FLOOD INUNDATION ANALYSIS IN LOW-LYING RIVER BASIN USING DIFFERENT DIGITTAL ELEVATION MODEL

Abstract

 The purpose of this study is to clarify the differences in flood inundation analysis results when different elevation data are used in flood inundation analysis in low-lying areas. The elevation data used in this study showed an average difference of 2 m to 4 m in low-lying coastal areas compared to the elevation data obtained by airborne laser scanning. The results of the flood inundation analysis at a spatial resolution of about 250 m using these data indicate that the maximum inundation depth is 0.86 m in the case of the smallest average difference between the calculated and measured values, and 0.66 m using the airborne laser scanning elevation data. And we conclude that this difference must be tolerated in the present situation, and that the accuracy of the elevation data is not necessarily proportional to the accuracy of the analysis.