BBC Homepage World Service Education Close Ogallala Aquifier Mexico City Catalonia West Africa Turkey Middle East Aral Sea The Nile Zambezi River Basin The Ganges Yellow River Southern Australia
BBC Links
feedback | help
BBC News
Front Page | World | World Water Crisis 
World water crisis
Click on flashpoints to see close-up map
World map
The world's supply of fresh water is running out. Already one person in five has no access to safe drinking water. Click on the map to read about some of the world's water flashpoints.

Ogallala AquifierNinety-five percent of the United States' fresh water is underground. As farmers in the Texan High Plains pump groundwater faster than rain replenishes it, the water tables are dropping. North America's largest aquifer, the Ogallala, is being depleted at a rate of 12 billion cubic metres (bcm) a year. Total depletion to date amounts to some 325 bcm, a volume equal to the annual flow of 18 Colorado Rivers. The Ogallala stretches from Texas to South Dakota, and waters one fifth of US irrigated land. Many farmers in the High Plains are now turning away from irrigated agriculture, as they become aware of the hazards of overpumping, and realise water is not in endless supply.
Back to top
Mexico CityMexico city is sinking because of the amount of water being pumped out from beneath its foundations. One of the largest and most populous cities in the world, it was once a lush land of lakes. But over the last 500 years the lakes have been drained and the surrounding forests chopped down. As the city grew in size, the water problem magnified. With no adequate drainage system, today rainwater mixes with sewage and is used for irrigation. The city is now at serious risk of running out of clean water. An estimated 40% of the city's water is lost through leaky pipes built at the turn of the century.
Back to top
CataloniaMore than half of Europe's cities are exploiting groundwater at unsustainable rates. Chronic water shortages are already affecting 4.5m people in Catalonia, where authorities are pressing for the construction of a pipeline to divert water from the Rhone in France to Barcelona.
Back to top
West AfricaWhen the water levels of Africa's huge rivers drop, whole economies suffer. Ghana, for example, has become totally reliant on the hydro-electric output of the Akosombo dam on the river Volta. Mali - one of the poorest countries on the planet - is dependent on the river Niger, which flows from Guinea through Mali to Nigeria, for food, water and transport. But great stretches of the river are now facing environmental catastrophe as a result of pollution. In Nigeria, half the population has no access to clean water, and as in much of Africa, many women walk for hours a day to fetch it.
Back to top
TurkeyTurkey has been accused by Syria and Iraq of depriving them of much-needed water, as it continues to build a series of dams along the Euphrates and Tigris. It is also embarking on an ambitious project to sell water from its Manavgat river across the Middle East.
Related Feature: Turkish dam controversy
Back to top
Middle EastWater is the most precious resource in the Middle East, more important even than oil. Competition for water from the River Jordan was a major cause of the 1967 war. As populations increase, water becomes more scarce, aggravating regional tensions. The Lebanese have long accused Israel of having designs on the waters of the River Litani, and Syria accuses it of being reluctant to withdraw from the banks of the Sea of Galilee, the source of up to 30% of Israel's water. Israelis in the West Bank use four times as much water as their Palestinian neighbours.
Back to top
Aral SeaThe Aral Sea in Central Asia was once the world's fourth biggest inland sea, and one of the world's most fertile regions. But economic mismanagement has turned the area into a toxic desert. The two rivers feeding the sea, the Amu Darya and the Syr Darya, were diverted in a Soviet scheme to grow cotton in the desert. Between 1962 and 1994, the level of the Aral Sea fell by 16 metres. The surrounding region now has one of the highest infant mortality in the world, and anaemia and cancers caused by chemicals blowing off the dried sea bed are common.
Related Feature: The Aral Sea tragedy
Back to top
The NileA United Nations report predicts that access to water may be the single biggest cause of conflict and war in Africa in the next 25 years. Such wars are most likely to be in countries where rivers or lakes are shared by more than one country. There is already fierce national competition over water for irrigation and power generation - most notably in the Nile river basin. Cairo warned in 1991 that it was ready to use force to protect its access to waters of the Nile, which also runs through Ethiopia and Sudan. If the populations of these countries continue to rise, competition for the water could be fierce.
Back to top
Zambezi River BasinThe Zambezi river basin in southern Africa is one of the most overused river systems in the world. Although the countries through which the river flows usually vie with each other to harness the water power, at other times they are deluged by floods and heavy rain. The region experienced the worst floods in living memory in March 2000, exacerbated by Zimbabwe opening the Kariba dam gates.
Back to top
The GangesThe most sacred Hindu river, the Ganges, is so depleted that the Sundarban wetlands and mangrove forests of Bangladesh are seriously threatened. It is also said to contain unacceptable levels of arsenic. As more trees are chopped down, and more buildings erected along its banks, the glaciers supplying the river have been melting, raising fears of shortages and drought downstream. The river has been the subject of a long-running dispute between India and Bangladesh, although recently progress has been made in resolving the conflict.
Related Feature: The Ganges: Troubled waters
Back to top
Yellow RiverAll three rivers feeding China's Northern Plain are severely polluted, damaging health and limiting irrigation. The lower reaches of the Yellow river, which feeds China's most important farming region, ran dry for 226 days in 1997. Northern China is home to two thirds of the country's cropland but only one fifth of its water. As competing demands for water are made by cities, industry and agriculture, the land is drying up. Between 1991 and 1996, the water table beneath the north China plain fell by an average of 1.5 metres a year.
Back to top
Southern AustraliaAustralia is the world's driest continent. Settlers have long dreamt of finding a way to turn coastal rivers inland. But an ambitious scheme to reverse the flow of the Snowy River has backfired disastrously, threatening to deprive Adelaide of fresh water. The region that the diverted Snowy River now feeds is bounded by Australia's two longest rivers, the Murray and the Darling. The water tables under this land are now rising, pushing deadly quantities of salt to the surface. The salt has already destroyed some of the country's most productive farmland. The Murray-Darling basin produces three-quarters of Australia's irrigated crops. Many of the basin's tributaries may be unusable for irrigation in 20 years time, let alone as a source of drinking water.
Back to top