The effects of climate change on tropical ecosystems cannot be interpreted based on physical variables alone. Severe water shortages and deterioration of ecosystems are most acute in places where historical inequalities occur, such as unequal access to land and other goods and rights necessary for the livelihood of marginalized populations. This paper explores environmental transformations and their repercussions on water resources based on spatial analysis and fieldwork carried out in the Colombian Caribbean. We have engaged with peasant and Afro-descendant populations who have been excluded from water use and now face problems in sustaining their way of life.