Rivers and Bridges. Rivers | Earth processes | OneGeology Kids | eXtra | OneGeology. All of the earth's rivers contain only about 0.0001% of the earth's water . That doesn't sound like very much, but rivers can do some amazing things. The water in rivers comes from many different sources. Rivers can begin in lakes or as springs that bubble up from underground. Other rivers start as rain or melting snow and ice high up in the mountains. Most rivers flow quickly in the steeply sloping sections near their source. Fast moving water washes away gravel, sand and mud leaving a rocky bottom. Rivers flowing over gently sloping ground begin to curve back and forth across the landscape. Over time rivers can cut through bedrock. When a river reaches a lake or the sea the water slows down and loses the power to carry sediment . Map Data Imagery ©2017 TerraMetrics Some deltas are so large that people can live on them. If you look at a map of rivers and streams you can see they make different kinds of patterns called drainage patterns.
Toggle geology. Static map. Static map. . Geography Essentials - Investigating rivers. Other small streams and rivers, called tributaries, flow into the river and it increases in size as it travels along. The river eventually slows down, curving around to make large bends called meanders. The river ends its journey when it flows into the sea, or a large lake. Some rivers are frozen for part of their journey. These are called glaciers. Cities, towns and villages have grown up on or near rivers because people use the water for many purposes. People need water to drink and to grow food. They use rivers for transporting people and goods. Some rivers are dammed to form reservoirs for drinking water, or to make electricity called hydro-electric power.
Water is constantly flowing from rivers towards the sea. Investigating rivers websites.