Desalination: a viable supplemental source of water for the arid states of North Africa

Abstract

The states of North Africa without an exception are, or will soon be, facing serious water supply shortages due to an imbalance between limited water resources and rapidly increasing water demands. The region's population has increased from just over 40 M in 1950 to over 150 M in 2000 with an even larger increase in water demand as a result of this growth and the improvement in the standard of living which has already strained the water resources. Water deficits of about 2 and 3.5 billion m3 per year (BCMY) have been estimated for the years 1990 and 2000 respectively, with a deficit exceeding 15 BCMY projected for the year 2025. If not addressed properly and immediately, these deficits will have serious impacts on the sustainability of the region's development and environment. These deficits have been exacerbated by declines in quality of both surface and ground water resources because of anthropogenic activities, thus limiting further the amount of water available. They can however, be overcome through integrated water resources management with special focus on desalination of seawater, a non-conventional, unlimited, renewable resource that is readily accessible to these countries. Desalination plants of various sizes and technologies have been in use in the region since the early 60's with an estimated total installed capacity of about 1 Mm3/d in 1990. The largest capacities are in the countries that have the most severe shortages and/or most abundant energy resources (Libya and Algeria). Cost factors have limited the uses to municipal and industrial applications. The objective of this paper is to assess the desalination potential for North Africa. To achieve this objective, an overview of the water supply and demand situation is presented along with the status of desalination in the North Africa countries. Highlights of the national strategies for water resources management is also presented with reference to the major problems projected and recommended solutions. The role of desalination as a viable supplemental resource is, then, analyzed with special attention to the water supply situation, socioeconomic and environmental factors, and developmental trends. Finally, the unique opportunities and challenges associated with desalination in North Africa are discussed with recommendations on preparing for and making the best of these technologies as they become a new way of life in this part of the world.