Modelling Disaster Response Route for Flood: A Geospatial Road Network Analysis Traversing the Vulnerable Zones of Candaba, Pampanga Through ArcGIS

Abstract

The municipality of Candaba in the Philippines, located near the Pampanga River, is widely recognized as the flood catch basin of the Northern and Central portions of Luzon. Barangays in the municipality continually face the perpetual challenge of flooding during heavy rains. From this, roads are becoming frequently impassable during the occurrence of typhoons. Due to the impacts of the flood on disaster response, this study aims to develop Disaster Response Route (DRR) choices for disaster response units through road network analysis using Arc Geographic Information System (ArcGIS). The study was carried out in the municipality's East River Side and Tagalog Region, with twenty-one (21) barangays under study. Furthermore, flood hazard maps with 5-year, 25-year, and 100-year flood periods from the University of the Philippines Disaster Risk and Exposure Assessment for Mitigation (UP-DREAM) were utilized to plot the DRR. These DRRs were tested based on their Levels of Service (LOS) and total time delays. Results showed that during the 5-year flood period, sixteen (16) routes were identified and ranked accordingly. From this, three (3) Disaster Response Routes were developed. While thirteen (13) passable routes were identified for the 25-year flood period, and three (3) Disaster Response Routes were established. However, for the 100-year flood period, all road links within the area of consideration were already submerged with floodwaters, resulting in no passable routes during this flood period. Following the simulation and ranking of routes, disaster response units may decide which route to take for the 5-year and 25-year flood periods. Accordingly, the said municipality is recommended to activate the Disaster Response Routes as necessary during an emergency or after the provincial or local state emergency declaration.