Flash floods are a recurring water security threat in Kampala Capital City and its neighbouring Greater Kampala Metropolitan Area (GKMA) municipalities. The rapid urbanization of Greater Kampala has led to an increase of impervious surfaces in ecologically sensitive areas which are relevant for flood control. Kampala’s drainage systems have outlived their design capacity and are often blocked by solid and plastic waste, as well as silt, emerging from adjacent communities. These problems are exacerbated by limited collective action across sectors (public, private, civil society and community) in operating and maintaining the drainage systems, and on awareness measures regarding storm water management. Destructive flash floods moreover pose severe socio-economic challenges to both businesses and residents of Greater Kampala. About 10% of Kampala’s jobs are at risk alone due to their location in flood risk zones.