Heat and Harvest: 'Water Banking' in the San Joaquin Valley

The next time you drive down I-5, look east. You see fields and orchards stretching to the Sierra. But what you don't see is California's largest permanent reservoir. That's because it's underground in the rock formations known as "aquifers." For years, farms and cities have pumped water out to meet their needs. But now, as water supplies dwindle, there's a major movement afoot to put some water back.