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WATER FOR SALE.....dimwits need not reply.

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Fresh water supplies are going to run out, so what can do to make the taps keep running?

How we manage the rest of this precious resource will dictate the planet's future.

This may seem like a surprising statement, but the world's supply of fresh water is finite. As global population rises, the demand for food and the water that produces it grows inexorably. Globally, farming accounts for 70 per cent of our withdrawals from this fixed "bank account", this in the face of ever-greater domestic and industrial usage.


Water tables are falling in many parts of the world. Himalayan glaciers will shrink massively in the next century, reducing natural water storage in the mountains. The shortfalls will have to come from groundwater and surface storage. Many great rivers have drastically diminished flows.

Bangladesh is suffering from the diversion of Ganges River water and increased salinisation. Underground aquifers in many places are shrinking so rapidly that NASA satellites are detecting changes in the Earth's gravity. The Water Resources Group has estimated that India may face a 50 per cent lag in water availability relative to demand by 2030 and that global availability may lag demand by as much as 40 per cent; the statistics have been questioned. Sixty years ago, the world's population was about 1.25 billion people; few people, even in arid lands, worried about water supplies. Then came the Green Revolution, with its new, high-yielding crops, which depend on fertilisers and a great deal more irrigated farming. Global populations skyrocketed to nearly seven billion by 2009, with a projected nine billion by 2050. By the same year, the five hundred million people living in areas chronically short of water in the year 2000 will have grown by 45 per cent to four billion. A billion of us currently go hungry because there is not enough water to grow food. Much of the world's water is still unpriced, but it is now the most valuable commodity in the world. To compound the problem, 60 per cent of the world's people live in crowded river basins shared by several countries, often with daggers drawn.

The problems are acute, especially in arid areas with growing populations, where boreholes and aquifers are thought to be the answer. Seemingly a miraculous solution, but not if the drawdown exceeds the replenishment rate, as is the case with the ground water beneath a now-sinking Mexico City's 20 million inhabitants and with Bangkok, Buenos Aires and Jakarta, where pollution and rising salt levels combine with overdrafting.

In China, deep groundwater levels have dropped as much as 295ft (90m) in places. We have perforated the Earth's surface with boreholes to deplete a resource that we all, ultimately, hold in common. Now we stand at the threshold of what I call a third stage in our relationship with water; one where, apparently, cataclysm looms on every side. Vivid Doomsday scenarios espoused by numerous writers have Phoenix imploding as its water supplies fail, the Nile drying up, tens of thousands of people crossing national boundaries to find water.

Futurist after futurist warns that water wars are a certainty in coming centuries. Alas, at least some of these cataclysms could descend upon us if we persist in denying the seriousness of the water crisis and deluding ourselves into thinking that uncontrolled growth and more dams are the solution. They are not.

Yes, there will be shortfalls, people will go thirsty and die, but in the end, as has happened so many times in the past, human ingenuity, quite apart from technology, will find solutions. And in the process, we will develop new, much more respectful relationships with water, even if they do not necessarily have the profound spiritual intertwinings of earlier times.

In the short term, there are four potential ways of improving the situation, but none of them will solve the problem of chronic overdrawing. One lies in spending large sums on systematic improvements to storage and delivery, to the infrastructure behind water supplies. Underground reservoirs have potential. So do simple things like replacing leaking pipes, lining earth-bottomed canals and irrigating plants at their roots with just the right amount of water, among many others. A second solution also makes sense: make farming less thirsty, by using drought-resistant, higher-yielding, even genetically-modified crops. This is much easier said than done, for significant technological breakthroughs lie a long way in the future. Also, we should not forget that planting more crops means more use of water, since each plant transpires vapour into the atmosphere through photosynthesis. One possible solution may lie in developing plants that can grow using saline water but, again, this development is in the future. Then there's another seemingly attractive option: desalinisation. Surprisingly, this has been around a long time. Aristotle remarked that "salt water, when it turns to steam, becomes sweet and the steam does not form salt water when it condenses". Julius Caesar's legions drank fresh water condensed from sea water during his siege of Alexandria in 48-47 BCE. As self-appointed visionaries keep reminding us, desalinisation seems like the answer to all our problems but, in spite of improvements in efficiency, there remain significant environmental and technical problems. Desalinisation, which involves creating and recondensing steam, consumes prodigious amounts of energy, even in its most efficient iterations, so it is currently confined to nations where oil is cheap and abundant.

Nearly half the existing desalinisation plants are in the Arabian Peninsula and along the Persian Gulf, especially in Saudi Arabia and the Gulf states. In most other places, the cost of desalinisation is three or four times that of conventional water sources.
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  1. dandare's Avatar
    If the fresh water is becoming more scarce and the sea level is rising shurely the answer is to buil de-salination plants and turn the salt water in to fresh water.
    If we had done this in the African droudt spots years ago the people there would not be suffering now. In fact given the weather in the area they would be able to grow fruit and veg and create a food based export economy. Everyone would have been a winner.
  2. Scooby's Avatar
    Technology is the answer for desalinisation, the process is a steam - condensate system, but the technology when linked to enhanced solar power actually works, the plants require large amounts of energy, but they are usually in geographic areas where solar power works exceptionally well, the problem is investment to start with, famine and drought usually happen in the poorest and most unstable countries where getting one of these systems up and running would virtually impossible.