If you live in North America, you've probably never given the cost of water a second thought. In fact, you've probably taken its value for granted probably because it costs very little or because it's vastly abundant. 

In places like Saudi Arabia, however, a liter of water costs five times as much as a liter of gasoline. This is because much of the water in Saudi Arabia is seawater that is purified in desalinization plants (Al Jubail desalination plant shown above). This price relative to fuel is quite different in the United States. For example, a liter of water (from a tap) is virtually free, while a liter of gasoline is around $0.75 (about $3.00 per gallon). 

As a result of this significant difference in cost, it plays a major effect on hu ...