Pollution, dams, climate change threatenworld's greatest rivers, WWF says


GENEVA — The Yangtze River gets more than half of China's
industrial waste and sewage. Europe's Danube has lost most of its
surrounding wetlands. And the Rio Grande has become so shallow that
salt water is seeping in, bringing ocean fish that threaten
freshwater species.

Pollution, global warming and rampant development could destroy
some of the world's most iconic rivers in the coming decades,
threatening to wipe out thousands of fish species and cause severe
water shortages, the World Wide Fund for Nature said in a report.

Only 21 of the planet's 177 longest rivers run freely from
source to sea, with dams and other construction destroying the
habitats for migratory fish and other species by altering the
water's natural ebb and flow, the WWF said.

About a fifth of the world's 10,000 freshwater fish and plant
species are either extinct or endangered, the report said, calling
on governments to radically step up efforts to preserve rivers,
lakes and wetlands.

"Unabated development is jeopardizing nature's ability to meet
our growing demands,'' said Jamie Pittock, who heads WWF's
freshwater program.

The report focused on some of the world's most important rivers:
the Nile, the Danube, the Rio Grande, South America's La Plata,
Australia's Murray-Darling and Asia's Yangtze, Mekong, Salween, and
Ganges rivers.

The Danube — home to more than half of Europe's fish species — has lost 80 percent of its surrounding wetlands and flood plains
because of dams, the report said.

Construction to ease shipping channels — dredging, pumping water or straightening banks — also threaten animals and plants in the
river, which runs from Germany to the Black Sea, WWF said. Less
than 7 percent of its basin is protected.

In China, pollution in the main stem of the Yangtze River has
increased by more than 70 percent over the last 50 years. Almost
half of the country's industrial waste and sewage is discharged in
the river, the report said.

Garbage heaps, pig waste and discharge from factories, hospitals
and mines — possibly including radioactive waste — lie at the
bottom of the reservoir at the Three Gorges Dam, the world's
largest hydroelectric project, the WFF said.

In the Rio Grande, low water levels have allowed salt water to
enter and ocean species to crowd out freshwater fish. Excessive
extraction, primarily for agriculture, is threatening the river,
which flows along the U.S.-Mexican border.

At the same time, rising populations along both sides of the
river need more and more water, increasing pressure on the 69 fish
species found only in the Rio Grande, the WWF said.

Global warming is threatening fish populations in Africa, where
even small temperature changes can dramatically alter water levels
and fish productivity, the report said.

The Nile, the world's
longest river, is expected to reach a critically low level by 2025,
threatening a source of drinking water for thousands of years.