Hydraulic Simulation of the Failure of the Embankment Dams: (Part 2: Risk Analysis and Identifying of Vulnerable Points)

In the first part of this study, hydraulic modeling of failure of the Tabarakabad and Cahcahe dams in Khorasan Razavi province was analyzed and discussed. In the second part, the consequences of the failure of these two dams will be examined. In order to assess the risk, a method based on descriptive-analytical (quantitative-qualitative) approaches has been proposed and a questionnaire has been prepared in this regard. Risk assessment and analysis of these dams in the proposed method, which is consistent with passive defense approaches, was implemented with the help of experts in this field and with the help of a coded program. Finally, for different scenarios such as overtopping, piping and sudden failures (subversive actions), assets valuation of downstream dams, threats, vulnerabilities, risk zoning maps and drafting of emergency action plan is presented. According to the results, it was indicated that the risk of the Tabarakabad dam is higher than Cahcahe dam and in case of an accident, the villages adjacent to the dam and the city of Quchan will suffer serious damage. However, the correct operation of the Cahcahe dam overtopping can play an important role in stabilizing and preventing the occurrence of crisis.