• Ganga river system spans across India, Tibet (China), Nepal, and Bangladesh.
• It’s the largest river basin in India and covers about one-fourth of the country’s total area.
• The river system passes through several Indian states and the Union Territory of Delhi, including Uttar Pradesh, Madhya Pradesh, Rajasthan, Bihar, West Bengal, Uttarakhand, Jharkhand, Haryana, Chhattisgarh, and Himachal Pradesh.

Ganga River System

• The Ganga river is formed from six headstreams and five confluences.
• The Alaknanda River meets the Dhauliganga River at Vishnuprayag, the Nandakini River at Nandprayag, and the Pindar River to form the Ganga main stream.
• The Bhagirathi River, considered the source stream, rises at the foot of Gangotri Glacier and flows into the Bay of Bengal, fanning out into the 350km wide Ganga delta.
• The river is called Ganga from Devapryag onwards and joins the Yamuna at Allahabad.
• It turns to the southeast near Rajmahal Hills and bifurcates into Bhagirathi-Hugli in West Bengal and Padma-Meghna in Bangladesh after Farraka.
• Brahmaputra, also known as Jamuna, joins Padma-Meghna at its mouth.
• The Ganga river is 2,525 km long from its source to its mouth along the Hugli.
• Important towns along the river include Haridwar, Kanpur, Soron, Kannauj, Allahabad, Varanasi, Patna, Ghazipur, Bhagalpur, Mirzapur, Ballia, Buxar, Saidpur, and Chunar.
• The Ganga river is considered holy by Hindus and worshipped as the goddess Ganga in Hinduism.

The Five Prayags

1. Devaprayag, the place of confluence of Bhagirathi river and Alaknanda river.
2. Rudraprayag, the place of confluence of Mandakini river and Alaknanda river.
3. Nandaprayag, the place of confluence of Nandakini river and Alaknanda river.
4. Karnaprayag, the place of confluence of Pindar river and Alaknanda river.
5. Vishnuprayag, the place of confluence of Dhauliganga river and Alaknanda river.

Alaknanda

• The Alaknanda River is one of the headstreams of the Ganga river.
• It rises at the confluence and feet of the Satopanth and Bhagirath glaciers in Uttarkhand.
• It meets the Bhagirathi River at Devprayag after which it is called as the Ganga.
• The Alaknanda river’s main tributaries are the Mandakini, Nandakini, and Pindar rivers.
• The Alaknanda system drains parts of Chamoli, Tehri, and Pauri districts in Uttarkhand.
• The Hindu pilgrimage center of Badrinath and the natural spring Tapt Kund are located along the banks of the Alaknanda River.
• Lake Satopanth, which is a triangular lake named after the Hindu trinity Lord Brahma, Lord Vishnu, and Lord Shiva, is located at the origin of the Alaknanda River at a height of 4402m.

Bhagirathi

• The Bhagirathi River is one of the two most important headstreams of the Ganga river and meets the Alaknanda at Devprayag to form the Ganga.
• It rises at the foot of Gangotri Glacier, at Gaumukh, at an elevation of 3892m at the base of Chaukhamba peak in the Uttarkashi district of Uttarakhand.
• The upper catchment of the river is glaciated.
• It cuts spectacular gorges in its middle course where it has cut through granites and crystalline rocks of the central Himalayan axis.
• Gangotri, Uttarkashi, and Tehri are important settlements along the Bhagirathi River.

Dhauliganga

• Vasudhara Tal is the origin of the Dhauliganga river, which is perhaps the largest glacial lake in Uttarakhand.
• Dhauliganga is one of the important tributaries of the Alaknanda river, the other being the Nandakini, Pindar, Mandakini, and Bhagirathi.
• The Rishiganga river joins the Dhauliganga at Raini.
• The Dhauliganga merges with the Alaknanda at Vishnuprayag, after which it loses its identity and flows southwest through Chamoli, Maithana, Nandaprayag, and Karnaprayag until it meets the Mandakini river at Rudraprayag.
• The Alaknanda carries on past Srinagar before joining the Ganga at Devprayag, after which the Alaknanda disappears and the Ganga flows south and then west through important pilgrimage centers such as Rishikesh before descending into the Indo-Gangetic plains at Haridwar.
• The Tapovan Vishnugad Hydropower Project is being constructed on the Dhauliganga.

Rishiganga River

• It is a river in the Chamoli district, Uttarakhand.
• It springs from the Uttari Nanda Devi Glacier on the Nanda Devi Mountain.
• It is also fed from the Dakshini Nanda Devi Glacier.
• It flows through the Nanda Devi National Park and merges into the Dhauliganga River near the village Raini.

