Integrating GIS and Analytical Hierarchy Process to Determine Flood Vulnerability Level in Surabaya, Indonesia

Flood is one of the hydrometeorological disasters that occur in Surabaya, especially during the rainy season. The occurrence of floods brings a huge impact on the economy, the environment, and humans' losses. Based on the National Disaster Management Agency in Indonesia (BNPB) records, the flood inundation height in Surabaya reach about 10 -70 cm for 6 hours. Some anticipation efforts are required to minimize the impact. Therefore, this study aims to provide a flood vulnerability level assessment using the GIS and Analytical Hierarchy Process (AHP) method as a priority recommendation in increasing capacity. This research uses 4 criteria in the assessment including social, economic, physical, and environmental. Each criterion is divided into several classes with adjusted scoring values. The results of the AHP rank the social criteria as the highest weighted value of 0.42322. Furthermore, the results of the flood vulnerability assessment yield some areas that have the highest vulnerability value including Trengilismejoyo District, Wonocolo District, Dukuhpakis District, Sukolilo District, Krembangan District, Semampir District, and Benowo District.