River And Lakes
The rivers of India can be divided into three groups: the great Himalayan rivers of the north, the westward-flowing rivers of central India, and the eastward-flowing rivers of the Deccan Plateau and the rest of peninsular India. Only small portions of India’s rivers are navigable because of silting and the wide seasonal variation in water flow (due to the monsoon climate). Water transport is thus of little importance in India. Barrages, structures that redirect water flow, have been erected on many of the rivers for irrigation, diverting water into some of the oldest and most extensive canal systems in the world.
The Indian subcontinent’s three great northern rivers, the Indus, the Brahmaputra, and the Ganges, flow through India. The Indus, about 2,900 km (1,800 mi) long, originates in the Himalayas of western Tibet, flows through the Ladakh region of Jammu and KashmÄ«r state, then enters Pakistan. The waters of three of its tributaries, the Sutlej, RÄvi, and ChenÄb, have been diverted, under the Indus Water Treaty, for use in India. The Brahmaputra is about 2,900 km (1,800 mi) long and likewise rises in the Tibetan Himalayas. It flows through Assam state and then south through Bangladesh to the Bay of Bengal. The 2,510-km (1,560-mi) Ganges, known as Ganga in India, rises in the Indian Himalayas and enters the Gangetic Plain northeast of Delhi. At AllahÄbÄd it is joined by its major tributary, the Yamuna. The main branch of the Ganges flows through Bangladesh to the Bay of Bengal, while a second branch meets the bay in India, near Kolkata. Both the Brahmaputra and Ganges rivers discharge enormous amounts of water, almost all of it during the monsoon season.
The Narmada, at 1,289 km (801 mi) long, is India’s major west-flowing river; it flows mainly in the state of Madhya Pradesh, emptying into the Arabian Sea in GujarÄt state. Its annual runoff is less than one-tenth that of the Ganges system. Its basin consists of about 5 million cultivable hectares (about 12 million acres), although only a small percentage is currently irrigated. A major dam system under construction will divert large amounts of water for irrigation, particularly in the state of GujarÄt.
Three major rivers flow east into the Bay of Bengal, rising from the western hills of the Deccan Plateau. The northernmost is the GodÄvari, about 1,400 km (900 mi) long. It has a basin (the area drained by a river) one-third the size of the Ganges, and carries one-tenth of the amount of water the Ganges carries. Emptying into the sea not far south of the GodÄvari is the Krishna (about 1,300 km/800 mi), with a basin equal to the GodÄvari but carrying only two-thirds of the amount of water. The smallest of the three rivers is the KÄveri (760 km/470 mi), with a basin less than one-third the size of the other two rivers.
India has a number of other significant rivers. Tributaries of the Ganges from the north include the Kosi, Gandak, GhÄghara, Gumti, and SÄrda rivers. Joining the Ganges from the south are the Betwa, Chambal, and Son rivers. The Mahi, SÄbarmatÄ«, and TÄpi flow west into the Arabian Sea in GujarÄt. Flowing west to join the Indus River in Pakistan are the BeÄs, ChenÄb, Jhelum, RÄvi, and Sutlej, all rivers of the Punjab (Hindi for “five rivers”) region of India and Pakistan. The MahÄnadÄ« and BrÄhmani rivers rise in Chhattisgarh and Orissa states, respectively, and flow east to empty into the Bay of Bengal. The waters of all these rivers are used to irrigate crops, but the amount stored for purposes of irrigation and power generation varies enormously from river to river depending, among other things, on the number of dams on the river.
There are only a few natural lakes in India of any size. Chilika Lake on the coast of Orissa varies seasonally in volume and is alternately fresh and salty. Other lakes, such as SÄmbhar in RÄjasthÄn state and Colair in Orissa state, typically dry out completely before the monsoon begins. Small artificially created ponds called tanks are a feature of virtually every village, serving as sources of water for drinking, bathing, and irrigation.
