Flood Hazard Mapping at Long Xuyen Quadrangle in 2015 Using Geographic Information System and Remote Sensing Technologies

Abstract

In recent year, the flooding has occurred with high frequency at LXQ (Long Xuyen Quadrangle) areas of Mekong Delta, Vietnam. It was considered as a major natural disaster which has effects on the physic and spirit in people’s life in this area. This research aims to generate a flood hazard map and assess the flood situation at LXQ in 2015. The MNDWI (Modification of Normalized Difference Water Index) extracting from Sentinel-2 image was used to map the flood extent at LXQ during rainy season in 2015. The statistics method estimated correlation coefficient between flooding spatial distribution and hydrological stations on SPSS (Statistical Product and Services Solutions) software. The results showed that the severe flood occurred from August to December in 2015. There were about 47.6% and 28.2% of the total areas that were inundated in October and August, respectively. The correlation between inundated areas and water level at Ha Tien and Chau Doc hydrological stations was 0.73 and 0.65 (p < 0.01), respectively. The derived information was very essential and valuable for local managers in making decision on responding and mitigating to the flood disaster.