Dam break studies

Abstract

Dam provides a very vital role in the economy of a country by providing numerous benefits such as water supply, hydropower, irrigation and flood control. However, in the event of dam failure, which is almost catastrophic failure causes significant life losses and property damages. It is important to classify hazard potential due to dam failure as Low Hazard and High Hazard. This is done based on potential of death, destruction of properties and vital resources. The proposed Bakun Dam in this study has been classified as a Low Hazard Dam. This study area covers about 175 km downstream of the dam. Dam break analysis was carried out using NSW FLDWAV computer model. The purpose of this study is to determine the impact of dam failure to the downstream area and to establish Emergency Action Plan, EAPs for the vulnerable area. Dam break modeling was done for two modes of dam failure, namely overtopping failure and piping failure. The breach parameter of possible worst case scenario, considered in the study. The result shows that the peak discharge due to overtopping failure is 47,531 m3s-1 with possible maximum velocity of 21.83ms-1. The peak discharge due to piping failure is 33,192 m3s-1 and the maximum velocity of 19.7 ms-1. The result indicated that impact of breach outflow to the downstream area is less significant.