Flood Risk Mapping Using HEC-RAS and GIS Technique: Case of the Xe Bangfai Floodplain, Khammoune Province, Lao PDR

Main Article Content

Sabay Thoummalangsy
Venus Tuankrua
Somnimirt Pukngam

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.

Downloads

Download data is not yet available.

Article Details

Section
Review Articles

References

[1] Department of Water Resource. 2014. Flood Management in Lower Xe Bangfai to 2025 Years Plan and Implementation Plan 5 Years 2015 – 2020. Department of Water Resource., Vientiane.

[2] Khalfallah, B. C. and Saidi, S. 2018. Spatiotemporal floodplain mapping and prediction using HEC-RAS - GIS tools: Case of the Mejerda river, Tunisia. Journal of African Earth Sciences. 142: 44-51.

[3] Lin, B., Wicks, J.M., Falconer, R.A. and Adams, K. 2016. Integrating 1D and 2D hydrodynamic models for flood simulation. Proceedings of the Institution of Civil Engineers: Water Management. 159(1): 19-25.

[4] Logah, F.Y., Amisigo, A.B., Obuobie, E. and Yeboah, K.K. 2017. Floodplain hydrodynamic modelling of the Lower Volta River in Ghana. Journal of Hydrology: Regional Studies. 14: 1-9

[5] Ongkeo, O. 2012. Flood Risk Analysis and Risk Management in Lower Xedone. National University of Laos., Lao PDR.

[6] Sioudom, K. 2013. Basin Profile for the Nam Theun/Nam Kading, Nam Hinboun and Xe Bang Fai, Lao PDR. Mekong Challenge Program for Water and Food Project 3., Hanoi, Vietnam.

[7] Ackerman, C. T. 2009. HEC-GeoRAS User’s Manual. Hydrologic Engineering Center, US Army Corps of Engineering., USA.

[8] Brunner, G. W. 2016. HEC-RAS River Analysis System User's Manual. Version 5.0. Hydrologic Engineering Center, US Army Corps of Engineering., USA.

[9] Moriasi, D. N., Arnold, J. G., Van Liew, M. W., Bingner, R. L., Harmel, R. D. and Veith, T. L. 2007. Model evaluation guidelines for systematic quantification of accuracy in watershed simulations. Transactions of the ASABE. 50(3): 885-900.