The River Ganga, also known as River Ganges crosses national and international borders of India and Bangladesh during its long extensive flow. Rising in the state of Uttarakhand in the Himalayas, it commences its 2,525 km (1,569 mi) journey eventually reaching the Bay of Bengal, flowing south and east, traversing the Gangetic Plain of North India, moving into Bangladesh, and eventually emptying into the Bay of Bengal.
Being the most sacred river to the Hindus, the Ganga is also a lifeline to millions of Indians who live along its course. Worshipped as the goddess Ganga in Hinduism, the river has been important historically too, with many former imperial capital cities such as Pataliputra, Kannauj, Kashi, Patna, Hajipur, Munger, Bhagalpur, Murshidabad, Baharampur, Kampilya, and Kolkata located on its banks. Even today, the Ganges continues to serve the many that depend on it for their daily needs.
Himalayan rivers are perennial as they are fed by melting snow throughout the year. The Ganges originates at the height of 12,679 ft. As It flows through the Himalayas, it forms deep valleys with steep rock sides caused by the down-cutting of the river. The Ganges causes intense erosional activity upstream and then carries a huge load of sand and silt. Downstream in the plains, it forms large meanders, and consequent depositional features like floodplains, levees, and river cliffs.
- Video: Ganges River From Himalaya To The Bay Of Bengal
- Gomukh: Gangotri Glacier
- Devprayag: Confluence of Alakananda & Bhagirathi
- Allahabad: Confluence of Yamuna, Triveni Sangam
- Doriganj: Confluence with Ghaghra
- Ganges Distributaries and Confluence with Sea
- The Ganges Delta
- Tehri Dam
- Bansagar Dam
- Farakka Barrage
Video: Ganges River From Himalaya To The Bay Of Bengal
Gomukh: Gangotri Glacier
Gangotri Glacier is one of the primary sources of the Ganges. Being approximately 30 km (19 mi) long and 2 to 4 km (1 to 2 mi) wide and having an estimated volume of over 27 cubic km, it is clearly one of the largest glaciers in the Himalayas.
The river starting from this source is called Bhagirathi river and takes the name Ganga or Ganges River after the first confluence point.
Devprayag: Confluence of Alakananda & Bhagirathi
The Alaknanda river starts from Satopanth glacier and joins river Bhagirathi to form the Ganges (Ganga) in Devprayag. The green river is Bhagirathi, which originates from the Gangotri glacier.
The other one is Alakananda, which has a muddy color due to its high sediment content. So technically speaking, Devprayag is the originating point of Ganga.
Allahabad: Confluence of Yamuna, Triveni Sangam
At the confluence of Ganges and Yamuna, the two rivers are visibly different as they merge. The greenish Yamuna is calm and deep, while the clear Ganga is forceful and shallow.
The Allahabad confluence is a place of religious importance in Hinduism and is referred to as Triveni Sangam (confluence of 3 rivers) though the third river – Saraswati – is not visible. Kumbh Mela is a festival organized every 12 years in Allahabad. It is a pilgrimage of faith for Hindus seeking to wash their past sins. It is a mass pilgrimage where Hindu pilgrims bathe in a sacred holy river on platforms erected at this confluence. The most recent Kumbh Mela happened in 2013 over a two month period. An estimated 12 crore (120 million) people visited this Maha Kumbh Mela. The highest daily attendance was over three crore (30 million) on the day of Mauni Amavasya, on 10 February 2013.
Allahabad city has a rich history dating back to 600–700 BC. In 1575 AD, understanding the strategic importance of a place that had immense navigational potential, the Mughal emperor, Akbar the Great, built a magnificent fort on the banks of the holy Triveni Sangam.
Doriganj: Confluence with Ghaghra
Ghaghra river originates near Lake Manasarovar on the Tibetan Plateau. Like other Himalayan rivers, it is a perennial river. It cuts through the Himalayas in Nepal and joins the Sharda river. Together they form a major tributary of the Ganges. By volume, Ghaghara is the largest tributary of the Ganges. By length, it is the second longest tributary of the Ganges, with the Yamuna being the longest tributary.
