Assessment of the Vulnerability of Residential Areas to Floods in Mabatini Ward in Mwanza City Council, Tanzania

Abstract

Flooding is a growing problem in Mabatini Ward, Mwanza City, where many people live in crowded settlements with poor drainage and weak infrastructure. This study assessed how vulnerable these residential areas are to floods by combining maps, satellite images, and community input. Results show that vegetation has reduced by more than 40% since 2005, while built‑up areas have more than doubled, creating more hard surfaces that increase runoff. Analysis of the Mirongo River buffer zone found over 6,400 buildings and about 25,600 residents at risk. Flood maps revealed that water can remain stagnant for several days in low‑lying areas, especially where houses are built too close to the river. The findings highlight clear hotspots of risk and show that unplanned urban growth is worsening flood impacts. To reduce vulnerability, the study recommends better drainage systems, stricter land‑use planning, replanting vegetation, early warning systems, and stronger community awareness. These measures can help improve resilience and protect lives and property in Mabatini Ward.