Large Dams and Uncertainties: The Case of the Senegal River (West Africa)

Abstract

This paper examines the environmental and socio-economic consequences of hydraulic infrastructural changes along the Senegal River valley and estuary. During the 1980s, two dams were built along the valley floor to facilitate hydro-electrical production and regular water supply for crop irrigation. In 2003, a breach was dug across Barbary Spit to alleviate flooding in the nearby Saint-Louis city. Although these structures helped regulate the river flow, they also resulted in a series of unforeseen impacts. The study examines these, after on-site measurements (topometry, water salinity, 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. These models should consider the variety of water uses in the middle valley and delta, and also the water safety and quality (salinity) downriver from Diama Dam.

The cross-cutting contribution of the end of neglected tropical diseases to the sustainable development goals

“…For example, it has been shown that the construction of large dams has led to increases in human schistosomiasis in China, Cote d’Ivoire, Egypt, Ethiopia, Senegal [104], and Sudan, amongst others [105–107]. Dam spillways are known to serve as breeding sites for blackflies [108], and the construction of dams can lead to complex changes in habitat, which in addition to movement of non-immune populations and snails into the area can lead to transmission hotspots [109]. Evidence for beneficial inter-sectoral collaboration includes a study examining the impact of dam construction in Senegal and Mali, which showed the beneficial impact of control of water-related NTDs, including control of snails and mosquitoes [109].…”

“…Dam spillways are known to serve as breeding sites for blackflies [108], and the construction of dams can lead to complex changes in habitat, which in addition to movement of non-immune populations and snails into the area can lead to transmission hotspots [109]. Evidence for beneficial inter-sectoral collaboration includes a study examining the impact of dam construction in Senegal and Mali, which showed the beneficial impact of control of water-related NTDs, including control of snails and mosquitoes [109]. When initiating sustainable energy infrastructure, the existence of good control interventions for NTDs can ensure that the negative impact on health caused by NTDs will be mitigated.…”

Evolution of the Sahelian Coastal Water Table Under the Influence of Anti-salt Dam, in Salt Leaching Process

“…This intrusion of seawater has increased salinization of land [9,10], surface water [11] and ground water [12]. Given the scale of this soil's degradation, several actions have been undertaken, including anti-salt dams [13,14]. So, the objective of this work was to understand the impact of these dams on the fluctuation of ground water during wet season.…”

Sustainability Assessment of Large Irrigation Dams in Senegal: A Cost-Benefit Analysis for the Senegal River Valley

“…The channel rapidly widened reaching 2.4 kilometers in 2006. As a result, the daily tidal range had a threefold increase (Mietton et al, 2007) and the estuary water salinity also increased, reducing the delta gardening, and threatening the remaining delta forest and pastures (Dumas et al, 2010).…”

“…The presence of dams and the associated hydraulic structures have contributed to the ecological and socio-economic changes in the Senegal River estuary as well (Dumas et al, 2010). In 2003, to protect Saint Louis town against periodic floods, a 4-m wide channel was dug across a narrow spit of sand that blocked the flow of the river to the ocean.…”