This article examines the environmental and socioeconomic consequences of hydraulic infrastructural changes along the Senegal River valley and estuary. It examines the impacts of these infrastructural changes, using on-site measurements (topometry, water salinity and piezometry), analysis of hydrological data, field observations and surveys with dam managers, state regional directions and local stakeholders. It stresses the urgency of elaborating models of hydraulic management to limit the negative consequences of the hydraulic constructions.