Analysis of the Risk of Flooding in Bangkok and Perimeter

Abstract

Flood is a natural disaster caused by several factors. It affects people in huge ways, such as living, the environment, the economy etc. Thailand has been facing this problem for a long time, especially in Bangkok and its vicinity. Therefore, those areas need to be analysed for the risk of flooding. This research uses AHP (The analytical hierarchy process) and geographic information engineering techniques of Geographic Information Systems to analyse the risk of flood areas and create a map for further flood management and mitigation by using factors of DEM (Digital Elevation Model), slope, rainfall, repeated flood and land use. After that, weight factors which affect flooding are then reclassified. The data will be displayed as a research area flood risk map. Classify the risk as highest, high, moderate, low and normal. The results revealed that the most significant result was a moderate risk level, approximately 1,842.72 square kilometres, by 45.71% of flood areas. The low-risk level was 1,474.59 square kilometres, by 36.58% of flood areas. The high-risk level was 458.89 square kilometres, by 11.38% of flood areas. The normal risk level was 132.23 square kilometres, by 3.28% of flood areas. Moreover, the highest risk level was 122.47 square kilometres, by 3.04% of flood. the overall accuracy of the risk analysis was 77.6%and coefficient’s kappa was 0.68. Therefore, the consistency was in the good standard.