No one can say we were not warned.

AuthorBrooks, David B.
PositionThinking Aloud

Shortages of fresh water are nothing new. Arid and semi-arid regions have always been short of water, and much of the rest of the world suffers periodically when expected rainfall is either inadequate or irregular. What is new is the extent of the problem. Already, one third of the world's population suffers from inadequate access to clean, fresh water. Within a couple of decades, that proportion will double to two thirds.

Two aspects of the old problem are also new. First, no one can say that we were not warned. The world's water problems have been documented in report after report. A recent study from the International Food Policy Research Institute (IFPRI) is probably the best, which emphasizes the difficulty of providing water to grow food that, in the long run, is a greater problem than drinking water. Second, the traditional approach to solve water problems--tapping new sources of supply--is running dry. From Roman times and even before, engineering works have brought water to towns and fields. However, this approach was never cheap and is getting ever more expensive. The cost to deliver another litre of water is doubling every decade or so.

Worse yet, in many areas, notably the Middle East, North Africa, South Asia and Eastern Europe, there are few new sources to tap (on the surface or underground). The cost to desalinate salt water is dropping, but only to the extent that it can be considered for potable uses in the home. It is (and seems likely to remain) way above what farmers can pay. Other supply options, such as cloud seeding, inter-basin pipelines, movements by sea, etc., are technically feasible but not cheap; most have environmental problems and all are politically complex.

Analysis of the dilemma of inadequate fresh water leads to some strong conclusions:

* Both international organizations and national governments must shift emphasis from expanding the water supply to limiting demand.

* Both richer and poorer nations must learn how to get along with less water in total, and much less water per capita.

* Nations that have been water-rich must become water-efficient. Those that have always been water-poor must become even more efficient.

Most current work on water demand focuses on efficiency--getting prices right and finding better technologies. These approaches will pay off; just as we found with energy some thirty years ago, the cheapest new "source of water supply" will be in conservation of water demand.

Experiments demonstrate that in almost every sector, cost-effective savings of 20 to 50 per cent of water use are readily available--sometimes as simple as tightening valves--mostly with only minor changes in technology.

For favoured water-rich...

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