USACE sets new safety standards at Isabella Lake dam, California

The US Army Corps of Engineers (USACE) is undertaking major safety modifications to the Isabella dam on the Kern river in California, which has been identified as one of the highest-risk category among the USACE’s risk guideline criteria. This means there are compelling reasons to address dam safety issues. A screening-level risk assessment process in 2005 determined that the main and auxiliary dams posed unacceptable risk. Subsequent detailed studies in 2006 and 2007 confirmed significant seismic, hydrologic, and seepage deficiencies, which could in the case of dam failure threaten the lives of downstream communities. Martin Burdett at H&D spoke to Stephen Martinez, Programme Manager for the project, and engineering technical lead Mike Ruthford, about the project, which is designed to address the risk of failure as a result of an earthquake, overtopping of the dam or seepage and piping.