Optimum management of global water resources presents one of the most crucial challenges of the 21st century. Global population will increase by three billion or more over the next 50–75 years, and the number of people living in urban areas will more than double. Most of the world’s population growth will occur in developing countries where water is already critically short and many of the residents are impoverished. Even today, >1 billion people do not have access to safe and affordable drinking water and perhaps twice that many lack adequate sanitation services. In fact, inadequate drinking water quality is a leading cause of infant mortality worldwide.
Food production may soon be limited by water availability. Agricultural water use is not sustainable in many locales around the world for reasons that include soil salinization, ground water overdraft, and the overallocation of available surface water supplies. This situation raises questions about whether there are sufficient water resources to support the existing population on a long-term basis, to say nothing of the significantly larger population that will have to be fed in the remaining decades of this century.
Intensifying competition for water resources by agricultural, industrial, and domestic users has led to a sharp increase in stress on aquatic and wetland ecosystems. Moreover, the inadequacy of environmental water supplies in much of the world has been significantly exacerbated by declining trends in water quality. Many developed countries have addressed this problem by adopting laws to guarantee supplies for the environment, but such guarantees are contingent on having adequate water for urban needs and on the availability of sufficient quantities of food. No such guarantees can be provided in developing countries, which tend to neglect environmental needs and are unable to mount efforts to maintain and enhance water quality for financial reasons.
There seems to be little doubt that science and technology must play a vital role in devising the solutions that will be necessary to overcome the daunting problems arising from global water scarcity. This article summarizes the presentations of 16 internationally renowned water experts and the associated discussions that constituted the Arthur M. Sackler Colloquium entitled The Role of Science in Solving the Earth’s Emerging Water Problems. The Colloquium was held on October 8–10, 2004, at the Arnold and Mabel Beckman Center of the National Academies of Sciences and Engineering in Irvine, CA. It attracted an audience of ≈100 that participated in wide-ranging discussions. The names of the water experts and the titles of their presentations are included on the NAS web site at www.nasonline.org/water. In addition, many of the presentations may be viewed online at the NAS web site.
In the next section of the article, present and future global water problems are characterized. Prospects for finding science-based solutions to these problems are discussed in the following section, and a third and concluding section offers some findings and recommendations about the role of science in addressing the world’s water problems.
Reference: https://www.pnas.org/content/102/44/15715
