(Last Updated on : 29/06/2013)
A drainage basin refers to the point of land which absorbs water from rain or snow melt and drains downhill into a river, lake, reservoir, sea or ocean. The drainage basin acts like a funnel, collecting all the water within the area covered by the basin and channeling it into a waterway. India is the land of various water bodies running from north to south and east to west. The extensive Inland Drainage Basin of the country also contributes geographically. Moreover, the drainage basins are historically important too. They help in determining boundaries and enhance trading through water.
The rivers of India are classified as Himalayan, peninsular, coastal, and inland-drainage basin rivers. The Himalayan Rivers are snow fed and the heavy annual average rainfall levels add to the rates of flow. The peninsular rivers are rain-fed, Coastal streams, are found in the western of India and they are short and periodic. However, the rivers of the Inland Drainage Basin flow mostly in western Rajasthan. These river drainage basins are few and they disappear within a year due to scanty rainfall.
Inland Drainage Basin also adds in the hydrology. It can become a logical unit for studying the movement of water within the hydrological cycle. In addition to that the major drainage system of India is beneficial in various ways. As it is a portion of the Earth surface occupied by a main stream, its tributaries are separated from adjacent basins by a drainage divide. Drainage basins are also considered to be important elements in ecology. When water flows over the ground and along rivers it picks up nutrients, sediment, and pollutants. These minerals get transported towards the outlet of the basin, and affect the ecological processes.
The rivers on the Inland Drainage Basin consist of rivers in Western Rajasthan. These rivers are very few in number and they flow for a very short time. The rivers are Sambhar which gets lost in the desert sands, and the Loni drains into the Rann of Kutch. Another major river of the western region is the Mahi River. This river originates from the northern slope of the Vindhya Range in Madhya Pradesh. It enters the southeastern portion of Rajasthan and flows through the Banswara district. Further it takes a 'U' shaped loop in Rajasthan and finally surrenders itself to the sea by a wide estuary near Cambay.