Kaveri

Kaveri Cauvery
Talakaveri, the source of Kaveri Kaveri at Srirangapatna Shivanasamudra Falls Hogenakkal Falls Confluence with Bhavani Kallanai Dam on the river
Kaveri River basin
Location
Country	India
Region	South India
States	Karnataka, Tamil Nadu, Kerala, Puducherry
Physical characteristics
Source	Western Ghats
• location	Talakaveri, Kodagu district, (Coorg) Karnataka
• coordinates	12°23′N 75°29′E / 12.383°N 75.483°E / 12.383; 75.483
• elevation	1,341 m (4,400 ft)
Mouth	Bay of Bengal
• location	Poompuhar, Mayiladuthurai district, Tamil Nadu
• elevation	0 m (0 ft)
Length	800 km (500 mi)[1]
Basin size	81,155 km2 (31,334 sq mi)[2]
Discharge
• location	Lower Anaicut (58.5 km upstream of mouth)
• average	919 m3/s (32,500 cu ft/s) (1998–2024)[3]
• minimum	144 m3/s (5,100 cu ft/s)[3]
• maximum	4,075 m3/s (143,900 cu ft/s)[3]
Discharge
• location	Grand Anicut (140 km upstream of mouth)
• average	400.716 m3/s (14,151.2 cu ft/s) (1976–1979)[4] 1,131 m3/s (39,900 cu ft/s) (1998–2024)[5]
• minimum	78 m3/s (2,800 cu ft/s)[5]
• maximum	4,916 m3/s (173,600 cu ft/s)[5]
Basin features
Tributaries
• left	Harangi, Hemavati, Shimsha, Arkavati, Sarabanga, Thirumanimutharu
• right	Lakshmana Tirtha, Kabini, Bhavani, Noyyal, Amaravati, Moyar

The Kaveri (anglicized as Cauvery),^[a] historically known in Tamil as Ponni (IPA: [ponːi]),^[6][7] is a major river flowing across southern India. It is the third-largest river in the peninsula after the Godavari and Krishna. The river basin covers an estimated catchment area of 81,155 km² (31,334 sq mi), across the states of Tamil Nadu, Karnataka, Kerala, and the Union Territory of Puducherry.

The river rises at Talakaveri in the Brahmagiri range of the Western Ghats, at an elevation of 1,341 m (4,400 ft) in the Kodagu district of Karnataka. It traverses approximately 320 km (200 mi) across the Deccan Plateau in Karnataka before entering Tamil Nadu, flowing a further 416 km (258 mi) eastward to empty into the Bay of Bengal near Poompuhar in Mayiladuthurai district. Over its total course of roughly 800 km (500 mi), major tributaries include Harangi, Hemavati, Lakshmana Tirtha, Kabini, Shimsha, Arkavati, Bhavani, Noyyal, and Amaravati.

Multiple dams and reservoirs along the river support regional irrigation systems and hydroelectric power generation. The river has supported agriculture in the region for centuries and historically supported early agricultural states, including the Chola and Pandya kingdoms. Sharing of its waters has been a long-standing Kaveri River water dispute between Karnataka and Tamil Nadu. The Kaveri River basin is a densely populated region, with several towns and cities located on its banks.

In Hinduism, the Kaveri is revered as one of the seven sacred rivers (Sapta Sindhu) and is personified as the goddess Kaveriamma. It is praised in Sanskrit epics including the Mahabharata and various Puranas, as well as throughout classical Sangam literature.

Kaveri is mentioned in Sanskrit literature, including the Mahabharata and the Puranas, as a sacred river.^[8] The name itself might have had different etymologies. According to a legend in the Skanda Purana, the river originated when Ganesha, in the guise of a crow, overturned sage Agastya's kamandala (water vessel). Linguistically, the name Kaveri has been derived from Dravidian roots, such as the Kannada terms ಕಾವಿ (Kāvi): Red ochre, saffron, or reddish-brown clay and ಏರಿ (Ēri): A watercourse, bank, bund, or elevated stream channel. An alternative derivation links it to viri (to spread out or wide banks).^{[8][9][10][11]} The term kāviri alos occurs in the Sankethi dialect to denote a river.^[12] The spelling Cauvery is an anglicization done during the colonial period.^[11]