Major Tributaries of the Ganga River

Note: In this article, We will read mainly Left Bank Tributaries of The Ganga River. In the next article, we will read about Right Bank Tributaries (i.e Yamuna River System).

Ramganga

• It originates in the southern slopes of Dudhatoli Hill in the Chamoli district of Uttarakhand
• It drains the south-western Kumaun region
• It is fed by underground water reservoirs that create springs
• The lower Himalayan hills of Almora district have many geomorphic features such as incised meanders, paired and unpaired terraces, interlocking spurs, waterfalls, rock benches, cliffs, and towering ridges found in the tract of Ramganga River
• It flows through the dun valley of Corbett National Park
• A dam has been built across the Ramganga at Kalagarh
• Bareilly city is situated on its banks
• Ramganga River meets the Ganga river near Kannauj.
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Gomti

• Gomti river originates from Gomat Taal (Fulhaar jheel) near Madho Tanda, Pilibhit in UP
• It flows for 900km through UP and meets the Ganges River in Ghazipur
• Markandey Mahadeo temple is situated at the Sangam of Gomti and Ganga
• Sai River is the most important tributary, which joins Gomti near Jaunpur
• The cities of Lucknow, Lakhimpur Kheri, Sultanpur, and Jaunpur are located on the banks of Gomti
• Gomti river cuts the Jaunpur city into equal halves and becomes wider in Jaunpur.

Ghaghra

• The Ghaghara is a perennial river.
• It originates from the glaciers of Mapchachungo.
• It is alternatively known as Karnali or Kauriala.
• The river originates from the Tibetan plateau near Lake Mansarovar.
• It cuts through the Himalayas in Nepal.
• The Sharda River joins it at Brahmaghat in India.
• It is a major left-bank tributary of the Ganga.
• It joins the Ganga at Chhapra in Bihar.
• The total length of the river is 1080km.
• This river is the main source of water in Bara-Banki District of UP.
• Rapti, Chhoti Gandak, Sharda, and Sarju are the major tributaries of this river.
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Sharda

• The Sarda river rises in the Milam glacier in the Nepal Himalayas, where it is known as the Goriganga.
• The Sharda river originates from the Greater Himalayas at Kalapaani in the Pithoragarh District of Uttarakhand at an altitude of 3600m.
• Kalapaani is located on the route of Kailash Manasarovar Yatra tour.
• In Nepal, the river is named as River Mahakali, after the Goddess Kali whose temple is situated in Kalapaani near the Lipu-Lekh pass at the border between India and Tibet.
• The river forms the border between the Nepalese Mahakali Zone and Uttarkhand.
• The river flows in a gorge section in the upper region.
• After descending into the plains in India, the river is known as Sarda, which eventually meets the Ghaghara river.

Sarayu

• The Sarayu river is also known as Sarju
• It flows through the state of Uttar Pradesh in India
• It originates from a ridge located south of the Nanda Kot mountain in the Bageshwar district of Uttarakhand
• The river is considered of great historical and religious significance and is mentioned in ancient texts such as the Vedas and Ramayana
• It is a left-bank tributary of the Ghaghara River
• Every year on Ram Navami, the festival that celebrates the birth of Lord Ram, thousands of people take a dip in the sacred Sarayu river in Ayodhya.

Rapti

• The Rapti river originates south of a ridgeline between the western Dhaulagiri Himalaya and the Mahabharat Range in Nepal.
• Its mainstream starts as a spring on the southern slopes of the Lower Himalayas and is fed by underground water.
• The river is prone to recurrent floods and is sometimes called “Gorakhpur’s Sorrow.”
• The Rapti has several major left-bank tributaries including Lungri Khola, Jhimruk Khola, Ami River, and Rohini River, as well as a right-bank tributary called Arun Khola.

Gandak

• The river is formed by the Kali and Trisuli rivers in Nepal.
• From this point to the Indian border, it is called the Narayani.
• It enters the Ganga river at Sonepur after flowing for 765 km.
• The Burhi Gandak runs parallel to and east of the Gandak River.
• The upper catchment area of the river is bleak and desolate.
• The middle and lower courses of the river flow through V-shaped valleys with incised meanders and paired and unpaired terraces.

