The paper proposes to shed light on the articulation of global processes typical of urban trajectories in southern cities and crises at the local scale, based on a comparative analysis in two cities frequently affected by floods, Dakar (Senegal) and San José (Costa Rica). In doing so, the paper aims to clarify the notions of 'crisis' and 'disaster' in urban contexts in the Anthropocene by linking them to that of 'saturation'. We highlight three results. First, using flooding as an example, saturation sheds light on the processes that shape cities and their disasters. Second, saturation highlights the specific ways in which water interacts with urban environments. Finally, the findings touch on the capacity of actors to cope with these crises.