GIS-Based Urban Flood Risk and Hazard Mapping: The Case of Mekelle City, Tigray, Ethiopia.

This thesis presents a GIS-based assessment of urban flood hazard and risk for Mekelle City, Tigray, Ethiopia. The study integrates spatial datasets including Digital Elevation Model (DEM), land use/land cover, drainage network, soil type, and rainfall data to identify flood-prone areas and evaluate flood risk levels. Geographic Information System (GIS) techniques and multi-criteria decision analysis (MCDA) were applied to generate flood hazard and flood risk maps. Key contributing factors such as slope, elevation, proximity to rivers, drainage density, and urban land use were weighted and overlaid to determine hazard zones. Flood risk was further assessed by combining hazard information with exposure and vulnerability indicators, including population density and built-up areas. The results highlight areas of Mekelle City that are highly vulnerable to flooding, providing valuable information for urban planning, disaster risk reduction, and flood management strategies. This research demonstrates the effectiveness of GIS as a decision-support tool for sustainable urban flood risk management in rapidly growing cities.