Burhi Gandak

• The river is 320 km long and originates from Chautarva Chaur near Bisambharpur in West Champaran district of Bihar.
• It initially flows through East Champaran district.
• After flowing for about 56 km, the river takes a southerly turn where two rivers – Dubhara and Tour – join it.
• Thereafter, the river flows in a south-easterly direction through Muzaffarpur district for about 32 km.
• It flows parallel to and east of the Gandak River in an old channel.
• The main tributaries of the Burhi Gandak are Masan, Balor, Pandai, Sikta, Tilawe, Tiur, Dhanauti, Kohra, and Danda.
• Samastipur is situated on the Burhi Gandak river.
• There are no major or medium projects over the Burhi Gandak river system.
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Kosi

• The Kosi river, also known as Saptakoshi for its seven Himalayan tributaries, is an antecedent transboundary river that flows through Nepal and India.
• Some of the rivers in the Kosi system, such as the Arun, Sun Kosi, and Bhote Koshi, originate in Tibet.
• The Kosi river is 729 km long and is one of the largest tributaries of the Ganga. It joins the Ganga at Kursela in Kathiar district.
• The Kosi catchment area includes the highest peak in the world, Mt. Everest, and the Kanchenjunga.
• Bagmati is an important tributary of the Kosi river.
• Over the last 250 years, the Kosi river has shifted its course over 120 km from east to west.
• The river’s unstable nature has been attributed to the heavy silt it carries during the monsoon season, which has led to it being called “The Sorrow of Bihar.”

Son

• The Son river is 784 km long and originates near Amarkantak in Madhya Pradesh, just east of the headwater of the Narmada River.
• It flows north-northwest through Madhya Pradesh before turning sharply eastward when it encounters the southwest-northeast running Kaimur Range.
• The Son river parallels the Kaimur hills, flowing east-northeast through Uttar Pradesh, Jharkhand, and Bihar states, and joins the Ganga just above Patna.
• Geologically, the lower valley of the Son river is an extension of the Narmada Valley, and the Kaimur Range is an extension of the Vindhya Range.
• Dehri is a major town situated on the Son river.
• The chief tributaries of the Son river are the Rihand and the North Koel on the right bank, and the Ghaggar, Johila, and Chhoti Mahanadi on the left bank.
• The Son river is largely forested and sparsely populated.
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Rihand

• The Rihand river rises from the Matiranga Hills in the region southwest of the Mainpat plateau, which is about 1000m in Chhattisgarh.
• The Rihand and its tributaries form a fertile plain in the central part of the district stretching from around Ambikapur to Lakhanpur and Pratappur.
• It then flows north into Sonbhadra district of Uttar Pradesh, where it joins the Son river.
• The principal tributaries of the Rihand river are the Mahan, the Morana (Morni), the Geur, the Gagar, the Gobri, the Piparkachar, the Ramdia, and the Galphulla.
• The Rihand Dam was constructed across the Rihand river near Pipri in Sonbadra district of Mirzapur division in 1962 for hydropower generation, and the reservoir impounded behind the dam is called Govind Ballabh Pant Sagar.

North Koel

• This 260km long river rises on the Ranchi plateau and enters Palamau division below Netarhat near Rud
• After flowing nearly due west for about 30km, it turns north at an almost complete right angle through a gorge at Kutku and flows through the centre of the district till it falls into the Son a few miles northwest of Haidamagar
• The North Koel, along with its tributaries, meanders through the northern part of Betla National Park
• The principal tributaries are the Auranga, the Amanat, and the Burha.
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Namami Gange Yojana

• The Namami Gange Project is a Union Government project aimed at cleaning and protecting the Ganga river comprehensively.
• The project has a budget of Rs. 2037 Crore and consists of nearly 288 projects, with a total corpus of Rs. 20,000 crore.
• It is operated by the Department of Water Resources, River Development, and Ganga Rejuvenation, Ministry of Jal Shakti.
• The project covers 8 states, 47 towns, and 12 rivers and aims to make over 1,632-gram panchayats open defecation-free by 2022.
• The project involves several ministries, including Environment, Urban Development, Shipping, Tourism & Rural Development Ministries.
• The National Mission for Clean Ganga (NMCG) and State Program Management Groups (SPMGs) are implementing the program.
• The project includes setting up River Regulatory Zones, developing rational agricultural practices & efficient irrigation methods, and setting up a Ganga Knowledge Centre.
• Pollution will be checked through various methods, including bio-remediation, in-situ treatment, and municipal sewage & effluent treatment plants.
• The project also introduces immediate measures to arrest the inflow of sewage and a PPP approach for pollution control.
• The project will introduce a 4-battalion Territorial Army Ganga Eco-Task Force.

Other Initiatives Taken

• Ganga Action Plan: Implemented in 1985 to improve water quality by treating sewage.
• National River Conservation Plan: Extension of Ganga Action Plan phase-2 to clean Ganga river.
• National River Ganga Basin Authority (NRGBA): Formed in 2009, declared Ganga as ‘National River’.
• Clean Ganga Fund: Formed in 2014 for cleaning up Ganga, setting up waste treatment plants, and conserving biotic diversity.
• Bhuvan-Ganga Web App: Involves public in monitoring Ganga pollution.
• Ban on Waste Disposal: In 2017, the National Green Tribunal banned waste disposal in Ganga.