Saturday, July 23, 2016

What You Need to Know About the World's Water Wars

Underground water is being pumped so aggressively around the globe that land is sinking, civil wars are being waged, and agriculture is being transformed.

Groundwater Around The World (Credit: NG Maps. Sources: University Of California, Irvine; Whymap; Margat, 2008; Margat And Van Der Gun, 2013) Click to Enlarge.
Beijing is sinking.

In some neighborhoods, the ground is giving way at a rate of four inches a year as water in the giant aquifer below it is pumped.

The groundwater has been so depleted that China’s capital city, home to more than 20 million people, could face serious disruptions in its rail system, roadways, and building foundations, an international team of scientists concluded earlier this year.  Beijing, despite tapping into the gigantic North China Plain aquifer, is the world’s fifth most water-stressed city and its water problems are likely to get even worse.

Beijing isn’t the only place experiencing subsidence, or sinking, as soil collapses into space created as groundwater is depleted.  Parts of Shanghai, Mexico City, and other cities are sinking, too.  Sections of California’s Central Valley have dropped by a foot, and in some localized areas, by as much as 28 feet.

In some neighborhoods, the ground is giving way at a rate of four inches a year as water in the giant aquifer below it is pumped.

Richard Damania, a lead economist at the World Bank, predicts that without adequate water supplies, economic growth in the most stressed parts of the world could decline by six percent of GDP.  His findings conclude that the most severe impacts of climate change will deplete water supplies.

“If you are in a dry area, you are going to get a lot less rainfall.  Run-off is declining,” he says. “People are turning to groundwater in a very, very big way.”

But few things are more difficult to control than groundwater pumping, Damania says.  In the United States, farmers are withdrawing water at unsustainable rates from the High Plains, or Ogallala Aquifer, even though they have been aware of the threat for six decades.

“What you have in developing countries is a large number of small farmers pumping.  Given that these guys are earning so little, there is very little you can do to control it,” Damania says. “And you are, literally, in a race to the bottom.”

As regions and nations run short of water, Damania says, economic growth will decline and food prices will spike, raising the risk of violent conflict and waves of large migrations.  Unrest in Yemen, which heavily taps into groundwater and which experienced water riots in 2009, is rooted in a water crisis.  Experts say water scarcity also helped destabilize Syria and launch its civil war.  Jordan, which relies on aquifers as its only source of water, is even more water-stressed now that more than a half-million Syrian refugees arrived.

Jay Famiglietti, lead scientist on a 2015 study using NASA satellites to record changes in the world’s 37 largest aquifers, says that the ones under the greatest threat are in the most heavily populated areas.

"Without sustainable groundwater reserves, global security is at far greater risk,” he says.  “As the dry parts are getting drier, we will rely on groundwater even more heavily.  The implications are just staggering and really need to be discussed at the international level.”

Read more at What You Need to Know About the World's Water Wars

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