By Lynn Novelli

A report by the World Bank warns that we should prepare now to mitigate climate change-induced water scarcity by 2035 or prepare to pay the human, environmental, and economic price.



June 28, 2016—Water scarcity has the potential to negatively impact food, energy, and urban and environmental systems, according to the report "High and Dry: Water, Climate Change, and the Economy," recently released by the World Bank Group and authored by its lead economist, Richard Damania, Ph.D. The stakes are particularly high in developing countries; sophisticated economic models suggest that water scarcity could lead to a decline in gross domestic product (GDP) of as much as 6 percent in the Middle East, North Africa, Central Asia, and parts of South Asia if water scarcity is not addressed.

"Most of the impact of climate change will be mediated by water," Damania says. Changes in precipitation, droughts, rising temperatures, and the frequency and severity of storms—combined with population growth, expanding urbanization, and the corresponding increased demand for water—will exacerbate water scarcity in high-risk regions across the world, he explains. "Continuing poor water management based on current policies and processes ultimately will stress agriculture, human health, and production, resulting in slower economic growth in these regions."

North and South America and Europe, which currently enjoy a plentiful supply of water, are not immune to future scarcity-induced challenges either, according to the World Bank's report. A galloping rise in demand for water—50 percent more for agriculture, 50 to 70 percent more for urban uses, and 85 percent more for the energy sector—will combine with the effects of climate change to produce a disturbing hydrological and economic future for developed nations, the report states.

"The problem is not the total volume of water but its uneven distribution," Damania stresses. "The hydrologic cycle is a closed system." The challenge will be to balance the rapidly growing demand for water worldwide with the availability of supply.

On the plus side, Damania believes that wiser management of water resources can mitigate some of the effects of climate change on humans, the environment, and the world economy. He predicts that significant investment in water infrastructure and technology will be integral to the success of new water management strategies related to allocation, efficiency, and a reduction in the variability of supplies.

Although these needs are universal, they are critical in developing countries in which, Damania says, the infrastructure gap for water storage, flood control, and energy supply is "massive." He adds that these countries historically have been prone to skimping on short-term maintenance of water-related assets, which shortens the facilities' service lives and increases the risk of water crises in these regions.

Water infrastructure requirements worldwide should create opportunities for repair and maintenance, new construction, and technological advances. In fact, Damania says that the window of opportunity already is open. "It is an evolving window of opportunity, and change will be ongoing because there is so much variability," he says.

The first priority for more responsible water stewardship should be reducing water loss through an aggressive infrastructure repair and maintenance program, Damania says. The problem of aging public water system pipes is virtually global, affecting major cities in developed countries as well as many other regions across the globe. "In many areas, pipes leak more water than they deliver to households," he says. "Not only are the pipes old, in many regions of the world, the government doesn't even know where they are." According to his research, a staggering 32 billion m 3 of treated water is lost to urban water systems worldwide each year through physical leaks in the pipes and more than half of this loss occurs in developing countries.

Beyond repairing existing infrastructure, new infrastructure construction aimed at increasing water supplies will be the linchpin of climate change mitigation, according to the World Bank. In most regions of the world, reservoirs and their associated dams are the primary structures used to increase supply. The current global water storage capacity is 6.2 km 3 , distributed across approximately 6,800 reservoirs and dams, according to the National Oceanic and Atmospheric Association. "Expanding water infrastructure worldwide already is happening at a rapid pace," Damania says. "The goal is to nearly double storage volume by 2035. Approximately 3,800 new dams are being planned, and construction that will increase volume by 22 percent is under way." New construction will increase the number of dams by 16 percent over the next 15 years.

Dams also regulate water flow and can protect cities in river basins from floods, the World Bank report stresses. For coastal areas, construction of levees and seawalls is critical to preventing flood damage to cities caused by storms.

Damania also factors technological advances into the water risk mitigation model, although he notes that innovation is needed to improve the efficiencies of such technologies as desalination and wastewater recycling. "Desalination and wastewater recovery currently are both highly energy-intensive and inefficient," he says. "With the high cost of these technologies, they are not economically viable for lower-value uses such as crop irrigation. Technologic innovation is necessary to bring down the price."

The ultimate challenge for every country and region of the world over the next 15 to 20 years, the report stresses, will be to advance infrastructure, technology, and innovations in ways that do preserve rather than degrade water—the natural resource upon which human and ecological systems all depend.