The largest proportion of the world’s urban development and new expansion is not a result of conscientious planning, which increases urban vulnerabilities to disaster risks. Accordingly, SDGs, including Goals 1, 11, and 13, concentrate on minimising vulnerability to disasters like floods and boosting resilience (Anwana & Owojori, 2023). Therefore, there is a need to study the linkages between different patterns of urbanisation and vulnerabilities of cities to climate change-induced disaster risks. This study traces the significance of different urbanisation parameters in contributing to flood disasters in urban sub-catchments in the seven Tanzanian secondary cities. The urbanisation indicators considered are those based on environmental conditions or physical locational qualities and those based on changes in anthropogenic factors. The findings demonstrate a strong correlation of flood occurrences with the fragility of the locations, as indicated by the steep slope and proximity of the built-up areas to a permanent water body. Other urbanisation factors for urban floods are continuous densification through residential land subdivision and a lack of proper stormwater management infrastructure. The findings indicate that regardless of whether the area is planned or unplanned, flood risk is primarily driven by settlement in fragile locations (steep slopes, proximity to water), increased impervious surfaces from densification, and inadequate infrastructure, rather than by changes in precipitation.
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