Bidyut tells the story about how the river has expanded by a third since he was a child. And the heavy rainfall he has seen lately is more than he has ever experienced before. He lives in the middle of Sundarban, a gigantic river delta that stretches across both sides of the Bangladeshi and Indian border. In recent years, the river has grown a third wider than when Bidyut was a child, and the rains are only getting heavier.