In classical Tamil literature, the river is frequently called Ponni (meaning "the golden one"), in reference to the gold-colored fertile silt it deposited along its delta during floods.^{[9][13][14][15]} In Sanskrit traditions, it is also known as Daksina Gaṅgā (Ganges of the South),^[16] and Ardha Gaṅgā (Half Ganga) due to its mythological association with the celestial Ganges.^[8] Some scholars also identify it with the Rigvedic river name Marudvṛdhā (rejoicing with the Maruts).^[17]

The river rises at Talakaveri in the Brahmagiri Hills of the Western Ghats,^[18] located at an elevation of 1,341 m (4,400 ft) in the Kodagu district of Karnataka.^[1] Its upper course passes through rocky terrains and steep banks before flowing eastward through a series of rapid falls. Flowing onto the Deccan Plateau through a narrow gorge, the river drops about 18–24 m (59–79 ft) at Chunchanakatte Falls.^[16] It then forms the river island of Srirangapatna and widens to 270–370 m (890–1,210 ft) before turning south-east.^[16][18] At Shivanasamudra, it drops 91 m (299 ft) to form the Shivanasamudra Falls, one of the largest waterfalls in the country.^[1][18] After forming the island of Shivanasamudra, the river converges and passes through the Mekedatu gorge.^[1][19] After traversing 320 km (200 mi) within Karnataka, the river forms the Karnataka–Tamil Nadu border for roughly 64 km (40 mi).^[1]

Upon entering Tamil Nadu, the river forms the Hogenakkal Falls,^[18] before continuing south toward the Mettur Dam, where it is joined on its right bank by River Bhavani at Kooduthurai.^[1][19] Flowing eastward through Erode and Karur, it enters Tiruchirappalli district and bifurcates into northern Kollidam and southern Kaveri.^[1] The two branches form the river island Srirangam^[1][19] before diverging across an extensive delta of 36 distribution channels. It ultimately discharges into the Bay of Bengal near Poompuhar in Mayiladuthurai district.^[20] The river traverses for about 416 km (258 mi) in Tamil Nadu, bringing its total length to approximately 800 km (500 mi).^[1]

The Kaveri basin was formed between the Late Jurassic and Early Cretaceous periods during the breakup of Gondwana and the opening of the Indian Ocean.^[21] Most of the basin is underlain by Precambrian metamorphic and igneous basement rocks.^[19] Closepet Granite is found in the upper catchment, while charnockite rocks are found in the central basin.^[18] A 2017 study proposed that presence of putative meteorite impact structure in the vicinity of the basin.^[22] The basin's topgraphy prevents rapid run-off, reducing the frequency of flash floods. The river maintains perennial flow supported by dual monsoon cycles: the southwest monsoon in Karnataka and the northeast monsoon in Tamil Nadu.^[1]

According to a 2014–15 government assessment, the basin generates nearly 3.5 million metric tons of dissolved salts annually, with an average salinity of 441 ppm, close to the standard maximum limit of 500 ppm.^[23][24][25] Increased population density and agricultural runoff have increased salt inputs, while salt export is hindered by reduced fresh water discharge to the sea.^[26][27] This degrades basin water quality.^[28][29][30]

The basin encompases forest and agro–ecological zones,^[31] with forest types ranging from moist evergreen and dry deciduous forests to grasslands.^[32] A remote-sensing study found that approximately 12,850 km² (4,960 sq mi) of natural vegetation was lost in the basin between 1965 and 2016.^[33] Regional flora includes species such as Terminalia arjuna, Tamarindus indica, Pongamia pinnata, Salix tetrasperma, Ficus benghalensis, Ficus religiosa, Eucalyptus torticornis, and Diospyros montana.^[31]

The basin contains several protected areas that support populations of Bengal tiger, Indian elephant, gaur, leopard, sloth bear, Nilgiri tahr and grizzled giant squirrel apart from various species of deer, wild boar and reptiles.^[32] Avifauna includes the painted stork (Mycteria leucocephala), spot-billed pelican (Pelecanus philippensis), and black-headed ibis (Threskiornis melanocephalus). Aquatic wildlife includes the mugger crocodile (Crocodylus palustris), smooth-coated otter (Lutrogale perspicillata), and the critically endangered hump-backed mahseer (Tor remadevii).^[34]

