The Cauvery water dispute explained

The 150-year-old dispute born of geography and hydrology, shaped by politics, and now, exacerbated by the climate crisis

In Karnataka’s Mandya, protests are underway over the sharing of Cauvery water with neighbouring Tamil Nadu following the Supreme Court’s refusal last week to interfere in the enforcement of the water-sharing agreements between the states and the decisions of the Cauvery Water Management Authority and Cauvery Water Regulation Committee.

The Cauvery starts from the catchment area in the Brahmagiri Hills at Talakaveri in Coorg district and passes through four districts of Karnataka before entering Tamil Nadu at Dharmapuri district. (File Photo)

And with both sides now hardening their positions, a 150-year-old dispute may well have entered a new phase. It is a dispute born of geography and hydrology, shaped by politics, and now, with extreme weather events increasing in intensity and frequency, exacerbated by the climate crisis.

First, the geography.

The Cauvery starts from the catchment area in the Brahmagiri Hills at Talakaveri in Coorg district and passes through four districts of Karnataka before entering Tamil Nadu at Dharmapuri district. It has 21 principal tributaries --- nine in Karnataka and the rest in Tamil Nadu. It is the third largest river in southern India after Godavari and Krishna, and the largest in Tamil Nadu.

The river is crucial for farmers in the two states with paddy being the principal crop in the Cauvery delta. Karnataka has two seasons—kharif (monsoon sown) and rabi (winter), while farmers in Tamil Nadu have three harvests—kuruvai (June-September), thaladi (October to December), and samba (August-January), said Lakshmana Gowda, 71, one of the women protesting in Mandya since August 17, when the Cauvery Water Management Committee asked Karnataka to release 5,000 cusecs of water every day to Tamil Nadu. Farmers in Tamil Nadu argue that because they get less water from Cauvery they have resigned themselves to only two seasons.

The history

Disputes to do with water sharing are as common as they are enduring in India. Punjab and Haryana have been sparring over sharing the Sutlej; Odisha and Chhattisgarh over the Mahanadi; Andhra and Telangana over the Godavari; Kerala and Tamil Nadu over the Periyar; and Karnataka and Goa over the Mhadei. The Central government enacted the Interstate Water Disputes Act in 1956 to help resolve them, but the Cauvery dispute predates the passage of that law by at least 75 years.

In the mid-19th century, the British exercised control over Mysore and Madras states. During this period, there were several proposals for harnessing the waters of the Cauvery. However, these plans were shelved due to a severe drought and ensuing famine in the mid-1870s.

In 1881, Mysore decided to resurrect the demand for these irrigation projects. By this time, Mysore was ruled by its native kings, while Tamil Nadu remained under the administration of the Madras Presidency. Mysore’s plans to revive the irrigation projects met with resistance from the Madras Presidency.

“There was always a fear among the British that any reservoir construction would affect the interest of the Madras presidency. In fact, it was not just the British. Even the Chola soldiers used to destroy any bunds built by farmers to store water. In 1701, the Kannambadi dam was constructed first by Chikka Devaraja Wodeyar. It was about 30 feet in height. But it was damaged by the Tamilians,” said irrigation expert N Narasimhappa.

“The demand for reservoirs is old in the Mysore Kingdom. There is a Persian inscription which dates back to 1794, where Tipu Sultan laid the foundation of the Mohyi Dam across Cauvery,” he added.

The 1892 agreement

A series of meetings were convened in 1890 under the British, leading to the Agreement of 1892 between the Madras presidency and the rulers of Mysore, which remains the basis of water-sharing negotiations between Karnataka and Tamil Nadu.

The agreement allowed Mysore to build some new irrigation projects on five tributaries of the Cauvery but ensured Madras’s water interests would be safeguarded as per the estimate for drinking water and agriculture needs.

The most important aspect of the agreement was the need for prior consent of the Madras Presidency for new irrigation projects over the Cauvery or its tributaries. Clause three of the agreement read: “When the Mysore Government desires to construct any ‘New irrigation Reservoir’ or any new anicut requiring the previous consent of the Madras Government under the last preceding Rule, the full information regarding the proposed work shall be forwarded to the Madras Government and the consent of that Government shall be obtained previous to the actual commencement of work.”

