NG Live!: Sandra Postel: Troubled Waters

National Geographic Fellow Sandra Postel views the world through a water lens, advocating for all to make simple and easy changes to their everyday lives that will help "Change the Course" of the Earth's precious supply of freshwater.

The National Geographic Live! series brings thought-provoking presentations by today’s leading explorers, scientists, photographers, and performing artists right to your YouTube feed. Each presentation is filmed in front of a live audience at National Geographic headquarters in Washington, D.C. New clips air every Monday.