this paper are to present an approach to levee risk analysis for the California Bay Delta, stimulate discussion, outline the data gaps that exist, and push for continued research on mitigating this hazard.
Civil and Environmental Engineering