. Death of the World's Rivers & Rivers: A Drying Shame . |
||||
|
Death of the World's Rivers Sunday 12 March 2006 Disaster warning from UN as investigation reveals half of the planet's 500 biggest rivers are seriously depleted or polluted. The world's great rivers are drying up at an alarming rate, with devastating consequences for humanity, animals and the future of the planet. The Independent on Sunday can today reveal that more than half the world's 500 mightiest rivers have been seriously depleted. Some have been reduced to a trickle in what the United Nations will this week warn is a "disaster in the making." From the Nile to China's Yellow River, some of the world's great water systems are now under such pressure that they often fail to deposit their water in the ocean or are interrupted in the course to the sea, with grave consequences for the planet. Adding to the disaster, all of the 20 longer rivers are being disrupted by big dams. One-fifth of all freshwater fish species either face extinction or are already extinct. The Nile and Pakistan's Indus are greatly reduced by the time they reach the sea. Some, such as the Colorado and China's Yellow River, now rarely reach the ocean at all. Others, such as the Jordan and the Rio Grande on the US-Mexico border, are dry for much of their length. Even in Britain, a quarter of the country's 160 chalk rivers and steams - such as the Kennet in Wiltshire, the Darent in Kent, and the Wylye in Wiltshire - are running out of water because too much is being abstracted for homes, industry and agriculture. This week an influential UN report will officially warn the world's governments of an "alarming deterioration" in the planet's rivers, lakes and other freshwater systems. Klaus Toepfer, the executive director of the United Nations Environment Programme, told the IoS yesterday that the state of the world's rivers is "a disaster in the making." The UN's triennial World Water Development Report, compiled for an international conference in Mexico City which opens on Thursday, warns that "we have hugely changed the natural order of rivers worldwide," mainly through giant dams and global warming. Some 45,000 big dams now block the world's rivers, trapping 15 per cent of all the water that used to flow from the land to the sea. Reservoirs now cover almost 1 per cent of land surface. The UN report says that demand for them "will continue to increase," but recommends that they should be barred from the world's remaining, undammed "free-flowing" rivers. The United States has dismantled 465 dams in recent years, mainly for environmental reasons. But last week, in an abrupt U-turn, it signalled that it was about to embark on its biggest dam-building campaign in decades, when the Washington State legislature passed a bill to allow the federal government to build a series of dams on the Columbia, the West's largest river. Global warming is endangering even the rivers that have largely escaped damming. The relatively untamed Amazon was hit by its most serious drought on record last autumn. And salmon are dying in Alaska's Yukon River - the world's longest undammed watercourse - because its waters are getting too hot. On Tuesday an international day of action will see demonstrations across the globe to draw attention to rivers' plight. Rivers:
A Drying Shame Sunday 12 March 2006
The delta of the great Colorado River - where once it swept into the Gulf of California - used to be the most wonder-filled wetland in the whole North American continent. Some 400 species of plants and animals - including jaguars, beaver and the world's smallest dolphin- thronged its 3,000 square miles of wetlands, lagoons and tidal pools. The local people made a good living fishing its teeming waters. Now it has become a forbidding desert of salt flats and giant heaps of dead clamshells. The fishing boats have been long since beached; the destitute people have to seek what work they can in wheat fields and tortilla factories far away. The reason for the transformation is not hard to find. Not a drop of the mighty river which once carved the Grand Canyon now flows through the delta to the sea. It has all been used upstream - to slake the thirst of cities such as Tucson, Arizona, feed fountains in Las Vegas, green golf courses and irrigate farmland. Such water as remains in the delta has flowed in from the sea. It is much the same story in that other great river of the American south-west, the Rio Grande. This does not merely fail to reach the sea: it disappears for much of its length. The atlases tell us it is one of the 20 longest rivers in the world, but in reality it stops some 800 miles inland at El Paso, Texas, which takes all its