PORTFOLIO RISK ASSESSMENT：A TOOL FOR DAM SAFETY RISK MANAGEMENT

ABSTRACT
Dam owners, engineers and regulators who are responsible for the safety of groups of dams need
to prioritize dam safety evaluations or funding for structural and non-structural risk reduction
measures. Traditionally “downstream hazard” assessment, weighting schemes, and judgement
have been used for this purpose. However, these have significant weaknesses and cannot be
relied on to provide the basis for an effective and efficient program for managing and reducing
dam safety risks. This paper describes the Portfolio Risk Assessment (PRA) approach, which the
authors have developed and applied to several portfolios of dams. The approach is a tool for
prioritizing risk reduction measures and additional evaluations. In addition, it provides valuable
inputs to various business processes and for strengthening other aspects of a dam safety program.
Significantly more cost effective and rapid rates of risk reduction may be achieved using this
approach.