Dam Safety Risk Assessment (Case Study: Flood Risk for Golestan Dam)

Document Type : Research Article


1 M.Sc., Faculty of Environment, University of Tehran

2 Associate Professor, Faculty of Environment, University of Tehran

3 Associate Professor, Faculty of Civil Engineering, University of Tehran


In dam construction industry, the safety of dam is one of the most important challenges that should be
considered in design, construction and operation phase. Recently, use of quantitative risk analysis, as
a useful tool in dam safety risk management, is rapidly increasing. In this paper, first, risk assessment
methods in dam safety are investigated and australian national committee on large dams (ANCOLD)
guideline for dam safety risk assessment is detailed. Then, as a case study, safety of Goleastan dam,
in northeast of Iran, is assessed considering risk analysis approach for upstream flood hazard. For
calculating the probability of failure of dam, the various methods were assessed and finally event tree
analysis (ETA), as most commonly method in dam safety risk analysis was used. The number of life
losses due to flooding of Golestan dam break is estimated based on united states bureau of reclamation
(USBR) methodology, known as DSO-99-06. Finally, according to calculated risk and comparing with
different criteria for acceptable risk, it is obvious that the risk of Golestan dam break due to upstream
flood is unacceptable and immediate risk reduction measures are necessary.


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