During the risk evaluation process, engineers commonly use the
traditional or risk-based dam safety assessment approaches. Traditional
methods evaluate risk based on the factor of safety without
defining any level of confidence (Bowles et al. 1997). Unlike traditional
methods, risk-based dam safety approaches consider the likelihood
of a failure, which is a more efficient way for reducing risks
where there are limited financial resources (Bowles et al. 1998).
Risk-based approaches identify the risk level based on the estimation
of failure probability and possible consequences in the event
of a failure. Different methodologies, such as event tree analysis
and probabilistic analysis, are applicable to identify the risk levels.