Dams and flow regulation structures have fragmented the longitudinal and lateral connectivity of the river, disrupting aquatic habitats and migratory fish routes. The reduction of sediment, nutrient, and freshwater delivery has impacted estuarine ecosystem in the delta. Reduced stream flows and suppressed natural flow pulses have caused steep declines in migratory fish populations. Seasonal low-flow conditions threaten the survival of the endemic and endangered hump-backed mahseer.^{[35]: 2, 15}

The Kaveri basin covers a total catchment area of 81,155 km² (31,334 sq mi), comprising 43,856 km² (16,933 sq mi) in Tamil Nadu, 34,273 km² (13,233 sq mi) in Karnataka, 2,866 km² (1,107 sq mi) in Kerala, and 160 km² (62 sq mi) in the Union Territory of Puducherry.^[2][1] Over half of the basin is arable land, with rice and sugarcane being the primary crops.^[31] During the first Five-Year Plan, the total flow of the river was estimated at 15 cubic kilometres (12,000,000 acre⋅ft), of which approximately 60% was utilized for irrigation.^[36] The river also provides drinking water and supports hydroelectric power generation.^[16][37]

About 96 dams have been built across the Kaveri basin over the past millennium, most of which are small-scale barrages and weirs. Irrigation is the primary function for 70.30% of these structures, followed by hydroelectric power generation (19.80%), combined irrigation and power (6.93%), and municipal drinking water supply (2.97%).^[35]: 3

The ancient Grand Anicut (Kallanai) was constructed during the early Chola period in the 2nd century CE.^[1] Modern infrastructure began with the Shivanasamudra hydroelectric installation in 1902, one of the earliest major hydroelectric plants in Asia.^[38] In Tamil Nadu, the Mettur Dam was completed in 1934 forming the Stanley Reservoir with a gross storage capacity of 93.4 tmc ft (2.64 km³).^[16][39] In Karnataka, the Krishna Raja Sagara dam, completed in 1938, is the second-largest reservoir on the river with a capacity of 49.5 tmc ft (1.40 km³).^[39][40] Principal tributary storage projects include the Bhavanisagar Dam (32.8 tmc ft) on the Bhavani River in Tamil Nadu, as well as the Gorur dam (37.1 tmc ft) on the Hemavathi, the Kabini Dam (18.5 tmc ft) on the Kabini, and the Harangi Dam (9.5 tmc ft) on the Harangi in Karnataka.^[2][39] Although these rivers expanded the basin's irrigation coverage, water retention has aggravated political disputes over water sharing between upstream and downstream states.^[35]: 2

Water dispute

[edit]

Further information: Kaveri River water dispute

The dispute over the sharing of Kaveri waters began in 1807 when the Madras Presidency objected to the plans of the Mysore kingdom to develop irrigation projects. After initial discussions failed, the British Raj intervened and a six rule agreement called the General Agreement of 1892 was signed.^[41] The agreement was revised in 1924, with a validity of fifty years. After the expiry of the 1924 agreement in 1974, Karnataka demanded a renegotiation and its due share of water from the river while Tamil Nadu favored an extension of the agreement.^[42][43][44] After Indian Independence, article 262 of the Constitution of India provided powers to the Government of India to adjudicate on inter-state disputes on water sharing.^[45] The union government constituted the Cauvery Water Disputes Tribunal (CWDT) on 2 June 1990, based on the order of the Supreme Court of India, to adjudicate the water dispute between the riparian states and territories in the river basin. The tribunal gave an interim award on 25 June 1991 that was based on its 10-year calculation of average inflow of water from Karnataka into Tamil Nadu.^[42][44] In the order passed on 25 June 1991, the CWDT directed Karnataka to release 205 tmcft of water per year to Tamil Nadu based on a specific schedule. The water was to be released in four equal installments in a particular month and any shortfall would need to be covered in the subsequent week. Tamil Nadu was directed to provide 6 tmcft of water to Puducherry.^[2]

In July 1991, the president asked the Supreme Court to rule on the validity and legality of the tribunal under the Constitution. In November 1991, the Supreme Court opined that the order needs to be published by the central government in the official gazette, which was done on 1 December 1991.^[2] In May 1992, the Government of Tamil Nadu filed a case in the Supreme Court to direct the union government to pass necessary orders to ensure the implementation of the provisions of the tribunal order. In April 1997, the attorney general reverted that the central government has prepared a scheme under the Inter-State Water Disputes Act, 1956 for the implementation of the tribunal award and the Cauvery Water Authority (CRA) and Cauvery Monitoring Committee (CMC) were formed subsequently as a part of the Cauvery Water (Implementation of Interim Orders of 1991 and all subsequent Tribunal Orders) Scheme, 1998. The CRA is headed by the prime minister and consists of the chief ministers of the riparian states as its constituent members.^[2]

