Mexico is the world’s top producer of silver. But mining is a water-intensive industry, and water scarcity in Puebla state is expected to grow worse in a changing climate. Indigenous communities there have long-protested against proposed mining projects, fearing the loss of important water sources. This month in southern Mexico, a group of Indigenous activists is organizing a caravan to communities impacted by mining and extractive industries to build strength in numbers. Reporter Michael Fox has the story.