Probing Question: Are water wars in our future?

Schoolkids know that over 70 percent of Earth's surface is washed in water. Yet very little of that abundance — less than two percent — is available for drinking and agriculture. Over the last 50 years, moreover, freshwater use has tripled as global population has doubled, leading to scarcities in many regions of the globe. According to the United Nations, over 1.1 billion of the world's people lack access to a clean water supply.