Flood Vulnerability Analysis Using Ahp Method in Puwajaya Village, East Kalimantan, Indonesia

Abstract

The analysis of flood-vulnerability areas in this study uses the help of a Geographic Information System (GIS) where GIS capabilities can be harmonized with remote sensing. This analysis uses five criteria, namely (1) Slope (2) Land Use (3) Distance to River (4) Rainfall (5) Rock Unit. By using three alternative approaches, Scenario 1 was analyzed with five basic criteria, Scenario 2 was analyzed with 4 basic criteria except rock units, and Scenario 3 was with 4 basic criteria except rainfall. The results of the analysis of all parameters were then compared and weighted using the Analytic Hierarchy Process (AHP) Pairwaise Comparison matrix. The weight value for scenario 1 is 0.278, scenario 2 is 0.436 and scenario 3 is 0.284. The highest scenario is scenario 2 with the weight criteria being 0.53 rainfall, 0.20 land use, 0.14 slope, and 0.13 distance to the river. From the slope analysis, the research area is in plains (at a slope level of 0-13% to 21-55%). The dominant land use in the research area are forest and ex-mining areas. The closest distance to the river is <100 meters. Rainfall analysis using the Ishoyet method resulted in the distribution of rainfall <13.6 mm which was included in the low category. All analysis results are combined using the Overlay Intersection method in ArcGIS 10.4 to produce a map of flood-vulnerability areas based on the 4 criteria used. It was found that 5% of the research sites is very vulnerable to flood, 25% of the research sites is vulnerable to flood and 10% of the research sites is endangered to flood.

Keywords: Flood, Geographic Information System (GIS), Analytical Hierarchy Process (AHP), ArcGIS