Shortage of water is a key issue in much of Sub-Saharan Africa. Eleven Sub-Saharan countries are listed as water scarce today and four more are expected to become so by the year 2000. Hundreds of millions of dollars are being invested in new water supplies across Africa. Current water investment budgets in South Africa and Zimbabwe alone exceed US $175 million. However, results are often disappointing, and management problems remain the single greatest cause of misallocation and waste according to the World Bank Policy Paper on Water Resource Management.
Sound decisions about water management require detailed technical information, especially in the context of the large investments and the time critical actions necessary. Inadequate and unreliable data constitute a major limitation for development. Proactive resource planning, based on thorough assessment, is essential to ensure that the future resource base is not degraded or that the existing resources are rationally used. Isotopes can provide unique information on recharge rates and locations of recharge, mixing of water bodies, and sources of salinization, especially in arid and semi-arid areas.
Isotopes also provide independent data useful for constraining and validating groundwater models used for water management. Such information is seldom available from conventional hydrogeological investigations, the only means available to most developing nations, but is essential for determining the long term productive capacity of an aquifer, protecting sensitive recharge areas from pollution, or limiting salt water intrusion. An enhanced regional capacity to apply isotope techniques in an integrated manner with conventional hydrogeological tools will help prevent overexploitation and degradation of groundwater resources.
Recognizing the indispensable role of isotope techniques in understanding the nature of many of these problems, several African countries sought the Agency's assistance. Areas have been identified in each country by end users where adequate assessment of scarce water resources is crucial to the water supply of large population centers and development activities.