Morphological and Hydrodynamic Changes in the Lower Estuary of the Senegal River: Effects on the Environment of the Breach of the ‘Langue De Barbarie’ Sand Spit in 2003 - The Land/Ocean Interactions in the Coastal Zone of West and Central Africa - page 22

Morphological and Hydrodynamic Changes
in the Lower Estuary of the Senegal River:
Effects on the Environment of the Breach
of the 'Langue De Barbarie' Sand Spit in 2003

Awa Niang and Alioune Kane

Abstract
The Senegal River estuary and its coastal interface, the 'Langue de Barbarie', a long sandy
spit shaped by the littoral dynamics, are located in Sahelian zone. Their instability results in
considerable risk to their hydrological, climatic and ecological balances. The ecosystems
there have suffered severely from the effects of drought and reduced freshwater inflows.
Dams have partly dealt with the problem of water availability, especially in the upper basin.
But the effects of their management on the environment have often been criticized. The
breaching of the Langue de Barbarie sand spit on 4 October 2003 was justified by the
imminent flooding of the city of St. Louis. It allowed the rapid escape of the flood waters of
the Senegal River and thus saved St. Louis. The initial channel of 4 m width is now 2 km
wide, with significant changes to the environment. This rapid evolution of the breach was
accompanied by major impacts on the environment. Today, the lower estuary of the Senegal
River is at a critical stage of its history with the accumulation of vulnerability factors such as
the development of a marine dynamic, the over-salinization of water and lands and the rapid
morphological change of the Langue de Barbarie sand spit caused by severe coastal erosion.
In socioeconomic terms, despite the attempts of the communities to adapt through the
development of activities such as salt extraction or the move of market-gardening activities
towards

less disadvantaged areas, the situation remains alarming, in view of the

impoverishment of the local communities.

Keywords

Senegal river Estuary Sand spit Langue de Barbarie Hydrodynamics Morphology of

the estuary Salinization Environmental change

Introduction

The lower estuary of the Senegal River, like the rest of the
basin, has, since the beginning of the great drought of 1970,
seen a series of developments and actions in line with sig-
nificant changes in its environment. This is one of the

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