The overuse of water for farming is the biggest environmental threat
to the world’s freshwater resources and damage is likely to worsen
until 2020, an international report issued on Tuesday said.

The
U.N.-led Global International Waters Assessment, a review compiled by
1,500 experts, also concluded overfishing was the main problem
affecting the health of the oceans.

A leading academic who helped
draw up the report predicted more frequent conflicts over water in the
future as supplies became scarcer.

"Overall, agriculture ranks
highest as the key concern on the freshwater front," the U.N.
Environment Programme said of the conclusions of the report, which also
examined risks such as pollution and global warming until 2020.

"Falls
in river flows, rising saltiness of estuaries, loss of fish and aquatic
plant species and reductions in sediments to the coast are expected to
rise in many areas of the globe by 2020," it said of the side-effects
of irrigation.

"These will in turn intensify farmland losses,
food insecurity and damage to fisheries along with rises in
malnutrition and disease," it said.

In many cases, problems could
be solved by better planning, often simply by growing crops in regions
where they did not demand vast irrigation. The report said that more
dams and deeper wells were not the answer.

It said, for instance,
that dams on the Volga River had reduced the spawning grounds for
Caspian sturgeon, and 90 percent of the water in Namibia’s Eastern
National Water Carrier canal was lost because of evaporation.

By Alister Doyle
Reuters.com