Asia, US plains facing water extraction crisis

Aug 08, 2012
Corn plants struggle to survive in a drought-stricken farm field on August 7, in Collins, Iowa. Heavily-populated regions of Asia, the arid Middle East and parts of the US corn belt are dangerously over-exploiting their underground water supplies, according to a study published on Wednesday in the journal Nature.

Heavily-populated regions of Asia, the arid Middle East and parts of the US corn belt are dangerously over-exploiting their underground water supplies, according to a study published on Wednesday in the journal Nature.

"The countries that are overusing most significantly are the United States, India, China, Pakistan, Iran, Saudi Arabia and Mexico, and the highest number of people that are impacted by this live in India and China," Canadian hydrologist Tom Gleeson told AFP.

"Over a quarter of the world's population live in these regions where groundwater is being overused," he said in a phone interview.

Many places are rapidly pumping out "fossil" water, or water that was laid down sometimes thousands of years ago and cannot be replaced on a human timescale.

Seeking a yardstick of sustainability, the study creates a measure called the groundwater footprint.

It calculates the area of land sustained by extracted water and compares this to the size of the aquifer beneath.

The global groundwater footprint is a whopping 3.5 times the size of the world's aquifers, the study found.

However, this stress is accounted for by a small number of countries.

For instance, in the South Caspian region of northern Iran, the footprint is 98 times the size of the aquifer; in the Upper Ganges in India and Pakistan, it is 54; while in the US High Plains, the figure is nine.

"Humans are over-exploiting groundwater in many large aquifers that are crucial to agriculture, especially in North America and Asia," said Gleeson.

"Irrigation for agriculture is largely causing the problem but it is already impacting in some regions the ability to use groundwater for irrigation, so it is almost like a self-reinforcing problem."

The study aims at adding a new analytical tool to help policymakers cope with the world's intensifying water problems.

In March, the UN warned in its Fourth World Water Report that water problems in many parts of the world were chronic, and without a crackdown on wastage would worsen as demand for food rises and climate change intensifies.

By 2050, agricultural use of water will rise by nearly 20 percent, on the basis of current farming methods, to meet food demands from a population set to rise from seven billion today more than nine billion.

Gleeson, a specialist at McGill University in Montreal, Canada, used a computer model in collaboration with scientists at Utrecht University in the Netherlands and crunched national statistics on water use. The next step will be to use satellite data, which should be a more reliable source, he said.

Water from surface sources -- rivers and lakes -- is well documented, but use of aquifers is poorly understood.

According to the UN report, extraction from aquifers has tripled in the past 50 years and now accounts for nearly half of all drinking today. But how this use breaks down in finer detail, notably its impact on the watersheds that feed rivers, is less well known.

Explore further: Pacific leaders say climate will claim entire nations

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baudrunner
2.4 / 5 (9) Aug 08, 2012
Almost all of the runoff from the Himalayas through Pakistan is wasted because it is allowed to escape into the sea with no human intervention. Pakistan could be the breadbasket of the entire Eastern Hemisphere, but through mismanagement and a corrupt administration that ain't gonna happen any time soon. America's water problems could be easily solved by constructing underground aqua-ducts and cisterns filled with water channeled from Canada. Canada is just a huge wetlands.
Scottingham
3.5 / 5 (4) Aug 08, 2012
Indoor farms use 10% of the water outdoor ones do. Also, no need for pesticides.

Of course, it is much more energy intensive. I think that is a safe tradeoff given the increase in food security it would provide (bad weather is a thing of the past)
ziphead
1.8 / 5 (5) Aug 08, 2012
Not long now, boys and girls.

... But fear not; Mel Gibson will save us all on his forth comming...
DavidW
2.3 / 5 (3) Aug 08, 2012
The biggest unnecessary use of drinking water is raising livestock for human consumption. Same goes for produce fed to animals for human consumption, as that's a 20 to 1 waste factor.
Pattern_chaser
Aug 09, 2012
This comment has been removed by a moderator.
alfie_null
1 / 5 (1) Aug 09, 2012
"and without a crackdown on wastage would worsen as demand for food rises and climate change intensifies."
Won't plain old economics correct the problem? Otherwise what? Allocating and rationing water supplies? That sounds like a bad idea on several levels.
physyD
1 / 5 (1) Aug 09, 2012
They could build desalination plants. There are a couple versions and some can deliver a few million gallons a day. As for the brine left over they can say it will help counter the melting ice of global warming... I mention this because some claim that is will make the sea saltier, too salty (As the case of the Perth Australia desalination plant)
antialias_physorg
1 / 5 (1) Aug 09, 2012
Won't plain old economics correct the problem?

When was the last time 'plain old economics' corrected an environmental problem?
(Hint: It starts with 'n' and ends with 'ever')

They could build desalination plants

Ever tried to drink water that comes out of a desalination plant? While technically of 'drinking water quality' it's not a very pleasurable experience.

rubberman
1 / 5 (1) Aug 09, 2012
Almost all of the runoff from the Himalayas through Pakistan is wasted because it is allowed to escape into the sea with no human intervention. Pakistan could be the breadbasket of the entire Eastern Hemisphere, but through mismanagement and a corrupt administration that ain't gonna happen any time soon. America's water problems could be easily solved by constructing underground aqua-ducts and cisterns filled with water channeled from Canada. Canada is just a huge wetlands.


Sorry...were gonna need that water for bitumen extraction and irrigation of "the new bread basket" for the west. Plus China is bidding higher per gallon for what we deem sellable. Perhaps when water is more important than bombs some of that 600 billion dollar military budget can be re-allocated to saving lives instead of taking them.....
Maggnus
1 / 5 (1) Aug 10, 2012
Almost all of the runoff from the Himalayas through Pakistan is wasted because it is allowed to escape into the sea with no human intervention. Pakistan could be the breadbasket of the entire Eastern Hemisphere, but through mismanagement and a corrupt administration that ain't gonna happen any time soon.


This is a serious over-simplification to the point the comment is almost laughable. Maybe not even almost.

America's water problems could be easily solved by constructing underground aqua-ducts and cisterns filled with water channeled from Canada. Canada is just a huge wetlands.


This comment shows an arrogance combined with such a deep ingnorance I have to shake my head. As a Canadian, I can tell you we are not "just a huge wetland" and even if we were, what makes you think we would allow the US to just channel our water there?

The US midwest is in the process of turning into a desert. It is going to take a hell of a lot more effort to prevent or at least mitiga
Maggnus
1 / 5 (1) Aug 10, 2012
cont...

mitigate the loss of all of that land then some simpleton knee-jerk responce.
SatanLover
Aug 10, 2012
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