The Himalayan River system comprises rivers like the Indus, Ganga, and Brahmaputra, sustained by a combination of melting snow and precipitation, rendering them perennial.These major Himalayan rivers, characterized by their length, boast numerous tributaries. A river system, consisting of the main river and its tributaries, undergoes transformations upon entering the plains, giving rise to depositional features like expansive valleys, oxbow lakes, flood plains, intricately braided channels, and deltas near the river's outlet.

• The evolution of the Himalayan drainage system traces back to the Miocene period, approximately a few million years ago. 
• At that time, a colossal river known as the Shiwalik or Indo-Brahma extended across the entire longitudinal expanse of the Himalayas, stretching from Assam to Punjab and onward to Sind. 
• Ultimately, it was discharged into the Gulf of Sind in lower Punjab.
• The stability and lacustrine origin of the Shiwalik, evidenced by its diverse alluvial deposits, including sands, silt, clay, boulders, and conglomerates, validate this historical perspective. Following this era, the Himalayan rivers underwent a significant dissection, leading to the formation of three primary drainage systems.
• This fragmentation is believed to have occurred during the Pleistocene period, marked by instability in the western Himalayas, particularly associated with the elevation of the Potwar Plateau (Delhi Ridge). 
• This elevated terrain acted as a hydrological barrier, influencing the separation of the Indus and Ganga drainage systems.
• Furthermore, a similar Pleistocene event involved the down-thrusting of the Malda gap region between the Rajmahal hills and the Meghalaya plateau. 
• This geological phenomenon redirected the courses of the Ganga and Brahmaputra systems, compelling them to flow towards the Bay of Bengal. 
• These intricate geological processes played a crucial role in shaping the contemporary configuration of the Himalayan drainage system.

INDUS RIVER SYSTEM

• The Indus River system stands as one of the world's major river basins, with the Indus River, also known as Sindhu, being the westernmost Himalayan river in India. 
• Originating from a glacier at Bokhar Chu in the Kailash Mountain range in Tibet, it is referred to as 'Singi Khamban' in Tibet, signifying Lion's Mouth. 
• The river flows northwest, coursing between the Ladakh and Zanskar mountain ranges before traversing Ladakh and Baltistan.
• As it cuts through the Ladakh range, it forms a spectacular gorge near Gilgit in Jammu & Kashmir. 
• Entering the Dardistan region of Pakistan around Chillar, the river is joined by numerous Himalayan tributaries, including the Shyok, Gilgit, Zaskar, Hunza, Nubra, Shigar, Gasting, and Dras.
• The Indus eventually emerges from the highlands around Attock, where it receives the Kabul River on its right bank. 
• Progressing southward, it accepts the 'Panjnad' just above Mithankot. 
• The Panjnad refers to the confluence of the five rivers of Punjab, namely Satluj, Beas, Ravi, Chenab, and Jhelum.

Ultimately, the Indus River empties into the Arabian Sea to the east of Karachi. In India, the Indus exclusively flows through the Leh district of Jammu and Kashmir.

INDUS- TRIBUTARIES

• The Indus River is enriched by a diverse array of Himalayan tributaries, with notable names such as the Shyok, Gilgit, Zaskar, Hunza, Nubra, Shigar, Gasting, and Dras contributing to its flow.
• Emerging from the highlands at Attock, the river encounters the Kabul River on its right bank.
• In addition to the above, the Khurram, Tochi, Gomal, Viboa, and Sangar stand as significant tributaries joining the right bank of the Indus, all tracing their origins to the Sulaiman ranges.
• On the left bank, the Indus is joined by several prominent tributaries, including the Zanskar River, Suru River, Kishanganga (Neelam) River, Jhelum River, Chenab River, Ravi River, Beas River, Satluj River, and Panjnad River.
• Each of these rivers contributes to the overall flow and dynamics of the Indus River system.

Satluj River:

• Source: The source of the Satluj River is the "Rakas tal" near Mansarovar in Tibet. In Tibet, it is initially known as the Langechen Khambab.
• Course: The river flows approximately parallel to the Indus River for about 400 kilometres before entering India. It crosses the Himalayan peaks at Shipki La and enters the Punjab plains.
• Confluence: The Satluj River merges with the Beas River near Hari-ke-Patan, Amritsar, Punjab. The united river then enters Pakistan after the confluence.
• Bhakra Nangal Project: The river contributes to the Bhakra Nangal project's canal system.

Beas River:

• Source: Beas Kund, near Rohtang Pass in Himachal Pradesh, marks the origin of the Beas River.
• Course: It runs through the Kullu valley in Himachal Pradesh, forming gorges in the Dhauladhar mountain at Kati and Largi. The river then flows into the Punjab plains, where it meets the Satluj at Harike, Punjab.
• Pan-Indian Flow: The Beas River traverses across India, contributing to the northern river systems.

