Copenhagen climate summit: Nearly half the world will suffer from water shortages 'within 30 years'

Global leaders gathering at the Copenhagen climate change summit urgently need to address the fact that 40pc of the world will suffer from water shortages within 30 years, according to the chief executive of Suez Environnement, Europe's second biggest water company.

Jean-Louis Chaussade, who runs the owner of Bristol Water and Sita UK, the waste management giant, said Australia, the south-west US and Spain would be among the developed countries with inadequate water to meet demand.

Out of the developing areas, the Middle East, North Africa, China and India, would not have enough water to feed their populations or meet agricultural needs.

Wide-scale construction of desalination plants to convert sea into drinking water may be an extreme solution required secure the world's supply, adding to the long list of major infrastructure investments for water companies, he said.

"Over the past 20 years businesses have made major gains in the productivity of labour and capital, but until now they have neglected the productivity of resources," he said.

"There are many opportunities to reduce environmental impacts and simultaneously make considerable savings. Besides greater agricultural water efficiency, the saving of municipal water is a highly productive option," he added.

He said the world would have to think seriously about how to drive more efficiencies, while treating waste water for use in irrigation and industrial purposes would become a priority.

Earlier this year, scientists and experts at World Water Week urged world leaders to include strategies for global water management in the planned Copenhagen climate agreement.

Experts believe that changing weather patterns cause by climate change could affect water supplies, changing conditions for farming, energy production, forestry and industry.

"At the moment the water issue doesn't get enough attention in the climate negotiations," Anders Berntell, head of the Stockholm International Water Institute, said at the conference.

"To be effective, climate negotiations must factor in the impact and importance of water for the world and, indeed, human wellbeing."