In many parts of the world, there are simply no more conventional freshwater resources available to meet growing demand. Beyond limiting economic development, the lack of sufficient freshwater resources threatens the well-being of billions of people by causing conflict, social unrest and migration. The only way to address this challenge is by radically rethinking water-resource planning and management in a way that emphasizes the creative exploitation of unconventional water sources.
There is a large and growing number of unconventional sources of freshwater with massive potential, beginning with desalinated seawater or highly brackish groundwater. Already, there are 18,000 desalination facilities in more than 100 countries producing roughly 32 billion cubic meters of fresh water — about one-third of the volume passing over Niagara Falls annually.
Some 44 percent of global desalinated-water production is taking place in the Middle East and North Africa, and new facilities are being built across Asia, the United States and Latin America. Annual desalination capacity worldwide is increasing by 7 to 9 percent on average.