Risk-level assessment system on Bengawan Solo River basin flood prone areas using analytic hierarchy process and natural breaks: Study case: East Java

Indonesia has the geographical conditions which are particularly vulnerable to disasters, especially floods and climate change. Throughout Indonesia, it is recorded that there are 5,590 main rivers and 600 rivers have the potential to cause flooding among others. One of it is Bengawan Solo River, which is the longest river in Java. The floods that hit the area have resulted in disruption of public health, disrupted economic activity, and damaged urban infrastructure. The phenomenon of floods and their negative impacts in the area of the Bengawan Solo river banks, indicating a condition of the area and the public about the lack of understanding of the characteristics of the hazards, behaviours that lead to degradation of natural resources, and lack of early warning that causes unpreparedness and inability in the face of danger. The purpose of this project is to be able to create an information system that can provide an assessment of the risk management in the Bengawan Solo´s flood prone areas that passed in the province of East Java, by building a web-based information system that includes information on threats, vulnerabilities, and capacities, summarized in the disaster risks analysis that integrated with Geographic Information System to provide mapping areas that have high levels of risk in accordance. Based on the factors that are already said above and calculated by Analytical Hierarchy Process, the result of this project is a map with marked regions divided into three levels of risk like High, Medium, and Low using Natural Breaks to divide it. It also, by providing the risk-level for the regions, help the system to assess how much impact and damage that will be hit the risky area and give the recommendation to government and people how to increase the preparedness so it can reduce the damage from flood.