Ganges

The Ganges (/ˈɡændʒiːz/ GAN-jeez) is a trans-boundary river in Asia that flows through India and Bangladesh. The 2,525-kilometre-long (1,569 mi) river rises in the western Himalayas in the Indian state of Uttarakhand. It flows south and east through the Gangetic plain of North India, receiving the right-bank tributary, the Yamuna, which also rises in the western Indian Himalayas, and several left-bank tributaries from Nepal that account for the bulk of its flow. In West Bengal, India, a feeder canal taking off from its right bank diverts 50% of its flow southwards, artificially connecting it to the Hooghly River. The Ganges continues into Bangladesh, its name changing to the Padma. It is then joined by the Jamuna, the lower stream of the Brahmaputra, and eventually the Meghna, forming the major estuary of the Ganges Delta, and emptying into the Bay of Bengal. The Ganges–Brahmaputra–Meghna system is the second-largest river on earth by discharge.

The main stem of the Ganges begins at the town of Devprayag, at the confluence of the Alaknanda, which is the source stream in hydrology on account of its greater length, and the Bhagirathi, which is considered the source stream in Hindu mythology.

The Ganges is a lifeline to hundreds of millions of people who live in its basin and depend on it for their daily needs. It has been important historically, with many former provincial or imperial capitals such as Pataliputra, Kannauj, Sonargaon, Dhaka, Bikrampur, Kara, Munger, Kashi, Patna, Hajipur, Kanpur, Delhi, Bhagalpur, Murshidabad, Baharampur, Kampilya, and Kolkata located on its banks or those of its tributaries and connected waterways. The river is home to approximately 140 species of fish, 90 species of amphibians, and also reptiles and mammals, including critically endangered species such as the gharial and South Asian river dolphin. The Ganges is the most sacred river to Hindus. It is worshipped as the goddess Ganga in Hinduism.

The Ganges is threatened by severe pollution. This not only poses a danger to humans but also to many species of animals. The levels of fecal coliform bacteria from human waste (feces and urine) in the river near Varanasi are more than 100 times the Indian government's official limit. The Ganga Action Plan, an environmental initiative to clean up the river, has been considered a failure, which is variously attributed to corruption, a lack of will in the government, poor technical expertise, poor environmental planning, and a lack of support from religious authorities.

The upper phase of the river Ganges begins at the confluence of the Bhagirathi and Alaknanda rivers in the town of Devprayag in the Garhwal division of the Indian state of Uttarakhand. The Bhagirathi is considered to be the source in Hindu culture and mythology, although the Alaknanda is longer, and therefore, hydrologically the source stream. The headwaters of the Alakananda are formed by snow melt from peaks such as Nanda Devi, Trisul, and Kamet. The Bhagirathi rises at the foot of Gangotri Glacier at Gomukh, at an elevation of 4,356 m (14,291 ft) and was mythologically referred to as residing in the matted locks of Shiva; symbolically Tapovan, which is a meadow of ethereal beauty at the feet of Mount Shivling, just 5 km (3.1 mi) away.

Although many small streams comprise the headwaters of the Ganges, the six longest and their five confluences are considered sacred. The six headstreams are the Alaknanda, Dhauliganga, Nandakini, Pindar, Mandakini and Bhagirathi. Their confluences, known as the Panch Prayag, are all along the Alaknanda. They are, in downstream order, Vishnuprayag, where the Dhauliganga joins the Alaknanda; Nandprayag, where the Nandakini joins; Karnaprayag, where the Pindar joins; Rudraprayag, where the Mandakini joins; and finally, Devprayag, where the Bhagirathi joins the Alaknanda to form the Ganges.

After flowing for 256.90 km (159.63 mi) through its narrow Himalayan valley, the Ganges emerges from the mountains at Rishikesh, then debouches onto the Gangetic Plain at the pilgrimage town of Haridwar. At Haridwar, a headworks diverts some of its water into the Ganges Canal, which irrigates the Doab region of Uttar Pradesh, whereas the river, whose course has been roughly southwest until this point, now begins to flow southeast through the plains of northern India.

The Ganges river follows a 900 km (560 mi) arching course passing through the cities of Bijnor, Kannauj, Farukhabad, and Kanpur. Along the way it is joined by the Ramganga, which contributes an average annual flow of about 495 m³/s (17,500 cu ft/s) to the river. The Ganges joins the 1,444 km (897 mi) long River Yamuna at the Triveni Sangam at Prayagraj (previously Allahabad), a confluence considered holy in Hinduism. At their confluence the Yamuna is larger than the Ganges contributing about 58.5% of the combined flow, with an average flow of 2,948 m³/s (104,100 cu ft/s).