Flood Risk Mapping Using HEC-RAS and GIS Technique: Case of the Xe Bangfai Floodplain, Khammoune Province, Lao PDR
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Abstract
This study aims to analyze flood frequency in Xe Bangfai floodplain area and to generate a flood risk map in Xe Bangfai floodplain using HEC-RAS model. In an additional flood frequency of difference magnitude (2, 6 and 35 years return period) were calculated using Gumbel’s distribution. Also, HEC-RAS model used to simulate flood depth for different return period in Xe Bangfai floodplain. The result of the research was shown that peak flow in each flood frequency of 2, 6 and 35 years return period as 3,746.57, 4,505.99 and 5,877.60 m3/s respectively. These peak flow in each flood frequencies were selected for simulation of water surface profiles at lower part of XBF. The result from model simulation were used for flood hazard analysis and generated flood risk maps using GIS tool. The flooded areas by 2, 6 and 35 year return flood shown as 49,534.0, 53,800.0 and 56,047.0 hectares respectively. It could be said that when high peak flow, flooded area will be expanded larger than low peak flow.
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References
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