Author(s): Jonathan Salar Cabrera; Han Soo Lee
Linked Author(s): Han Soo Lee
Keywords: Multi-criteria analysis; Flood risk; Hazard map; GIS; Davao Oriental
Abstract: Flooding is one of the major and destructive natural disasters in Davao Oriental, mainly resulted from a high incidence of Typhoon and heavy rainfall in the Philippines. Flood risk occurrence is a combination of human and natural factors, which needs a better understanding of its characteristic and spatial distribution. The main objective of this study is to identify the flood-prone and risk areas by mapping them based on several factors (rainfall, slope, elevation, drainage density, soil type, distance to the main channel and population density). For this purpose, a GIS-based flood risk spatial assessment conducted under the concepts within analytic hierarchy process (AHP) framework in the province of Davao Oriental, Philippines. This paper was based on the integration of multi-criteria data including rainfall, slope, elevation, drainage density, soil type, distance to the main channel and population density. The result of the AHP flood risk map shows that Davao Oriental is under low and moderate flood risks, which cover 95.38% of the total study area. The high and very high flood risk areas which cover approximately 3% of the province, primarily in the coastal areas. The multi-criteria analysis using AHP method allowed the integration of the several indicators under two criteria: hazard and vulnerability for flood risk mapping. Results show that the province of Davao Oriental slightly exposed to the risk of flooding. Twenty-three out of one hundred eighty-three (23/183) barangays (towns) are at a high to very high risk of flooding that calls immediate attention for decision-makers to develop strategies for future occurrence of flood within the province of Davao Oriental. An effective strategy should be established in barangay level since each barangay area has its own physical and social characteristics.
Year: 2018