Libya's choices: Desalination or the Great Man-Made River Project

At the beginning of the 1980s Libya decided to develop the Great Man-made R iver Project (GMRP) to provide water to its population. The GMRP is one of the largest civil engineering projects in the world, involving the abstract ion of ancient groundwater from the Sahara Desert and the transportation of water over hundreds of kilometers to the coast of Libya where demands for water exist. In support of decisions regarding further investments in Libya 's water supply systems, an economic analysis has been performed. This arti cle summarizes the methods and results of the study. The study identified l east-cost combinations of investments in the GMRP together with desalinatio n that would meet specified water demand targets at various demand sites in the country. The results indicate that, due to the investments already mad e in the GMRP, desalination only appears to be an economically efficient ex pansion alternative under most optimistic cost scenarios for desalination p lants, and then only for a limited range of water demands. Another interest ing finding is a significant uncertainty concerning well field capacity sch eduling over time, a finding which warrants additional studies focusing on capacity expansion over time. In addition to economic aspects, information on other water related issues and viewpoints seems to be very relevant to d ecision making on the future of Libya's water supply situation as well as t o other large scale water conveyance projects. (C) 1999 Elsevier Science Lt d. All rights reserved.