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| SUSTAINING WATER LIFELINES - by Lothar Wedekind, based on reports by Yuecel Yurtsever, David Fischer, and Royal Kastens
Behind the numbers are special problems in growing population and industrial areas. There, pressures on resources are mounting, and freshwater often has to be transported from dammed reservoirs far away, or carried in vessels from distant wells. In many areas, local rivers and groundwater are new homes of chemical and other sources of pollution. For the IAEA's technical support cadre, the realities are confronted on local, national, and regional levels in more and more countries. Work has correspondingly intensified over the past decade to sharpen capabilities for assessing, monitoring, and preserving water resources with the tools of isotope hydrology. Central aims have been to assist water authorities in using these techniques to improve the efficiency of water use, identify and prevent sources of pollution, and map the birth and life expectancy of groundwater resources. Some 150 technical cooperation projects totalling $19 million were put into action over the past decade to assist altogether sixty-three countries in water-related areas. In the process, more than 550 young scientists have been trained to apply isotopes in investigations to improve the management of water and other natural resources in these countries. At the same time, countries have renewed their interest in technologies for producing more water, specifically in the use of nuclear energy for desalting seawater, an old atomic dream that is nearing tests of the marketplace again. (See box.)
A large part of the earth's water resources is not safe, clean or renewable, and finding new reserves is costly. Often, the technology is not yet at hand to economically exploit potential resources locked deep inside the earth's crust. Experts say that greater steps are needed to conserve and use water more efficiently, and IAEA-supported research is leading to some solutions in agricultural fields. (See report.) Other water-saving measures include improving irrigation techniques and preventing water losses as high as forty percent from transportation, distribution, and storage systems. At the core of solutions stands our knowledge of earth's water cycle, and how freshwater resources are renewed. A longstanding network of monitoring stations the IAEA runs with the World Meteorological Organization collects key data on the isotope content of rainwater. They are used for regional and global circulation models. Analysts can investigate how the earth's changing climate affects the sustainability of our water resources. The pioneering databank today serves as a global reservoir of pooled knowledge that can lead to greater understanding of how earth's dynamic cycles recreate and renew our water supplies. Strides have been made to bring water to more people. By 1997, the world's collective efforts in the 1990s had given nearly 800 million more people access to safe drinking water. |
Faces around the world visibly frame the imperative of sustaining our freshwater resources:
Economics are changing - water is an increasingly expensive commodity - and the technology is advancing rapidly. As water needs mount in large regions of the world, experts over the past decade have started looking more closely at systems to tap abundant oceans and seas. Among the candidates are facilities coupled to nuclear power plants that produce the electricity for the energy-intensive process of desalting seawater. The idea is not new: nuclear desalination was explored decades ago, and demonstrated in Japan and Kazakhstan. But for the wider water marketplace, it was too expensive. The method still is costly, but the gap is closing. Costs generally have become competitive with those of alternative desalination systems using other sources of energy supply.