Ravi River:

• Source: The Killu Hills, west of Rohtang Pass in Himachal Pradesh, is the starting point of the Ravi River.
• Course: The river flows across the Chamba valley in Himachal Pradesh, draining the region between the Pir Panjal and Dhauladhar hills in the southeast. It enters the Punjab plains, running along the Indo-Pakistan border, and eventually enters Pakistan, merging into the Chenab River at Sarai Sidhu.

Chenab River:

• Source: The Baralacha Pass in Himachal Pradesh is the starting point of the Chenab River. It is formed by the confluence of two streams, the Chandra and the Bhaga, near Keylong in Himachal Pradesh. It is sometimes referred to as Chandrabhaga.
• Length: The Chenab is the largest tributary of the Indus, flowing for over 1180 kilometres before entering Pakistan.

Jhelum River:

• Source: The Jhelum River originates from a spring at Verinag, in the southeastern region of the Kashmir valley, on the slopes of the Pir Panjal.
• Course: It runs past Srinagar, reaches Wular Lake, and then enters Pakistan through a steep, narrow valley. The river connects with the Chenab at Jhang, Pakistan.

GANGA RIVER SYSTEM

The Ganga River:

• Source: The Ganga, India's most significant river, originates near Gaumukh in Uttarakhand's Uttarkashi district, flowing from the Gangotri glacier. In this region, it is named Bhagirathi.
• Confluence: The Bhagirathi meets the Alaknanda at Devprayag, transforming into the Ganga River.
• Plains Entry: Upon reaching Haridwar, the Ganga enters the plains, taking a southward, then south-eastward, and finally eastward course.
• Distributaries: Near the Bay of Bengal, the Ganga separates into two distributaries, the Bhagirathi and the Hugli.
• River System: The Ganga river system is the largest in India, featuring a network of perennial and non-perennial rivers originating from both the Himalayas in the north and the Peninsula in the south.
• Tributaries: The Son is the main right bank tributary, while prominent left bank tributaries include the Ramganga, Gomati, Ghaghara, Gandak, Kosi, and Mahananda.
• Bay of Bengal: The Ganga ultimately empties into the Bay of Bengal at Sagar Island.

Cultural Significance:

• The Ganga holds immense cultural significance in India, playing a central role in religious practices, rituals, and traditions.
• Pilgrims from across the country visit its banks for spiritual purposes and to partake in religious ceremonies.
• The river is considered sacred in Hinduism, and its waters are believed to have purifying properties.
• Several major cities and towns along the Ganga, such as Varanasi, Haridwar, and Prayagraj, are important cultural and religious centers.

Ecological Importance:

• The Ganga River basin supports diverse flora and fauna, including several endangered species.
• The river plays a crucial role in sustaining agriculture and fisheries along its course.
• Efforts for Ganga rejuvenation and conservation are ongoing to address pollution and ensure the ecological health of the river.

Important Tributaries of Ganga - Right Bank

Yamuna

• Source: Originates on the western slopes of the Bandarpunch range in the Yamunotri Glacier (Uttarakhand).
• Confluence: Merges with the Ganga in Prayag (Allahabad).
• Major Tributaries: Tons, Chambal, Sindh, Betwa, and Ken, originating from Aravallis, Vindhya Range, and Malwa Plateau.

Tamas

• Source: Tamakund in the Kaimur Range (Madhya Pradesh).
• Confluence: Meets Ganga in Sirsa (Uttar Pradesh).

Son

• Source: Begins on Amarkantak Hill in Madhya Pradesh near the Narmada River.
• Confluence: Flows into the Ganga near Patna in Bihar.

Punpun

• Origin: Indigenous to the Chotanagpur Plateau region of Jharkhand's Palamu district.
• Confluence: Merges with the Ganga near Fatwa (Patna).

Left Bank

Ramganga

• Origin: Gets its name from the Garhwal hills near Gairsain (Uttarakhand).
• Course: Flows south-west after passing the Shiwaliks, reaches Uttar Pradesh plains at Najibabad, and joins the Ganga at Kannauj.

Gomti

• Source: Flows from Gomat Taal (Fulhaar Jheel) near Pilibhit (Uttar Pradesh).
• Confluence: Joins the Ganga at Kaithi, Ghazipur (Uttar Pradesh).

Ghaghara

• Origin: Year-round transboundary river originating in the Mapchachungo glaciers near Mansarovar Lake in Tibet.
• Confluence: Joins the Ganga at Chhapra, Bihar.
• Note: Also known as Karnali in Nepal, the longest river in the country.

