13/03/2006 - Gland, Switzerland
– Most of the world’s largest rivers are
losing their connection to the sea, with
nearly a quarter of those left risk being
disconnected in the next 15 years.
According to a new WWF report, only a third
of the world’s 177 large rivers (1,000km
and longer) remain free-flowing, unimpeded
by dams or other barriers. Only 21 of these
actually run freely from source to sea,
the other 43 are large tributaries of rivers
such as the Congo, Amazon and Lena.
The report, Free-flowing rivers – Economic
luxury or ecological necessity? – shows
that the ever increasing loss of free-flowing
rivers is a disturbing trend, threatening
the supply of water for drinking, sanitation,
agriculture, fish and fishery products.
“With so few long free- flowing rivers
left, we are on the brink of losing another
natural phenomenon without fully understanding
the costs of these losses before it’s too
late,” says Ute Collier, WWF's Dams &
Water Infrastructure Programme Manager and
co-author of the report.
According to WWF, the threat to wildlife
through damming rivers cannot be understated.
Large catfish populations in the Amazon
and Mekong Basins, river dolphins in the
Ganges Basin and wildebeest in the Mara
River are all under threat from the effects
of man-made barriers on these rivers.
Dams can reduce the numbers of native fish
in a river, directly affecting fisheries
productivity both upstream and downstream.
Free-flowing rivers also regulate pollution
and sediment levels, the lack of which was
tragically highlighted by the flooding of
New Orleans following Hurricane Katrina.
“Hurricane Katrina was a powerful reminder
of the backlash from altered rivers such
as the Mississippi,” says Jamie Pittock,
Director of WWF’s Global Freshwater Programme.
“Loss of the sediment needed to sustain
coastal wetlands due to upstream damming
and canalization of the river is a major
factor in the devastation and loss of life.”
Most large free-flowing rivers are found
in Asia, followed by South and North America.
Elsewhere, the Australia–Pacific region
has the fewest, with just three, and in
Europe, including areas west of the Ural
River, only one large river, the Pechora
in Russia, remains free-flowing from source
to sea.
As the 4th World Water Forum gets underway
in Mexico (March 16-22), WWF is calling
on governments to better protect the remaining
free-flowing rivers and to apply the recommendations
of the World Commission on Dams.
END NOTES:
• The WWF report, Free-flowing rivers –
Economic luxury or ecological necessity?,
defines a free-flowing river as any river
that flows undisturbed from its source to
its mouth, at either the coast, an inland
sea or at the confluence with a larger river,
without encountering any dams, weirs or
barrages and without being hemmed in by
dykes or levees.
