The Gambia
Barrage on River Gambia might be hazardous

afrol News, 30 October - Last Friday, the Board of Directors of the African Development Fund approved a grant of nearly US$ 3 million to finance the study on the means of production and transmission of electric power from River Gambia. As the region is in desperate need of energy, a barrage and an electric power plant on River Gambia might be a natural project. The thought of barraging River Gambia is not new, however, and studies in the 1980s showed that it would do great harm on the environment.

The recipient of the grant from the African Development Fund were the member states of the Organisation for the Development of the River Gambia (OMVG), a regional organisation whose members are the Gambia, Guinea, Guinea Bissau and Senegal.

According to the African Development Fund, the objective of the study will be "to strengthen the regional integration and cooperation of OMVG member states in the energy sector, and especially in the electricity sub-sector. It particularly seeks to prove the technical, economic, financial, environmental and social feasibility of the Sambangalou hydroelectric dam project and the interconnection network project linking this station to the load centres of the four countries. The study will also establish different financing scenarios as well as the institutional framework to be envisaged for the projects implementation and operation. The study will involve feasibility studies as well as social and environmental impact studies."

The regional energy situation
The Gambia has no other natural sources of energy than fuelwood. Surveys of the energy consumption in The Gambia show that fuelwood is the principal source of energy (mainly for cooking) in 95% of the urban households, the number estimated to be even closer to 100% in rural households. Alternatives are gas (in cylinders), kerosene and, for a few households, electric energy. All electric energy is produces by petroleum generators. Electric energy is not available for most households due to the lack of infrastructure and the cost of production. Energy equivalent costs for cooking show that electricity prices range from 3 to 5 times higher than fuelwood, depending on oil prices. The collection of fuelwood is also seen as one of the most serious threats to Gambian forests.

Fuelwood sale on the Gambian highway

Further, electricity boards can not guarantee stable deliveries and power failures are frequent. This is of course a major obstacle for business in The Gambia. Most serious businesses, therefore, have their own generators, non-regarding costs being high. Although The Gambia represents the extreme in the region, having to import all its energy, apart from fuelwood, the situation is comparable in the neighbouring OMVG countries. None of them are oil producers.

On this background, there is substantial need for an indigenous production of energy in the region. So far, there has not been found offshore oil off the coast of Senegambia, and the abundant rivers have been the source of attention. Production of solar and wind energy have not been considered seriously.

Previous studies said 'no' 
This is not the first time there has been proposed a regulation of River Gambia. As late as the 1980s, there existed plans for a Bridge Barrage Project in Central Gambia, regulating the volume of discharge of the river and improving The Gambian infrastructure. The Bridge Barrage Project was also to provide a stable water level upriver, which was seen as a condition for the gigantic rice irrigation projects planned. The project was studied by The Gambian government and independent scientists. One of these was the recognized Professor J.M. Trolldalen, which did his thesis about the Bridge Barrage Project in The Gambia in 1983.

Conclusions were clear. It would have been an environmental and economic disaster. Firstly, the project would not pay off because rice irrigation projects in The Gambia do not pay off (imports are too cheap and there is not enough labour in The Gambia to implement such gigantic projects), and there is no traffic base in The Gambia to defend such investments in infrastructure. The river crossing can easily and efficiently be handled by ferries.

More severe, even, were the expected environmental side-effects. River Gambia is a mangrove river with salt water intrusion up to the centre of The Gambia. Any barrage would rip the water off the sediments it is transporting, which are captured by the mangroves and which stabilize the erosion of sea and river water. It was also foreseen that the parts of the river below the barrage would be more exposed to salt water intrusion, and that intrusion would reach further into the country, thus making conditions for agriculture impossible. The possibly affected areas are were small scale farmers today produce their rice. 

A more stable volume of discharge would also prevent flooding, which might sound practical, but which isn't. Flooding of the riverbanks deposits river sediments, which are rich on fertilizers. It is the natural way of fertilizing the earth (when the water carries sediments), and the reason why riverbanks always are more fertile grounds than other areas. The history of River Nile illustrates this clearly. The Nile has, for thousands of years brought two things to the cultures of Egypt - water and nutrients. As the prestigious Assuan Barrage was built, hopes were great for the greatly increased production of electricity and for gaining control of the river. The lack off annual floods, however, has deprived Egyptian farmers of one big resource, the nutrient sediments the river was carrying. It has been estimated that it would be needed far more energy than the Assuan Barrage gives to produce the fertilizers farmers now fail to obtain.

River Gambia between Basse and Fatoto (Gambian interior)

Other side effects are the spread of diseases like malaria (due to mosquitoes breeding in still waters) and schistosomiasis (bilharzia). The lake created by the barrage would have been the cause of this seemingly inevitable spread of both diseases. Especially schistosomiasis is known to thrive around human-made water bodies, which has been clearly documented in studies of the African Lakes Kainji (Nigeria), Kariba (Zambia/Zimbabwe), Volta (Ghana) and Nasser (Egypt).

Finally, The Gambia being the smallest country on the African continent, located on the riverbank of River Gambia, any loss of land through flooding or environmental degradation would be too risky. One must also remember that The Gambia has one of the highest population growth rates in Africa (3,4% annually).

Lessons
The new project planned would be further upriver, thus causing less damage. Any barrage, however, would remove sediments from the river water - it's a natural law that standing water does not transport elements. This will effect the stability of the river in its lower parts, opening it for erosion and intrusion of salt water. Further, it will restrain deposits of nutrient sediments, both because the water will carry less sediments and because regulating discharges prevents flooding. Land losses and infertile riverbanks might be the output. 

The region certainly needs energy, but the price might be too high to pay. The Gambian population heavily depends on its domestic food production. There is little possibility that electricity would be an alternative for the rural population, considering the price and the need for constructing a totally new infrastructure. Alternatives, which have worked in other regions, are local sun power plants, needing less investments in infrastructure and being more adaptable to local needs without posing environmental risks.

In basic terms: this generally is not an ecosystem which sustains projects of this type, and The Gambia cannot afford to lose anything. Let's hope, thus, that the Organisation for the Development of the River Gambia will produce a proper environmental risks assessment and that the decision to construct not already has been taken.

 By Rainer Chr. Hennig

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