Water, water everywhere - but less 0.5% of Earth's reserves are drinkable.
That's just one shocking fact that Neil deGrasse Tyson and five experts dropped at the 2015 Isaac Asimov Memorial Debate at the American Museum of Natural History.
The event focused on the surprising origins, scarcity, and value of the precious liquid. For World Water Day (March 22), here are a handful of facts that put recent water shortages, like California's recent drought, into stark perspective.