Flood risk analysis of streams flowing into van lake

In this thesis study, a flood risk analysis was conducted in the Lake Van Basin, which is the largest closed basin in Turkey. Today, factors such as climate change, population growth, and unplanned urbanization are increasing the frequency and impact of natural disasters. In this context, it is of great importance to predict potential floods in the Lake Van Basin in advance and to map these risks. Floods, which cause the highest loss of life and property after earthquakes worldwide, not only result in such losses but also lead to environmental and economic problems. In this study, flood risk maps were produced by using Geographic Information Systems (GIS) technologies in conjunction with the Analytical Hierarchy Process (AHP), one of the multi-criteria decision-making methods. Within the scope of spatial analysis, seven parameters—slope, aspect, geology, major soil groups, land use, and precipitation data—were evaluated. Each parameter was weighted using the AHP method, and spatial data layers were overlaid in a GIS environment to create a flood risk map for the Lake Van Basin. According to the analysis results, areas near riverbeds, low-elevation plains, and densely populated regions around Lake Van are at high risk of flooding. Moreover, the fact that a significant portion of agricultural lands is located within these high-risk zones indicates a high potential for economic loss. The accuracy of the risk maps was supported by spatial analysis of historical flood events in the region. This thesis aims to provide a decision support tool for local governments, planners, and disaster management experts within the framework of flood risk management. Additionally, the study serves as a methodological example for conducting flood analyses in similar basins.