TITLE:
Analysis of the Impact of River Erosion in the Saloum Delta: The Case of the Mar Islands (Fatick, Senegal)
AUTHORS:
Omar Baldé, Mouhamadoul B. Diouf, Ibrahima Diouf, Abdou Sagne
KEYWORDS:
Saloum Delta, Coastal Erosion, Hydrosedimentology, Aquifer Salinisation, Estuarine Dynamics
JOURNAL NAME:
Journal of Geoscience and Environment Protection,
Vol.14 No.7,
July
23,
2026
ABSTRACT: This study analyzes the interactions between morphosedimentary dynamics and groundwater quality in the Mar area, located in the Saloum Delta (Senegal). It is based on the analysis of bathymetric, hydrodynamic and diachronic coastal line data, supplemented by hydrogeological and hydrochemical observations. The results show a marked asymmetry in the channel, characterised by greater depths and high current velocities on the concave bank, where shoreline retreat rates reach −0.62 m/year upstream and −0.96 m/year downstream of the Mar Islands. This dynamic reflects active erosion linked to the concentration of hydrodynamic energy and a deficit in sediment supply. Conversely, the convex bank is characterised by low-energy conditions favouring sedimentation and the smoothing of the bathymetric profile. From a hydrogeological perspective, shallow aquifers are highly susceptible to salinisation processes linked to the intrusion of estuarine waters, whilst deep Paleocene and Maastrichtian aquifers constitute the main sources of water supply, despite occasionally high mineralisation and fluoride concentrations exceeding drinking water standards. The study highlights a close relationship between coastal dynamics, hydrosedimentary processes and the gradual deterioration of groundwater quality. It thus underscores the vulnerability of the Saloum Delta’s estuarine systems to natural and human-induced pressures, and the importance of integrated management of water resources and coastal environments.