With more than one billion people lacking adequate access to freshwater, the world is already experiencing a vast set of challenges. In the not-so-distant future, as the global population continues to grow and as the impacts of climate change are felt, the problem will intensify. In this month’s issue of Scientific American
, Harvard professor Peter Rogers unpacks the multiple factors contributing to this scarcity and proposes six priority actions to alleviate some of this stress.
Rogers’ key message is: “If a crisis arises in the coming decades, it will not be for lack of know-how; it will come from a lack of foresight and from an unwillingness to spend the needed money.” He points out that it is the combination of climate change and continued population growth that will have a devastating affect on local water scarcity. However, water scarcity is not only driven by demand outweighing supply, but also by the pollution of our water supply and by the wasting of water by individuals, industry, and our water-supply systems.
To address these issues, Rogers proposes six priority recommendations:
Rogers lays out a solid set of steps to address our growing water needs, but implementing them will require leadership in the government and beyond, as well as the conscious planning and management of water resources. And while these steps are reasonable for large economies with robust governance systems, the areas of the world that are most affected by a lack of water—places where diarrhea is the leading cause of death for children under five and where women and children are required to walk miles to wells to collect drinking water—will require not only financial support, as Rogers notes, but also long-term technical and legal assistance.
- Set higher prices for water use. In the United States and other developed countries, water is so cheap that “it seems almost free,” so there is little incentive to conserve or reuse. Increasing the price of water supply would drive conservation. For instance, municipalities would be more likely to fix leaks in water-supply systems and to invest in water reuse.
- Improve irrigation efficiency. With approximately 70 percent of available freshwater going to agriculture, increasing the efficiency of irrigation systems—fixing leaks, creating low-loss storage capabilities, and more efficiently applying water to crops—would create a volume of water that could go to other uses.
- Supply “virtual water.” “Virtual water” refers to the amount of water used to produce a product. If arid and semiarid areas imported more food or other water-intensive products, this import of virtual water would allow the limited water that is available to go to other uses, such as drinking water or industry. Implementing this recommendation would require the liberalization of trade in farm products and a reduction in tariffs. Given the highly contested debates about farm subsides in the United States and the EU, this seems a far-off proposition.
- Use dry or low-water devices for sanitation. This would reduce the amount of water used for sanitation and could also reduce the use of fossil fuel-based fertilizers if the solid waste were collected and composted for farming purposes.
- Use desalination to increase supply. Once limited by high costs and high energy demands, desalination technologies are nearing commercial viability.
- Invest in water. Major investment in existing technologies to conserve water, maintain and replace infrastructure, and construct sanitation systems will be needed to stave off a water crisis. According to the article, Booz Allen Hamilton estimates that a $1 trillion annual investment in these sectors will be required to meet the world’s water needs through 2030.