Gandak

• Source: Nhubine Himal Glacier in Mustang area of Nepal's border.
• Confluence: Joins the Ganga at Patna, Bihar.
• Note: Also known as Kali Gandaki and Narayani in Nepal.

Kosi

• Origin: Arun, its major stream, rises on the northern slopes of Mt. Everest in Tibet.
• Confluence: Joins the Ganga at Kursela in Katihar district (Bihar).
• Note: Known as "Bihar Sorrow."

Mahananda

• Origin: Darjeeling highlands in West Bengal.
• Confluence: Joins the Ganga at Godagari Ghat, Bangladesh.
• Note: Ganga's most eastern tributary.

BRAHMAPUTRA RIVER SYSTEM 

Brahmaputra River: Key Features

Origin:

• Location: Chemayungdung glacier near Mansarovar Lake in the Kailash range.
• Name: Known as Tsangpo in southern Tibet, translating to "purifier."
• Tributary: Rango Tsangpo is the main right-bank tributary in Tibet.

Course in India:

• Emergence: After carving a deep valley in the Central Himalayas at Namcha Barwa.
• Name Change: Becomes Siang or Dihang upon entering India west of Sadiya in Arunachal Pradesh.
• Tributaries: Receives left bank tributaries Dibang or Sikang and Lohit, transforming into the Brahmaputra.

Flow in Bangladesh:

• Confluence: Joins the Padma River in Bangladesh.
• Outlet: Empties into the Bay of Bengal.

Significance:

• Magnitude: One of the world's greatest rivers.
• Topography: Carves a deep valley and emerges as a powerful torrent in the Central Himalayas.
• Name Meaning: "Tsangpo" signifies purification in Tibetan.
  • The Brahmaputra's course and characteristics undergo significant changes as it traverses Tibet, India, and Bangladesh.
  • Left bank tributaries, including the Dibang and Lohit, contribute to the river's flow and character.
  • In Bangladesh, the Brahmaputra and the Padma join, eventually draining into the Bay of Bengal.

Important Tributaries of Brahmaputra: Key Features

Left Bank Tributaries:

Burhi Dihing:

• Significance: Major left bank tributary of the Brahmaputra.
• Location: Flows on the left side of the Brahmaputra.

Dhansari (South):

• Significance: Key left bank tributary.
• Location: Flows on the left side of the Brahmaputra.

Right Bank Tributaries:

Subansiri:

• Nature: An antecedent river originating in Tibet.
• Location: Joins Brahmaputra on its right bank.

Kameng:

• Significance: Important right bank tributary.
• Location: Contributes to the Brahmaputra's flow from the right side.

Manas:

• Significance: Vital right bank tributary of the Brahmaputra.
• Location: Joins the Brahmaputra from the right.

Sankosh:

• Significance: Important right bank tributary.
• Location: Contributes to the Brahmaputra's flow from the right side.
  
  Course in Bangladesh:
• Entry into Bangladesh: Near Dhubri, the Brahmaputra enters Bangladesh.
• Confluence: Tista river joins on its right bank in Bangladesh, where it is known as the Yamuna.
• Joining Padma River: Eventually joins the Padma River in Bangladesh.
• Outlet: Empties into the Bay of Bengal.

Hydrological Characteristics:

• Floods and Channel Shifting: Common occurrences.
• Bank Erosion: A notable feature.
• Sediment Load: High due to substantial rainfall in the catchment region.

Note:

• The Brahmaputra's hydrological dynamics are influenced by its significant tributaries, which contribute to its flow and sediment transport.
• The river undergoes changes in behavior and morphology, leading to challenges such as floods, channel shifts, and bank erosion.

Significance of Himalayan Drainage: Key Aspects

Geological and Structural Significance:

• The major Himalayan rivers traverse steep gorges, often indicating geological structural restrictions such as fault lines.
• They originate north of the mountain ranges, contributing to the unique topography of the region.

Direction of River Flow:

• Rivers of the Indus system generally flow northwesterly.
• Indus-Ganges-Brahmaputra systems' rivers, on average, flow easterly across the Himalayan area.
• This directional flow is influenced by the region's geology and structural features.

Vital for North India:

• The Himalayan river system is crucial for North India, providing both surface and groundwater.
• It serves as a primary source for irrigation, supporting agriculture, a cornerstone of the region's economy.

Economic Contributions:

• Agriculture: The rivers are essential for agriculture, sustaining the livelihoods of a significant population.
• Industries: Major industries like leather tanning rely on these rivers for various processes.
• Inland Waterways: The rivers facilitate inland water transportation, contributing to economic activities.

