Stochastic Risk Analysis of Urban Water Systems by Aggregation of Fault Tree and Monte Carlo Simulation

Risk assessment is so necessary part of urban water systems management as an important infrastructure. Before decision making about possible risk reduction measures, an effectiverisk assessment model should be applied to analyze different hazard events that drinking water systems, from source to tap may face them. Fault Tree Analysis (FTA) method is apowerful approach for quantitative risk assessment of complicated infrastructures such asurban water systems, but it has some limitations such as inability to consider uncertainties in incomplete data, hazards natures and experts’ knowledge. So in this paper to overcometo this limitation, this method has been aggregated by Monte Carlo Simulation (MCS)model. This method has been applied to decrease the ambiguities and uncertainties of unknown basic events by mapping stochastic problem in to many deterministic problemswhich cannot handle by traditional Fault Tree analysis. Applicability of the proposed method has been examined in Urmia City in Iran and achieved results have been explained. The results show that the proposed method can provide sufficient reliability based decision making tool for urban water systems under different water quantity and quality crises

Keywords:

Risk Analysis , Fault Tree Analysis , Monte Carlo , Uncertainty , Urban Water Supply