Usable water, not oil, will be next big challenge for global economy

Here’s a question for your next quiz night. How many litres of water are there in a half-litre bottle of any sugar-based carbonated beverage?

This was the query that in 2010 attracted the attention of three scientists in the Water Centre at the University of Twente in the Netherlands.

The university, along with big international players including World Wildlife Fund and the World Bank, is a founding member of Water Footprint, dedicated to connecting and informing "diverse communities interested in sustainability, equitability and efficiency of water use".

In a paper published in the journal Water Resource Management in 2011, the scientists steered clear of naming names, but made clear that the hypothetical drink in question was "realistic".

Most companies, they noted, focused only on their own performance when assessing their water use. What they demonstrated, however, by examining every detail of the process in minute detail, from the growing, harvesting and transporting of the crops to the making of the drink, the plastic bottle it came in and its delivery to market, was that 99 per cent of the water use came from the supply chain.

And the astonishing fact is that producing a single half-litre bottle of fizzy pop consumes between 150 and 300 litres of water, depending on whether the sugar comes from beet grown in the Netherlands or cane produced in Pakistan or Cuba.

And right there in that insane number can be found the central source of the world's water problems: we depend upon it for our existence, but we neither understand nor care how finite a resource it is.

This year has been declared the Year of Water Co-operation by the United Nations and the increasingly fraught subject of H2O will be under the spotlight at numerous conferences and summits around the world.

Tellingly, water will take centre stage at Abu Dhabi's annual World Future Energy Summit, which starts on Tuesday.

On day one, a ministerial panel will discuss the "water-energy nexus", noting that "the global energy sector uses vast amounts of water for fuel production and power generation, accounting for an estimated eight per cent of all freshwater withdrawals [and that] there are already signs that water scarcity may be constraining energy production in many parts of the world".

It is no secret, of course, that the UAE and other countries along the Arabian Gulf are dependent upon desalination for their fresh water - a process that consumes large amounts of energy - and that those nations are developing at a rate that threatens to outpace their ability to generate either enough water or electricity.

Renewables, the panel will suggest, may offer some solutions. But the Earth's hydrological cycle is highly complex. Tinker with one part of the machine and another goes out of whack, and even renewables, while doubtless a partial solution to the world's energy crisis and an area of research and development in which Abu Dhabi is leading the world, pose their own problems.

Take biofuels, an alternative to fossil fuels, derived from crops such as soya, corn or sugarcane. Forget the thirst of fizzy pop: each litre, says the UN, costs an astonishing 2,500 litres of water to produce.

After Abu Dhabi comes Seville, Spain, and April's Global Water Summit. "Water risk," say the organisers, water industry analysts Global Water Intelligence, is "the most important challenge the global economy will face over the next decade", thanks to the triple whammy of climate change, increasing population-driven demand for food and energy and a lack of investment.

Over the next decade, they predict, each of us "will experience a water related event - a shortage, a flood, an infrastructure failure, an interruption to business, an economic disruption - which will have a bigger impact on our lives than we have ever experienced before".

In the end, in other words, our ingenuity will take us only so far. We can work tirelessly, as individuals and nations, to reduce our water footprint but even if we learn how to recycle every drop of water we use, continuing population growth will eventually outpace the Earth's ability to keep all of us alive.