A Framework for Quantitative Risk Analysis of Damsy

While there is consensus that a quantitative risk assessment (QRA) is the highest level of risk analysis for dam safety, a detailed definition and framework for a QRA is not described in available guidance documents. We propose a definition for a QRA and describe the attributes that distinguish it from other types of risk analysis. In particular, we believe that a QRA should (1) prioritize the use of engineering models and methods over estimates that are largely based on subjective judgements of experts to develop inputs to the risk analysis; (2) employ structured interaction among experts to achieve a well-documented risk analysis that captures the center, body, and range of technically defensible interpretations of data, models, and methods used in the risk analysis; and (3) have a clearly defined framework for identifying and evaluating sources of randomness and uncertainty in data, methods, and models used in the risk analysis.