The dispute arose periodically such as in 1995 and 2002, when poor monsoon led to lower water levels.^[44] This led to instances where the Supreme Court and the CRA had to intervene, and had led to instances of violence, arson, and protests in Karnataka and Tamil Nadu.^[46][47] The CWDT announced its final verdict on 5 February 2007. According to its verdict, Tamil Nadu was awarded 419 tmcft of the Kaveri river waters while Karnataka got 270 tmcft, with Kerala and Puducherry getting 30 tmcft and 7 tmcft respectively. It also laid down the terms for monthly release of water from Karnataka to Tamil Nadu.^[48][49]

After further disputes in 2012, and the intervention of the Supreme Court,^[50] the Indian Government notified the final award in the gazette on 20 February 2013.^[48][51] However, after further disputes in 2016,^[52] and further appeals by the concerned states, the Supreme Court ruled on 16 February 2018, that Karnataka will get 284.75 tmcft, Tamil Nadu will get 404.25 tmcft, Kerala will get 30 tmcft and Puducherry will get 7 tmcft of water from the river basin. An additional 10 tmcft was reserved for environmental protection and 4 tmcft was reserved for wastage into the sea.^[53] The court directed the government to form a Cauvery Water Management Authority (CWMA) within six weeks and acting on the Supreme Court's direction, the central government constituted the CMWA in June 2018.^[54][55][56]

In Hinduism, the Kaveri is revered as one of seven sacred rivers (Sapta Sindhu) of India, personified and worshiped as the goddess Kaveri Amma.^[8][57] She appears in classical Sanskrit texts, including the Mahabharata and the various Puranas as both a sacred river and a goddess. According to Shiva Purana, the Kaveri is one of the seven holy Gangas and ritual bathing in its waters is believed to grant one's desires. The Varaha Purana describes it as originating from five mountains and that it grants longevity to those who drink from it. In the Skanda Purana, Shiva places the Kaveri into the Kamandala (water vessel) of sage Agastya, which is overturned by Ganesha to release the river.^[8][9]

Another tradition equates Kaveri with Lopamudra, the wife of Agastya. She—having taken the form of water—is being carried by Agastya in his Kamandala. Ganesha, in the form of a crow, knocks the water pot down. This spilled water becomes the river that quells the draught in south India.^[58] Another traditional story narrates that following the Samudra Manthana (churning of the Ocean of Milk), Mohini and Lopamudra retrieved the nectar of immortality for the gods. Lopamudra was then raised by Brahma and was later given to king Kavera, who named her Kaveri. She prayed to Brahma to become a purifying river.^[57]

In classical Tamil epic Manimekalai, Agastya swallowed the Ganges when the floodwaters disturbed his tapas (penance), later releasing it in southern India as Kaveri. Cilapathikaram mentions Kaveri as the daughter of Kavera. In Theravada Buddhism, Kaveri is mentioned as a water channel. It is part of the twenty canal-systems associated with the reservoir Parakkamasamudda that existed in the Polonnaruwa region during the reign of king Parakramabahu I.^[8]

Kaveri Pushkaram is a Hindu festival dedicated to the river.^[59] It is generally observed once every 12 years,^[59] with a "Maha Pushkaram" held every 144 years.^[60][61] The key pilgrimage sites include Srirangam and Thula Kattam at Mayiladuthurai near the mouth of the river.^[60][61] The festival is celebrated for 12 days, and includes ceremonial observations such as homam, yagnam, chanting of the Vedas, ritual feeding, and tharpanam accompanied by cultural activities such as music, dance, and spiritual speeches.^[61]

The Kaveri river faces pollution from untreated household sewage, industrial waste and wastewater from coffee plantations.^[62] A scientific study found dangerous levels of heavy metals like lead, copper and mercury in the river's sediment, as well as high amounts of hormone-disrupting chemicals that can cause cancer, infertility; and hormonal disruptions in humans and wildlife.^[63] To protect the river, the Karnataka State Pollution Control Board has setup monitoring stations, urged local city governments to stop untreated waste dumping, and called on citizens to segregate waste.^[62]

• List of rivers of India
• Kaveri Pushkaram