The first fight

In 1910, tensions flared up when Mysore, under the leadership of King Nalvadi Krishnaraja Wodeyar and Chief Engineer Captain Nicholas Dawes, announced a proposal to build a dam in the village to store a substantial 41.5 TMC (Thousand Million Cubic Feet) of water.

The plan faced stiff opposition from Madras, which had its own ambitious scheme to construct a storage dam in Mettur with a much larger capacity of 80 TMC. The proposal would have not allowed enough water for the Mettur dam.

After referring the matter to the British Government of India, Mysore was granted permission for construction, albeit with a reduced storage capacity of 11 TMC. However, during the actual construction process, the foundation was laid to accommodate the originally desired full storage capacity, intensifying the dispute with Madras. As a result, the British Government of India opted to resolve this contentious issue through arbitration. This marked the first arbitration process in the ongoing Cauvery water dispute.

After a series of meetings and discussions from 1910 to 1924, both Mysore and Madras reached a consensus marked by the signing of the 1924 Agreement. This agreement had a remarkably long-term horizon; it was to remain in effect for 50 years. These agreements enabled both Mysore and Madras to successfully complete their respective projects. Mysore constructed the Krishna Raja Sagar dam at Kannambadi, boasting a capacity of 45 TMC, while Madras undertook the construction of the Mettur Dam, designed to hold a substantial 93.5 TMC.

“In fact, prior to this agreement, M Visvesvaraya, who was responsible for the construction of the reservoir convinced the Madras presidency saying that the reservoir was important to provide electricity to John Taylor company for mining gold in Kolar, and over the period of time got permission for irrigation,” Narasimhappa added.

The 1924 Agreement established specific limits, with Mysore being allocated up to 110,000 acres of irrigated land, and the Madras government agreeing to restrict new areas of irrigation from the Mettur project to 301,000 acres, resulting in two different crop seasons, with Madras getting additional irrigated land during its crop season.

The agreement mentioned that the limitations outlined in the agreement on irrigated areas could be reconsidered after the passage of 50 years. “The reconsideration was to be in the light of experience gained and of an examination of the possibilities of the further extension of irrigation within the territories of the respective governments and to such modification and additions as may be mutually agreed upon,” read the agreement.

The 1892 and 1924 Agreements played a pivotal role in bringing the stretch of the Cauvery River between the Krishna Raja Sagar Dam and the Mettur Dam to the forefront of the Cauvery water dispute. The 1924 agreement provided that Tamil Nadu would receive 75% of the water, Karnataka, 23%, and Kerala, the rest.

State reorganisation and beyond

The dispute continued to be a contentious issue. After India gained Independence, Parliament passed a law in 1956 to deal with interstate water issues. Receiving 75% of Cauvery water, Tamil Nadu had expanded its irrigated areas; Karnataka faced restrictions due to the 1924 agreement. But despite the friction, both states adhered to it.

By the late 1960s, both the states and the Union government began to realise the gravity of the situation as the 50-year run of the 1924 agreement was soon coming to an end. The then Water Resources Ministry started negotiations with the two states in the 1960s.

Two years before the expiry of the 1924 agreement, there was a water shortage due to insufficient rainfall. Tamil Nadu requested water from the KRS dam to safeguard crops in the Tanjore region. The Central Government under then Prime Minister Indira Gandhi tried to intervene by proposing a new draft agreement in 1974. However, the imposition of Emergency and the subsequent President’s Rule in Tamil Nadu derailed the mediation process.

The courts

In 1983, a farmer’s association from Thanjavur, Tamil Nadu, moved the Supreme Court (the state followed with its own one in 1987) demanding the establishment of a tribunal to adjudicate the issue. The court initially directed the parties to negotiate. However, upon their failure in April 1990, the Supreme Court finally directed the Central Government to constitute the tribunal.