Ghaghara (also spelled Ghaghra) meets the Ganges at Doriganj in Bihar. At this stage, both the rivers are in their middle course, and so formation of meanders and oxbow lakes are clearly noticeable.
Ganges Distributaries and Confluence with Sea
A common feature in the lower course of a river is the formation of distributaries: channels from the river branch off and flow away from the main channel. The first distributary for river Ganges is the Hooghly river which diverges just before the border with Bangladesh. Hooghly river discharges into the Bay of Bengal at Ganga Sagar.
The main branch/distributary of the Ganges entering Bangladesh is known as the river Padma. The Padma is joined by the distributaries of river Brahmaputra before discharging into the Bay of Bengal through multiple channels. Ganges river most probably had flowed through many channels at different times. The principal channel changes course shifting east & each distributary to the east marks a position of a newer channel than the one to the west of it.
The Ganges Delta
The Ganges joins river Brahmaputra before discharging into the Bay of Bengal through multiple channels creating the Ganges- Brahmaputra delta. The Delta stretches from the Hooghly river in India on the west to the Meghna river in Bangladesh on the east. It is approximately 354 kilometers (220 miles) wide at the Bay of Bengal.
The Ganges Delta has the third highest discharge in the world and sediments and patterns can be seen from space.
It is the world’s largest delta, and also one of the most fertile regions in the world, thus earning the nickname The Green Delta. It is also the most populous river basin in the world despite risks from floods caused by monsoons, heavy runoff from the melting snows of the Himalayas, and North Indian Ocean tropical cyclones. A large part of the nation of Bangladesh lies in the Ganges Delta, and many of the country’s people depend on the delta for survival. Agriculture and Fishing are the major contributors to economy in delta regions. Major crops that are grown in the Ganges Delta are jute, tea, and rice.
The Ganges Delta lies mostly in the tropical wet climate zone, and receives between 1,500 to 3,000 mm (59 to 118 in) of rainfall each year. 75 percent of the region is located less than 10 meters above the sea elevation. This creates freshwater swamp as well as saline or brackish water swamps at the seaward fringe of the delta.
The Sundarbans (Bengali: সুন্দরবন, Shundôrbôn) is a natural region in southern part of the vast river delta on the Bay of Bengal. It is the largest single block of tidal halophytic mangrove forest in the world. The Sundarbans covers approximately 10,000 square kilometers. This region is densely covered by mangrove forests, and is the largest reserve for the Bengal tigers.
The Tehri Dam across the Ganges is the highest dam in India. It is also one of the highest dams in the world. At this point, the river is in its upper course with an elevation of 1,750 m (5,740 ft). In the upper course, the gradient is steep, and the river channel is narrow with V-shaped valleys. Dams constructed in upper course are typically tall & narrow to create reservoirs & these dams can generate electricity because of the steep gradient.
Dam Height – 260.5 m (855 ft)
Dam Length – 575 m (1,886 ft)
The dam creates a reservoir of 4.0 cubic kilometers & generates 1,000 MW hydroelectricity. The reservoir of the dam drowned the District headquarters of Tehri, which have now been shifted to New Tehri.
Bansagar dam is a dam on Sone River, a tributary of Ganges. It is situated in the Ganges Basin. It is a multipurpose dam that provides both irrigation and hydroelectric power generation. Located in the middle course of the river the gradient is more gentle and lateral as sideways erosion has widened the channel. Dams that are constructed in the middle course are shorter and wider compared to the upper course dams.
Dam height : 67 meters
Dam length : 1020 meters
A barrage is built for diverting water whereas a dam is built for storing water in a reservoir. Dams raise the level of water considerably. A barrage is usually built where the surface is flat across meandering rivers. It raises the water level only by a few feet. In the case of barrages, there is very little room for storage, and the canals take water directly from the rivers.
Farakka Barrage is a barrage across the Ganges river located in the lower course of the river. The river channel is wide, and the terrain is flat. The elevation of the river at this point is only 32m. The construction of the Farakka Barrage enables diversion of water to sixty small canals for drinking purposes.
Farakka Barrage Length: 2,240 metres (7,350 ft)