Efforts to share rivers, lakes and aquifers that cross national boundaries are falling short, raising a growing risk of conflict as global water supplies run low, researchers warned on Thursday, Thomson Reuters Foundation reports.
Fewer than one in three of the world's transboundary rivers and lake basins and just nine of the 350 aquifers that straddle more than one country have cross-border management systems in place, according to a new index by the Economist Intelligence Unit.
With more than half the world's population likely to live in water-scarce areas by 2050 and 40 per cent dependent on transboundary water, that is a growing threat, said Matus Samel, a public policy consultant with the Economist Intelligence Unit.
"Most transboundary basins are peaceful, but the trend is that we are seeing more and more tensions and conflict arising," he told the Thomson Reuters Foundation.
When work began on the index, which looks at five key river basins around the world from the Mekong to the Amazon, researchers thought they would see hints of future problems rather than current ones, Samel said.
Instead, they found water scarcity was becoming a "very urgent" issue, he said. "It surprised me personally the urgency of some of the situation some of these basins are facing."
Population growth, climate change, economic and agricultural expansion and deforestation are all placing greater pressures on the world's limited supplies of water, scientists say.
As competition grows, some regions have put in place relatively effective bodies to try to share water fairly, the Economist Intelligence Unit report said.
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Despite worsening drought, the Senegal River basin, shared by West African nations including Senegal, Mali and Mauritania, has held together a regional water-governance body that has attracted investment and support, Samel said.
Efforts to jointly govern the Sava River basin, which crosses many of the once warring nations of the former Yugoslavia in southeast Europe, have also been largely successful, he said.
But replicating that is likely to be "a huge challenge" in conflict-hit basins, such as along the Tigris and Euphrates rivers in Iraq and Syria, Samel said.
Still, even in tough political situations, "there are ways … countries and local governments and others can work together to make sure conflicts do not emerge and do not escalate," he said.
"The benefits of cooperation go way beyond direct access to drinking water," he said. "It's about creating trust and channels for communication that might not otherwise exist."
The report suggests national leaders make water security a priority now, link water policy to other national policies, from agriculture to trade, and put in place water-sharing institutions early.
"There are no easy solutions or universal solutions," Samel warned. "But there are lessons regions and basins can learn and share."
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The index has yet to examine many hotspots, from the Nile River and Lake Chad in Africa to the Indus river system in India and Pakistan, but Samel said it would be expanded in coming years.
Working toward better shared water management is particularly crucial as climate change brings more drought, floods and other water extremes, said Alan Nicol, who is based in Ethiopia for the International Water Management Institute.
"Knowing how a system works effectively helps you know what to do in the face of a massive drought or flood event – and we should expect more extreme weather," he said.
While efforts to coordinate water policy with other national and regional policies and priorities are crucial, the key missing element in shoring up water security is political will, he said.
"We've been talking about this kind of integrated water management for 30 years," he said. "The problem is practising it. And that's essentially a political problem."