IWRA World Water Congress 2008 Montpellier France
1. Water availability, use and management
Hama Maïga (2IE)
Bruno Barbier (CIRAD)
water management, irrigation,
hydroelectricity, clean water, sanitation, water policies
Abstract West Africa displays the worst indicators in terms of water services. Access to clean water and
sanitation, irrigation and power from hydroelectric dams is less developed than anywhere else in the world despite
the progress made during the last decades. Children mortality, closely linked to water quality, is still among the
highest. As irrigated area is insignificant, agriculture is almost completely climate dependant, and the climate is also
the most variable on earth. The hydroelectric potential is still very important, since the potential of the mountains of
Fouta Djalon is almost untapped, while energy costs are the highest in the world. Sanitation networks are rare or
deficient while wetlands, rich in biodiversity are disappearing or increasingly contaminated.
Water use is
becoming an increasingly contentious issue in West Africa and might become a major constraint to economic
development. The combination of rapid population growth, even faster urbanisation and robust economic growth
fuels the demand for better public services. As food security remains a priority, farmers and herders are asking for
more irrigation scheme, wells and boreholes. However competition for water is rife. As oil and natural gas prices are
rising, hydroelectric projects reappear on policy makers’ and donors desks. Where should the money go: drinking
water, food security or electric power?
Proper use of the water resources will require new discussion
between states sharing the major hydrologic basins and the transnational aquifers. The river basin authorities have
become the central place of decision making as well as the ECOWAS sponsored West African Power Pool
particularly concerned by hydroelectric investments.
Hydroelectricity is perceived as a sound alternative to
hydrocarbures, but it will be constrained by climate variability. The ongoing West African power interconnection is
bound to reduce the risk of power shortage but the characteristics of the west African monsoon make rainfall levels
quite covariant. Water flow in the Senegal, Niger and Volta rivers are similar. A major drought means a deficit
everywhere in West Africa. The choice of investments will require sound and sophisticated technical and economic
analysis which will incorporate the calculation of risk of extreme events.
An effort of imagination and
research is also required to improve irrigation, because current methods are expensive, not really cost effective and
fragile. Irrigated rice production displays poor competitiveness in regards to Asian imports and local high value crops
such as vegetable and fruit production which are in full expansion. High value crops display serious problems of
contamination by pesticides. Public concern for water quality will increase as consumers are becoming more
demanding. Clean water for human consumption will require compromise between dams, pumping the aquifers and
maybe desalted water for large coastal cities. A key question is whether cities can afford complex urban sanitation
network based on water. This water will have to come from surface water, better if it is recycled.
West Africa has a fair potential in water resources, be it surface water or aquifers, to satisfy the growing demand. It
requires new plans to improve its infrastructure. The plans will need to be managed at the ECOWAS level because
the water resources cross boundaries. But African technical and managerial capacities need to be improved to
permit the investment plan to achieve both rapidity and sustainability.