Extending the application of risk-informed dam safety decision making

The Bureau of Reclamation has been using risk analysis as the primary support for dam safety decision-making for over 15 years. The typical risk analysis conducted by Reclamation focuses on an existing dam in its current condition. Potential failure modes are identified and risks are estimated for all plausible failure modes. The risk estimates and the supporting dam safety case form the basis for decisions and prioritization of dam safety actions. As the use of risk-informed approaches has evolved at Reclamation, risk analyses have been conducted in some non-traditional ways that have allowed for more informed dam safety decisions. These areas have included: using risk analysis to assess the impact of a dam raise or a proposed change in reservoir operations; using risk analysis to evaluate the adequacy of a new design; using risk analysis to evaluate the current and future conditions of a concrete dam that is deteriorating; and, using risk analysis to evaluate the dam safety impacts of oil and gas exploration at existing reservoirs.