Key words

• Erosion=The action of water wearing away the rocks and soils on the valleys bottom and sides.
• Deposition = The process by which sediment is deposited along the river bed
• Drainage Basin= The area of land drained by a river and its tributary.
• Confluence=A point where two rivers or streams meet.
• Tributary=a smaller stream or river that joins a larger river or stream.
• River source=The starting point of a stream or river.
• River mouth= the point where a river flows into the sea.
• Watershed= the area of high land forming the edge of a river basin.
• Flood plains- the flat area of land on either side of a river in its lower course. During floods, the river overflows its banks and floods the flood plain. Here, the river deposits material.
• Levees- are built to protect against flooding and are built along rivers and canals
• contour lines- lines drawn on a map to show the shape of the land.