*Water Resources Management and Hydraulic Infrastructures in the Senegal River Basin… DOI: http://dx.doi.org/10.5772/intechopen.105633*

The Senegal River, which is the second largest river in West Africa, owes its formation to the joining of the Bafing and the Bakoye rivers at Bafoulabé, Mali. Its 300,000 km2 watershed is divided into three subsets [9]: the upper basin, the valley and the delta as seen in (**Figure 5**). The Senegal River runs through four distinguishable climatic zones:


At 1500 mm/year in the Guinean part the rainfall gradient remains poweful compared to 200–250 mm/year in the northern part leading to an annual average of 550 mm/year, a pluviometric contrast that is a a main basin characteristic which is attenuated to a ceratin extent as billions of m3 of water are transferred annually by the river from the the upper basin wet regions to the the valley and the delta arid Sahelian regions [10, 11], which explains the great wealth of biophysical environments in the basin and their great diversity.

The impacts of the dam are often examined without taking into account the forms of knowledge of the inhabitants who experience them. The weakness of the

### **Figure 5.**

*Situation of the Senegal River watershed and the dams built and planned.*

approach to social questions in a context of research into sustainable development is denounced by sociologists, anthropologists, agrogeographers, historians, economists and geographers. On the Manantali dam, the first studies date back to the 1970s. They focused on calculations and simulations before and after the construction of the dam and the hydroelectric power station. The creation of the reservoir, the fish population, the quality of the water, the flows, and the regime of the river were thus questioned. Legally, the status of the Manantali dam is qualified as co-ownership. The specific role of the Organization for the Development of the Senegal River (OMVS) in the operation of the Manantali dam is underlined in certain studies, and the success of the bet on regional integration around the Senegal River is particularly mentioned.

Water withdrawals vary by country. In Senegal, in 2000, withdrawals from water resources amounted to 1591 million m3 including 1435 million for agriculture (93%), 98 million for communities (4%) and 58 million for industry (3%). In Mauritania, in 2000, water withdrawals were estimated at 1698 million m3 including 1.5 billion for agriculture (88%), 150 million for domestic use (9%) and 48 million for industry (3%). In Mali, the current withdrawals of the irrigation sector are of the order of 5.0 km3 in 2006, or 96.4 percent of the total withdrawal [12], and come almost entirely from water resources, surface and almost entirely over a period of 6 months. In the Senegal River Basin water resource availability and distribution are influenced by factors such as: population dynamics, extremely variable climatic conditions ecosystem maintentenance water-affecting environmental issues, and political/sociocultural issues e.g., food security, and the problem of economic development [13].

Based on the OMVS agreements framework it is seen that via the Manantali dam management a minimum low water flow at the Mali/Senegal border is guaranteed and the Mali, Senegal and Mauritania agreed sharing of stored water is ensured. Thus, a sectoral plan declining master frameset for the development of the Senegal River (SDAGE) is applied in order to attempt the promotion of the watershed's sustainable and concerted development [9].

The water-scarce Sahelian countries, Senegal, Mali and Mauritania, lying on the border of the Senegal River basin have invested in water storage for a long time so as to increase water availability to satisfy their socio-economic/environmental needs. This leads to the question raised here, whether current storage capacity is sufficient to cover the future development needs of these three countries. To be more precise, the Senegal River basin water storage capacity must be assessed taking into consideration whether the OMVS supported potential of these countries is realistically capable to increase this capacity. This paper assesses the the Sahelian countries bordering the Senegal River Basin current water storage capacity from the poin of view of integrated water resources management.
