This study is an evaluation of the water potential of the Ferlo fossil
valley in the Louga area in Senegal. It consisted in determining the volume of
water that could be mobilized at the level of a confluence point of the waters
according to the flow lines, where a dam would be placed to create a reservoir.
This volume of mobilizable water was compared to the average water consumption
of the area in order to evaluate its adequacy or not. To do this, a
delineation, physical characterization and mapping of the Ferlo watershed was
done using Google Earth, Global Mapper and Arc GIS softwares. A catchment area
of 28,754 sq·km was obtained with a perimeter of 976 km, an average slope of
0.52% and a hydraulic length of 336 km. Then the decennial runoff of the
watershed was calculated using the CIEH method, this flow is estimated at 1120
cm/s. On the basis of this flow, the annual volume of water that can be
mobilized was estimated at 11,089,758 cm per year with a solid deposits of 93
cm per year. The conclusions reached are that there is a lack of mobilizable
water resources in the area and that the entire fossil valley needs to be
rewatered to provide a sustainable alternative water source.
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