Analysis of Suitable Areas for Shelters and Evacuation Routes: A Case Study of the Flood in Khlong Nathawi Subwatershed, Songkhla Province

Abstract

This research aimed to analyze suitable areas for shelters and evacuation routes in flood of Khlong Nathawi subwatershed, Songkhla Province by using the application of geographic information systems and network analysis. The analysis of suitable areas for evacuation from flooding areas consisted of 7criterias as:  road route, stream route, mean sea level, flood area, land use and land cover, slope and soil drainage capability. The hierarchical analysis was processed to determine the important weights of criteria. In addition, the frequency ratio method was calculated to define the score of the classification group in each factor in the area that never flooded. Then, the sum of the scores obtained from the analysis process was applied to classify the suitability of the area for evacuation. According to analyze the location of the shelters, the researcher chose the district office, temple, health promoting hospital, hospital and school. The center of each districts and villages were addressed by the sieve analysis and the nearest location. Finally, the evacuation routes were managed and displayed data via Google Earth. As the result of research, the suitable areas for evacuation were the highest, high, moderate, low and lowest range that covering 28.58 %, 15.54 %, 30.03 %, 18.29% and 4.55 % of the areas, respectively. As for the suitable location for the shelter, there were 52 places which were suitable route for evacuation in the shortest period.