In spite of all the attention we give to peak oil, peak water may be closer and more serious. Without enough water, there will not be enough food. The issues become more complex when we realize that it takes water to produce energy, and often it takes energy to obtain water.
The latest issue of the IEEE Spectrum is devoted to their special report Water vs. Energy.
As water runs short we have to devote more and more energy to obtaining and treating it. As overused aquifers get deeper, we need more energy to pump it to the surface. More water short areas are turning to energy intensive desalination, such as Australia, which is in a long term drought. The farmers in the Punjab, India's traditional breadbasket, are spending more and more to pump from an aquifer which is declining half a meter a year. China has massive problems from overuse and pollution. The American West is suffering from a long term decline in rainfall, which my really be a return to normal conditions after 150 years of above average rainfall combined with the effects of global warming.
On the other side, making energy requires water. Even something as seemingly innocuous as hydroelectric power loses water from evaporation from the lake behind the dam. Fossil fuel and nuclear power uses water for mining and cooling. Irrigated biofuels are the worst water hog of all.
There are some engineering solution such as increased energy efficiency in desalinization. . One article details Singapore's advanced water re-use system. In the end these only delay the conflict.
If you have no time to read the articles, click through for the excellent graphs, diagrams and maps.
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