Biodiversity and Natural Resources:

• Support Ecosystems: Himalayan rivers sustain a diverse range of species, contributing to the country's flora and wildlife.
• Forests: Natural resources such as forests depend on these rivers, influencing the region's ecological balance.

Global Impact:

• Economic Value: About half of the world's population is dependent on these rivers, highlighting their global economic significance.

Hydropower Generation:

• Enormous Potential: The Himalayan rivers offer significant hydropower generation potential.
• Projects: Initiatives like the Bhakra-Nangal project on the Sutlej River in the Outer Himalayas demonstrate India's pursuit of hydropower resources since the 1950s.
• In summary, the Himalayan drainage system plays a multifaceted role, impacting geology, ecology, agriculture, industries, and global economics. The rivers are a lifeline for the region, supporting diverse ecosystems and contributing significantly to India's economic and environmental well-being.

FAQs - Himalayan River System and Drainage

1-What are the major rivers in the Himalayan River system?

Ans. The major rivers in the Himalayan River system include the Indus, Ganga, and Brahmaputra.

2-What sustains the Himalayan rivers, making them perennial?

Ans. The Himalayan rivers are sustained by a combination of melting snow and precipitation, rendering them perennial.

3-How do the Himalayan rivers transform upon entering the plains?

Ans. Upon entering the plains, Himalayan rivers undergo transformations leading to the formation of depositional features like valleys, oxbow lakes, flood plains, braided channels, and deltas near the river's outlet.

4-What is the historical background of the Himalayan drainage system?

Ans. The Himalayan drainage system evolved during the Miocene period, with a colossal river named Shiwalik or Indo-Brahma spanning the Himalayan range. This river system later dismembered into three primary drainage systems.

5-What caused the dismemberment of the Himalayan drainage system?

Ans. The dismemberment is believed to have occurred during the Pleistocene period due to geological events, such as the elevation of the Potwar Plateau (Delhi Ridge) acting as a hydrological barrier, leading to the separation of the Indus and Ganga drainage systems.

6-How did the Ganga and Brahmaputra change their courses during the Pleistocene period?

Ans. The mid-Pleistocene down-thrusting of the Malda gap region redirected the Ganga and Brahmaputra systems towards the Bay of Bengal, shaping the contemporary configuration of the Himalayan drainage system.

7-Tell me about the Indus River system.

Ans. The Indus River system is one of the world's major river basins. The Indus, also known as Sindhu, originates in Tibet, flowing through Ladakh, Baltistan, and Pakistan, receiving tributaries like Shyok, Gilgit, and Zaskar. It ultimately empties into the Arabian Sea.

8-What are the major tributaries of the Indus River?

Ans. Major tributaries of the Indus include Shyok, Gilgit, Zaskar, Hunza, Nubra, Shigar, Gasting, Dras on the right bank, and Khurram, Tochi, Gomal, Viboa, Sangar on the left bank.

9-Can you provide information on the Satluj River?

The Satluj River originates near Mansarovar in Tibet, runs parallel to the Indus, crosses the Himalayas at Shipki La, merges with the Beas River, and enters Pakistan. It contributes to the Bhakra Nangal project's canal system.

10-Tell me about the Ganga River system.

Ans. The Ganga, India's most significant river, originates in Uttarakhand, meeting the Alaknanda at Devprayag to become the Ganga. The river system includes major tributaries like Yamuna, Ramganga, Gomati, Ghaghara, Gandak, Kosi, and Mahananda, ultimately emptying into the Bay of Bengal.

11-What are the key right bank tributaries of the Ganga?

Ans. Key right bank tributaries include Yamuna, Tamas, Son, and Punpun.

12-Can you elaborate on the Brahmaputra River system?

The Brahmaputra, originating in Tibet as Tsangpo, enters India as Siang or Dihang, receiving tributaries Dibang and Lohit. In Bangladesh, it joins the Padma River and empties into the Bay of Bengal.

13-What are the significant left and right bank tributaries of the Brahmaputra?

Ans. Key left bank tributaries are Burhi Dihing and Dhansari, while right bank tributaries include Subansiri, Kameng, Manas, and Sankosh.

14-What is the significance of the Himalayan drainage system?

Ans. The Himalayan drainage system is vital for North India, providing surface and groundwater for agriculture, industries, and inland waterways. It supports biodiversity, natural resources, and has global economic importance.

15-How do the Himalayan rivers contribute to hydropower generation?

Ans. The Himalayan rivers offer enormous hydropower generating potential, with projects like Bhakra-Nangal harnessing this potential since the 1950s.