People tend to fixate on oil as a key natural resource. How much oil is there in the world? Have we passed “peak oil” or is there a lot still to be discovered? (See: “The Blood of Victory.”) They should also give some thought to water. Water was a key natural resource long before oil and it will be a key resource long after oil has ceased to be the chief fuel source. We need it for drinking and for crop irrigation at a minimum.

Of all the water on the earth, 97.5 percent is salt water. Unless one goes through a very costly desalinization process ($2.50-$16/gallon, compared to $0.50-$2.00.gallon for conventional fresh water), this water is not available for use. This leaves 2.5 percent of the world’s water as usable fresh water.

This sounds scary. In theory, there is about 1.5 billion gallons for each person currently living on earth. However, only a small portion of that water is readily available for human use.   The polar ice caps and the glaciers hold about 68 percent of this fresh water. Another 31 percent of it is not readily accessible because it is buried deep underground. Thus, 99 percent of the 2.5 percent is not available for human use (at this time).

Even so, there is a huge amount of fresh water on the earth. Readily available fresh water surface run-off averages 524,151 gallons per person. That sounds reassuring.

The 6.3 billion people now living on earth use about 54 percent of that readily available water. So, it looks like we have a comfortable margin. That is reassuring. It is estimated that world population will rise to 7.8 billion people by 2025 and that use of readily available water will increase to 70 percent of the total. That sounds scary.

That small amount is unevenly distributed, just like most other resources. The UN (God bless its pointy little head) has worked out a scale of measurement for water supply per capita.

“Water abundance”:    >19,000 cubic meters/person. Canada, Russia, the Congo basin, almost all of South America.

“Water surplus”:          3,400-18,999 cubic meters/person. United States, Mexico, France, Ireland, the Balkans, Turkey, Southeast Asia, Kazakhstan.

“Water sufficiency”:   1,700-3,399 cubic meters/person. Most of Europe, Iraq, northern Iran, Afghanistan, most of India, southern and western China, Japan.

“Water stress”:            1,000-1,699 cubic meters/person. Northern Pakistan, South Africa and Zimbabwe, Syria, Czech Republic, Poland.

“Water scarcity”:         < 1,000 cubic meters/person. North Africa, Middle East, Saudi Arabia, southern Iran, southern Pakistan, northern China, southern India.

See: Jen Joynt and Marshall Poe, “The World in Numbers: Waterworld,” Atlantic, July/August 2003, pp. 42-43.

It seems likely that water shortages will start to weigh on both domestic and international politics. The pressure will come from the bottom, from those countries already facing “water stress” and “water scarcity.” One issue will be a campaign for international sharing.   Here the experience of the American West is likely to be useful. Western states have been sharing water resources for decades. It hasn’t always been easy or painless. It’s better than starting from zero.

A second issue will be migration—first internal, then international–by “water refugees.” People will try to ignore this problem for as long as possible. They will describe it as a domestic problem in water-deficient countries. It will not stay contained, any more than climate change.