Global water problem

One in three people is enduring one form or another of water scarcity, according to a new report from the International Water Management Institute (IWMI).

The assessment, carried out by 700 experts from around the world over the last five years, was released at World Water Week in Stockholm, a conference exploring the management of global water resources.
The scarcity figures were higher than previous estimates.

"Worrisome predictions in 2000 had forecast that one third of the world population would be affected by water scarcity by 2025. Our findings from the just-concluded research show the situation to be even worse," says Frank Rijsberman, Director General of the International Water Management Institute (IWMI). "Already in 2005, more than a third of the world population is affected by water scarcity. We will have to change business as usual in order to deal with growing scarcity water crisis we see in some countries like India, China, and the Colorado River basin of USA and Mexico."
The report says that about one-quarter of the world's population lives in areas where water is physically scarce, while about one-sixth of humanity -- over a billion people -- live where water is economically scarce, or places where "water is available in rivers and aquifers, but the infrastructure is lacking to make this water available to people."

The report states that access to reliable, safe and affordable water is key to poverty alleviation efforts and warns that declining groundwater supplies, loss of water rights and access, pollution, flooding and drought could well worsen poverty in many areas. Addressing these issues will be critical to raising the quality of life in poor regions.

"To feed the growing population and reduce malnourishment, the world has three choices," said David Molden who led the Comprehensive Assessment says. "Expand irrigation by diverting more water to agriculture and building more dams, at a major cost to the environment; expand the area under rain-fed agriculture at the expense of natural areas through massive deforestation and other habitat destruction; Or do more with the water we already use. We must grow more crop per drop, more meat and milk per drop, and more fish per drop."

Increasing agricultural yields per unit water used is possible through simple, low-cost measures said the report, citing work done in the Brazilian cerrado, or grassland. The report says that similar methods could be used to boost water productivity in the savannahs of Africa where the bulk of people rely on rain-fed agriculture. Other innovative approaches include the more effective use of waste water and streamlined irrigation systems to reduce water waste.
The report notes that consequences of water scarcity are already evident in some of countries. It says that Egypt imports more than half of its food due to a lack of water to grow, while Australia faces major water scarcity in the Murray-Darling Basin as a result of agricultural diversion.

Agriculture is a significant cause of water scarcity in much of the world since crop production requires up to 70 times more water than is used in drinking and other domestic purposes. The report says that a rule of thumb is that each calorie consumed as food requires about one liter of water to produce.

While the report argues that "many difficult choices entailing tradeoffs between city and agriculture users, between food production and the environment, and between fishers and farmers" it says that "the world is not 'running out' of water" and that there is enough land, water and human capacity to solve the shortages.

"The Assessment shows that while a third of the world population faces water scarcity, it is not because there is not enough water to go round, but because of choices people make," Molden said. "It is possible to reduce water scarcity, feed people and address poverty, but the key trade-off is with the environment. People and their governments will face some tough decisions on how to allocate and manage water. Not all situations are going to be a win-win for the parties involved, and in most cases there are winners and losers. If you don't consciously debate and make tough choices, more people, especially the poor, and the environment will continue to pay the price."

Source : http://news.mongabay.com/2006/0821-water.html