In 1991, then Prime Minister PV Narasimha Rao presided over the Cauvery River Water Tribunal, which conducted an aerial survey of drought-affected areas. Based on this, it issued an interim decision on June 25, 1991. This decision directed Karnataka to ensure an annual release of 205 TMC of water to Tamil Nadu and halted its plans to expand irrigated land. The tribunal’s decision faced resistance from Karnataka, leading to riots in both states. Karnataka sought to annul the tribunal’s award, but the Supreme Court upheld it, leading to further discontent. Disputes continued to arise, and in 1993, Tamil Nadu farmers, led by Chief Minister J Jayalalitha, protested demanding more water.

In 1995, the tribunal allocated 230 TMCFT of water to Tamil Nadu, while imposing restrictions on Karnataka’s irrigation projects. Karnataka expressed concerns about unequal treatment. But these were interim awards. Over 17 years, the tribunal held 502 sittings and pondered over large volumes of evidence running up to fifty thousand pages. It delivered its final award on February 5, 2007, upholding the validity of the agreement of 1924 but in a modified form as per equitable consideration to address the historic grievances of Karnataka. Tamil Nadu was allocated 419 TMC, and Karnataka received 270 TMC.

The tribunal specified monthly deliveries at the interstate border, Biligundlu. However, the tribunal’s allocation lacked clarity during distress years, which continued to fuel disputes over water-sharing arrangements. In 2013, the central government notified the final award. Tamil Nadu’s Chief Minister, Jayalalithaa, sought the formation of the Cauvery Management Board, but this request remained unfulfilled. Disputes persisted, especially in years with inadequate rainfall.

The 2018 verdict

Following the appeals filed in 2012-13 and 2015-16, the Supreme Court issued a series of interim orders regarding water delivery, which sparked widespread protests in Karnataka. Eventually, the Supreme Court’s division bench decided to address the appeals and resolve the matter. The court spent an unprecedented 28 days meticulously reviewing a staggering 25,000 pages of documents.

On February 16, 2018, the Supreme Court issued a unanimous judgement that partially granted Karnataka’s appeal. This decision led to a reduction in Karnataka’s annual water releases from 192 TMC to 177.25 TMC.

The court also disagreed with the tribunal’s position that limited Bangalore city’s entitlement to one-third of its water requirement based on the fact that only a third of its territory fell within the Cauvery basin region. It allowed an additional allocation of 14.75 TMC for Bengaluru with 4.75 TMC designated for meeting Bangalore’s drinking water needs and the remaining 10 TMC for irrigation in drought-prone areas.

It said in its order that “being in a state of flow, no state can claim exclusive ownership of such waters or assert a prescriptive right to deprive other states of their equitable share.”

On the court’s direction, the Centre on June 1, 2018, established the Cauvery Water Management Authority to implement the judgement.

The latest turn

On August 14, the Tamil Nadu government approached the Supreme Court, seeking its intervention in compelling Karnataka to immediately release 24,000 cubic feet per second (cusecs) of water from its reservoirs. Tamil Nadu urged the Court to direct Karnataka to adhere to the release of 36.76 TMC of water, as stipulated for September 2023 in accordance with the Cauvery Water Disputes Tribunal (CWDT)’s final award of 2007.

Karnataka argued that lower rainfall in the Cauvery catchment area, including regions in Kerala, resulted in insufficient inflow into its reservoirs. Chief Minister Siddaramaiah explained that historically, whenever there was surplus water in the reservoirs, Karnataka had willingly released it to Tamil Nadu. However, this year, due to unfavourable conditions, Karnataka finds itself unable to do so.

He added that the Kodagu district (the source of the Cauvery River), experiencing a rainfall deficit, received 44% less rainfall between June 1 and August 15 than what was anticipated.

After the matter reached the court, The Supreme Court on Thursday refused to interfere with orders of the Cauvery Water Management Authority and Cauvery Water Regulation Committee, directing Karnataka to release 5,000 cusecs of water to Tamil Nadu. On September 18, The Cauvery Water Management Authority asked Karnataka to continue releasing 5,000 cusecs (cubic feet per second) of water to Tamil Nadu for 15 days, upholding The Cauvery Water Regulation Committee’s (CWRC) September 12 order demanding the same.

Lakshmana Gowda wants the “historic” injustice to Karnataka to be undone to save their crops. “Tamil Nadu wants water for their third crop cycle, while we are struggling to keep the first crop alive,” she said.

“We want justice," she added.