Is the Earth really running out of water? A better way to measure water scarcity

We've all heard the Earth is running out of water... but how is that measured? Is there a better way to gauge water scarcity? Dr. Kate Brauman thinks so. She's lead scientist for the Global Water Initiative at the Institute on the Environment at the U of MN. She talked with Dick about her ideas on more accurate and useful ways to determine water scarcity.