A dam in southern Ukraine was split in half, but it is unclear who caused the damage. Thousands are being evacuated as dangerous volumes of water gush downstream.
When the Portuguese electric power grid needs more electricity, a large multinational power company releases millions of gallons of water from a dammed reservoir.
The Bay of Fundy, between Nova Scotia and New Brunswick, has one of the world’s most powerful tides. Now, engineers and scientists hope to finally turn it into a clean energy source.