Study of dam break analysis using HEC-RAS

Abstract

Dams are considered as structures containing dangerous forces. Even though dam failures are comparatively rare, they can cause immense damage and loss of life and properties when they occur. Complete hydraulic simulation and analysis for a hypothetical dam break of Meja dam was performed using HEC-RAS model with river geometry derived from DEM. HECRAS public domain software to the application of combined flood routing and flood level forecasting. The details of water surface elevations, depth of flood, flood arrival time and velocity of flood wave at different locations of downstream gives an idea about extent of flooding. The outcome of the modeling showed that in the event of failure of Meja dam, some areas which include residential, agricultural and industrial areas were identified to have very high risk of being inundated due to the significant difference in the value of water surface elevation and ground elevation. Simulation of dam break result and resulting floods are essential for characterizing and reducing negative effects occurred on the downstream area. Development of emergency action plan requires exact estimation of inundation level and the arrival time of flood wave at the downstream point.