water. For the next 200 miles or so there is just a dribble of sewage in its old river bed, and even this often dries up in summer. Local people call it "the forgotten river". The dry channel does not come alive again until a relatively healthy tributary, the River Conchos, joins it from Mexico. For the rest of its length, as it forms the boundary between the two nations, it should, in justice, be called the Conchos, not the Rio Grande. But even this is quickly used up, mainly to irrigate farmland, and often fails to make it through to the Gulf of Mexico. It is much the same story right across the world. China's Yellow River, the fifth longest in the world is in trouble at both ends. Its source in the Tibetan plateau is drying up - and for most of the past 35 years it has failed to reach the sea all year round. Similarly, despite the words of the spiritual, the River Jordan is far from "deep and wide". In practice it ends at the Sea of Galilee, where Israeli engineers have blocked the outflow and piped the water to irrigate fields and supply Jerusalem and Tel Aviv. Such water as flows down the Jordan valley again comes from a tributary, the River Yarmuk. But it cannot really do the job. In biblical times the valley carried a billion cubic metres of water every year; now it has to make do with less than a tenth of that. The ugly truth is that the river - sacred to Christians, Jews and Muslims - is now mainly made up of diluted sewage. It is the same for river after famous river. The lower reaches of the Nile used to carry 32 billion cubic metres of water a year; now they are down to two billion. The Indus in Pakistan - "Asia's Nile" - similarly has lost 90 per cent of its water in the last 60 years. Australia's Murray River fails to reach the sea every other year. Even in Europe, Germany's River Elbe has run so dry that it frequently becomes impassable to barge traffic for months at a time - and three years ago river traffic almost completely stopped on the Rhine. In Britain the Environment Agency regularly sounds the alarm about our chalk rivers and streams - which gave birth to the sport of fly-fishing. Dozens of them dry up every summer, and 40 of the 160 in the country are officially under threat. The writer Fred Pearce, who has published a groundbreaking book on the crisis of the world's rivers, says: "The maps in an atlas no longer accord with reality. The old geography lessons about how rivers emerged from mountains, gathered water from tributaries and finally disgorged their bloated flows into the oceans are now fiction." The UN-backed World Commission on Water for the 21st Century reported: "More than one half of the world's major rivers are being seriously depleted and polluted". There are two main culprits; abstraction of water for rivers - usually after damming them - and global warming. The world has, on average, built two giant dams a day, every day, for the past 50 years. Now 45,000 of them span the world's rivers. Every one of the world's 20 longest rivers is encumbered by them. In many ways it all began on the Colorado, 70 years ago, with the Hoover Dam, the great symbol of Franklin Roosevelt's New Deal. Today, the dams intercept more than a third of the world's freshwater as it flows towards the sea and at any one time are holding back 15 per cent of it. The UN's triennial World Water Development Report, published for a international conference in Mexico City this week, cautions that damming has "hugely changed the natural order of rivers worldwide." It goes on: "Humanity has embarked on a huge ecological engineering project with little or no preconception - or indeed full present knowledge - of the consequences. We have sought to redesign and impose a new order on natural planetary systems, built over aeons of time." Dams waste massive amounts of water. In hot, dry regions, they lose about 10 per cent of their reservoirs to evaporation every year: much more is lost in irrigation. Global warming is making things even worse. The source of the Yellow River is drying out as glaciers retreat. And a great drought in the southwestern United States - so intense that even cacti are wilting - is exacerbating the crisis of the Colorado and the Rio Grande. It is even endangering relatively healthy rivers. The Amazon, relatively unencumbered by great dams, was hit by the worst drought on record last year: water levels fell by 10 metres and boats were stranded. And salmon are endangered in Alaska's Yukon River because its waters are too warm. This will only get worse as the world goes on heating up, making the desert delta of the Colorado just a foretaste of the rivers of the future. River Report Amazon
Yellow
River Jordan
Rio
Grande |
||||
. . |