The Life of Rivers and Lakes: Water's Journey from Source to Sea
Rivers have shaped the landscape for thousands of years. See the journey water takes from a mountain spring all the way to the sea.
Upper course: fast and wild
In the mountains, water flows down a steep bed, carrying stones and forming rapids and waterfalls. The flow is narrow, fast and rich in oxygen.
Middle course: the river widens
As the river descends into the lowlands, its bed widens and slows down. Meanders form, and fine sediments settle around the river.
Lower course and estuary
Before reaching the sea, the river often splits into branches and forms a delta rich in wetlands and waterfowl.
This whole journey can span hundreds of kilometres – and every stretch is home to different plants and animals.