Here’s where water is running out in the world — and why

 A growing population and rising temperatures will strain the world’s freshwater supplies over the next 30 years, jeopardizing available water for drinking, bathing and growing food, according to new research.An analysis of newly released data from the World Resources Institute (WRI) shows that by 2050 an additional billion people will be living in arid areas and regions with high water stress, where at least 40 percent of the renewable water supply is consumed each year. Two-fifths of the world’s population — 3.3 billion people in total — currently live in such areas.

South Asia is the most densely populated region experiencing water stress. As the population continues to grow, water demand will continue to increase.

Half of Spain’s land area is used for agriculture, but droughts and searing temperatures have led to crop failures. Reservoir levels in the northeast region of Catalonia are so low that some municipalities are trucking in water to make sure residents have enough for daily life.

Arizona, New Mexico, Colorado, Nebraska, California and Idaho are using more water than they receive each year, depleting groundwater reserves to support farming and industrial use.

Growing and feeding a cow to create one pound of beef requires as much as 1,800 gallons of water, by some estimates. Calorie-for-calorie, that’s almost eight times as much water as vegetables and 20 times as much water as cereals like wheat and corn.

Water-intensive crops like sugar cane and cotton could also drive demand in sub-Saharan Africa, where water use is expected to double over the next 20 years. Many areas still lack infrastructure to reliably deliver water for irrigation. As those pipelines are built, more farmers will have access to water, which will further strain surface water supplies. Inefficient water use and unsustainable management could lower gross domestic product in the region by 6 percent, according to WRI.

The WRI analysis accounts for surface water, but not groundwater stores that are tapped when lakes, rivers and reservoirs run dry. This means the new estimates may underestimate risk. Many rural areas use groundwater for drinking water and farmers worldwide rely on it for irrigation. But groundwater often replenishes much more slowly than surface water...more