Abstract:
Hypothetical dam break analysis of Hirakud dam, Odisha, India, is carried out in the present study. Dam break analysis is an important method to predict possible hypothetical dam failure modes and their consequences to prepare an emergency action plan (EAP), if it would happen. The possible dam breach failure parameters such as breach width, breach failure time, breach side slope and outflow characteristics such as maximum water level and its travel time are predicted using NWS DAMBRK equation and MIKE 11hydrodynamic mode, respectively in the downstream area up to the head of delta, Mundali. Estimated probable maximum flood (PMF) is used as reservoir inflow for probable dam breach failure along with different combinations of dam breach parameters. Outflow characteristics in the downstream river channel are generated using river cross-sections extended in the floodplain extracted from Shuttle Radar Topography Mission (SRTM) digital elevation model (DEM). Moreover, flood inundation maps are prepared in Arc-GIS tool for downstream areas using maximum water levels generated by the dam break model for flood management plan.