Ganga River

The Ganga River originates from the Himalayas and flows about 2,525 km eastward and finally drains its water into the Bay of Bengal. The ganga river basin covers around 26.4% of India and supports nearly half of the country’s population. The river originates as Bhagirathi from Gangotri Glacier at Gaumukh at an altitude of 3,892 meter and becomes the Ganga after joining the Alaknanda river at Devprayag in Uttrakhand.

The river flows eastwards through several states like Uttarakhand, Uttar Pradesh, Bihar, Jharkhand, and West Bengal. Before falling into the bay of bengal it forms the world’s largest delta, the Sundarbans, along with the Brahmaputra river. Major tributaries of Ganga include Yamuna, Ghaghara, Gandak, Kosi and Son which significantly contribute to the Ganga river system playing a vital role in irrigation, drinking water, and impact on cultural lives of the people. Despite its significance, the river basin is facing contemporary challenges like flooding, pollution, and heavy siltation, requiring sustainable management for its future.

About Ganga River System

• The Ganga River System is one of the three major river basins that comprise the Himalayan Drainage System.
• The Ganga River and its various tributaries flow through the northern and eastern parts of the Indian subcontinent.
• With a total length of over 2,500 kilometres, the Ganga is the most important river in India and one of the longest in Asia.

Origin and Course of the River System

• The Ganga River is a major river of the Indian subcontinent rising in the Himalayan mountains and flowing about 2,525 km generally eastward through a vast plain to the Bay of Bengal.
• Flowing through a vast length, it crosses five states of India namely:
  • Uttarakhand
  • Uttar Pradesh
  • Bihar
  • Jharkhand
  • West Bengal
• It has a catchment area of 8,61,404 sq. km (26.4%) of India.
• Finally, it drains into the Bay of Bengal. The Ganga River basin is among the most densely populated in the world, housing about half of India’s population.
• The Ganga river supplies over one-third of surface water of India and accounts for more than half of the water usage of the country.
• The Ganga is also revered as one of India’s holy rivers with cultural and spiritual significance extending far beyond the basin.

Course of Ganga River

• The Bhagirathi, considered to be the source stream of the Ganga, emanates from Gangotri Glacier at Gaumukh at an elevation of 3, 892 m (12,770 feet).
• Many small streams comprise the headwaters of the Ganga. The important among these are:
  • Alaknanda
  • Dhauliganga
  • Pindar
  • Mandakini
  • Bhilangana
• At Devprayag, where the Alaknanda meets the Bhagirathi, the river is named Ganga.
• As it flows into the Gangetic Plains at Haridwar, a barrage channels a substantial portion of its water into the Upper Ganga Canal for irrigation purposes.
• Another barrage at Bijnore directs water into the Madhya Ganga Canal, but this occurs only during the monsoon season.
• At Narora, water is further diverted into the Lower Ganga Canal.
• Additionally, the Ramganga River joins the Ganga near Kannauj which contributes the extra water to the river.
• Yamuna confluences Ganga at the Sangam in Prayagraj (Allahabad), making a major contribution to the river flow.
• Beyond Prayagraj, Ganga is joined by several tributaries, most of which are from the north and a few from the south.
• The Farakka barrage in West Bengal regulates the flow of the Ganga River, diverting a portion of its water into a feeder canal that connects to the Hooghly River, helping to keep it relatively free of silt.
• Below the Farakka barrage, the Ganga River divides into two branches:
  • Bhagirathi (Hooghly) is on the right and
  • Padma is on the left.
• The Bhagirathi (Hooghly) River meets the Bay of Bengal approximately 150 km downstream from Kolkata.
• Padma enters Bangladesh and meets rivers Brahmaputra and Meghna before finally joining the Bay of Bengal.

Major Tributaries of Ganga 

The major tributaries of the Ganga River are:

1. Yamuna
2. Ramganga
3. Gomti
4. Ghaghara
5. Gandak
6. Damodar
7. Kosi

Alaknanda River

• The Alaknanda River is one of the primary headstreams of the Ganga River.
  • It originates at the confluence of the Satopanth and Bhagirath glaciers in Uttarakhand.
  • It meets the Bhagirathi River at Devprayag after which it is called as the Ganga River.
• Its main tributaries are the:
  • Nandakini
  • Mandakini
  • Pindar rivers
• The Hindu pilgrimage centre of Badrinath and the natural spring Tapt Kund lie along the banks of the Alaknanda River.
• At its origin, Lake Satopanth is a triangular lake named after the Hindu trinity Lord Brahma, Lord Vishnu, and Lord Shiva.

Bhagirathi River

• The Bhagirathi River is one of the two major headstreams of the Ganga.
  • It converges with the Alaknanda at Devprayag to form the Ganga River.
• It rises at the foot of Gangotri Glacier, at Gaumukh, 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 cuts through granites and crystalline rocks of the central Himalayas.

Dhauliganga River

• The Dhauliganga River originates from Vasundhara Tal, perhaps the largest glacial lake in Uttarakhand.
• The Dhauliganga is a significant tributary of the Alaknanda, alongside the Nandakini, Pindar, Mandakini, and Bhagirathi.
  • It is joined by the Rishiganga River at Raini.
• It merges with the Alaknanda at Vishnuprayag. There it loses its identity and the Alaknanda flows southwest through Nandaprayag, Karnaprayag until it meets the Mandakini River, which comes from the north at Rudraprayag.
• After subsuming the Mandakini, the Alaknanda continues past Srinagar before merging with the Ganga at Devprayag.
• The Alaknanda then fades into the Ganga.