Ganges Basin

The Ganges basin is a part of the Ganges-Brahmaputra basin draining 1,086,000 square kilometres in Tibet, Nepal, India and Bangladesh. To the north, the Himalaya or lower parallel ranges beyond form the Ganges-Brahmaputra divide. On the west the Ganges Basin borders the Indus basin and then the Aravalli ridge. Southern limits are the Vindhyas and Chota Nagpur Plateau. On the east the Ganges merges with the Brahmaputra through a complex system of common distributaries into the Bay of Bengal. Its catchment lies in the states of Uttar Pradesh (294,364 km²), Madhya Pradesh (198,962 km²), Bihar (143,961 km²), Rajasthan (112,490 km²), West Bengal (71,485 km²), Haryana (34,341 km²), Himachal Pradesh (317 km²) and Delhi (1,484 km²), the whole of Bangladesh, Nepal and Bhutan. Several tributaries rise inside Tibet before flowing south through Nepal. The basin has a population of more than 500 million, making it the most populated river basin in the world.

The basin comprises semi-arid valleys in the rain shadow north of the Himalaya, densely forested mountains south of the highest ranges, the scrubby Shiwalik foothills and the fertile Gangetic Plains. Central highlands south of the Gangetic Plain have plateaus, hills and mountains intersected by valleys and river plains. The important soil types found in the basin are sand, loam, clay and their combinations such as sandy loam, silty clay etc.

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