Understanding Drainage and River Systems
What is Drainage?
The term drainage refers to the river system of an area.
- Small streams come together to form a main river.
- The main river eventually flows into a larger water body, like a lake, sea, or ocean.
- The area drained by one river system is called a drainage basin.
- Elevated areas, such as mountains, separate drainage basins.
- These elevated areas are known as water divides.
Drainage Systems in India
India has two major types of drainage systems:
- Himalayan Rivers
- Peninsular Rivers
Himalayan Rivers
- Himalayan rivers are mainly perennial, which means they have water all year round.
- They receive water from rain and melted snow from mountains.
- Key rivers: Indus and Brahmaputra.
- These rivers have long courses from their source to the sea.
Characteristics of Himalayan Rivers
- They cut through mountains and create gorges.
- They perform heavy erosion in their upper courses.
- They carry a large amount of silt and sand.
- In the middle and lower courses, they form:
- Meanders
- Oxbow lakes
- Other depositional features.
- These rivers have well-developed deltas.
Peninsular Rivers
- Many Peninsular rivers are seasonal. This means their flow depends on the rainfall.
- In the dry season, the flow of water can become very low.
- They have shorter and shallower courses compared to Himalayan rivers.
Origin of Peninsular Rivers
- Most Peninsular rivers originate in the Western Ghats and flow towards the Bay of Bengal.
- Some rivers flow towards the west and can you name two of these large rivers?
Summary
- Drainage systems are vital for understanding how water moves in an area.
- In India, we have two main types of rivers: Himalayan and Peninsular.
- Each type has unique features and behaviours based on their geography.
