Drainage System in India:
i. Indian river systems are grouped into two main classes. They are:
- The Himalayan rivers and
- The Peninsular Rivers.
ii. Himalayan rivers originate from the Himalayan Mountains and the Peninsular rivers from the Plateau. Hence the Himalayan and the Peninsular Rivers are different from each other.
a. The Himalayan rivers are mostly perennial.
b. They have water throughout the year1 because they get water from rain and also from melted snow from the lofty mountains.
i. The two major Himalayan Rivers are the Indus and the Brahmaputra.
ii. They originate from the north of the mountain ranges.
iii. They have cut through the mountains making spectacular gorges, due to upliftment of the mountains and down cutting of rivers simultaneously.
iv. The courses of the Himalayan Rivers are very long from their source to the sea.
v. They are known for their intensive erosional activity in their upper courses.
vi. They carry huge loads of silt and sand.
vii. In the middle and lower courses, these rivers form braided streams and meanders and many other depositional features in their flood plains.
c. They have formed well-developed deltas.
iii. Peninsular rivers are seasonal, because their flow is dependent on rainfall.
a. During the dry season, even the large rivers have a highly reduced flow of water in their channels.
b. These rivers have shorter and shallower courses as compared to their Himalayan counterparts.
c. Some of them originate in the Eastern Ghats and flow towards the west. But most of the rivers originate in the Western Ghats and flow towards the Bay of Bengal.