Mapping Flood Risks across the Thiès City Catchment Area Using the Flood Potential Index (Senegal)

Abstract

Flood risk management in Thiès, a city in Senegal, has become a major challenge due to rapid urbanization and the impacts of climate change. The main objective of this study is to assess flood potential in urban areas using the flood potential index (FPI), a multi-criteria method integrated into a geographic information system (GIS). This approach makes it possible to map vulnerable areas and identify contributing factors such as topography, precipitation, urbanization, and drainage infrastructure. The results show that certain areas of Thiès, particularly low-lying areas close to drainage networks, are particularly exposed to flood risks. Factors such as poor drainage infrastructure capacity, soil degradation and the lack of strict land use regulations amplify the city’s vulnerability. In the city of Thiès, flood risk is classified into five levels. 27.22% of the area is at moderate to high risk, 19.86% at high risk and 9.66% at very high risk, requiring urgent action. This study also highlights the importance of integrating IPI into urban planning and risk management policies. The results suggest that mitigation strategies, such as improving drainage infrastructure, rehabilitating soils and integrating green spaces, are necessary to reduce the impact of flooding in Thiès. Ultimately, proactive flood risk management will require greater collaboration between local authorities, urban planners and the scientific community.