MANAGEMENT GUIDELINES FOR EVACUATION ROUTES IN AREAS PRONE TO FLOODING AND LANDSLIDES: A CASE STUDY OF THE MAE PHRONG RIVER BASIN AREA IN THAILAND

Abstract

Flooding and landslides have been a significant hazard in Thailand, especially in steep areas. This study aimed to find suitable evacuation routes for future disaster prevention planning and management by the local authority appropriate to the needs of affected people living in steep areas of Uttaradit province. Evacuation routes were analyzed using the trip assignment model with the optimization technique according to the shortest path and 20 vehicles (pickup trucks) used for organizational planning. The results showed evacuation with the group would take more time than for ungrouped people by almost half an hour, but the number of vehicles could be reduced by one. In addition, for both ungrouped and grouped types, increasing the number and speed of the vehicles decreased the evacuation time by about 20 minutes if the local authorities increased the number of existing vehicles from 20 to 30 and allowed a vehicle speed of 30 kilometers per hour. The information for evacuation management and period obtained in each simulation from this research would be beneficial for determining evacuation notification periods. The results could be used as guidelines for other local authority plans in steep or similar risk areas where efficient evacuation is necessary due to flooding and landslides. Important requirements can be added to facilitate evacuation, such as the road capacity during the evacuation, an alternative route during flooding even and a plan for clearing roads affected by landslides.