The ruling will mark the culmination of the inter-state dispute that has seen widespread violence and protests over the years. It is expected that the court will put in place a scheme for peaceful and effective implementation of water sharing between the southern states.
The outcome of the legal battle ranging over a decade will also serve as a precedent on deciding water sharing disputes in the future.
The judgment will be passed on a batch of appeals by the states of Karnataka, Tamil Nadu and Kerala challenging the 2007 award passed by the Cauvery River Water Disputes Tribunal in which it determined the utilizable quantum of water of the Cauvery at 740 TMC feet.
The award had made an annual allocation of 419 TMC to Tamil Nadu in the entire Cauvery basin, 270 TMC to Karnataka, 30 TMC to Kerala, and 7 TMC to Puducherry. It was notified by the government in 2013.
A three-judge bench comprising Chief Justice Dipak Misra and justices Amitava Roy and A.M. Khanwilkar reserved the order on 20 September after the matter was heard on a regular basis.
Over the years, the apex court has passed a series of orders setting a limit to the amount of water to be released by Karnataka to Tamil Nadu.
The state of Tamil Nadu had informed the court on 12 July 2016 that Karnataka had failed to fully comply with a series of orders passed by the court regarding timely release of water from the Cauvery river.
In an affidavit, it was claimed that instead of releasing 22.55 TMC feet of water over a period of 25 days (from 6 September to 30 September 2016), as stipulated under the court’s directives, Karnataka had released only 16.58 TMC feet of water.
On 12 September 2016, the court asked Karnataka to release 12,000 cusecs of water per day for 7 days, revising its earlier order of 5 September to release 15,000 cusecs per day till 16 September.
The state was thereafter directed to release 6,000 cusecs of water a day to Tamil Nadu from 21 to 27 September on 20 September. This was extended for three more days until 30 September.
Between such times the state of Karnataka saw widespread violence and protests and approached the court seeking a week’s suspension in the order and a modification.
In another order of October 2016, the court had directed Karnataka to release 2,000 cusecs of Cauvery water every day to Tamil Nadu till further orders.
The court in December had said it was within its jurisdiction to hear appeals against the 2007 Cauvery Water Disputes Tribunal award after the centre and Puducherry opposed the appeals saying that the Constitution expressly ousts the jurisdiction of the apex court in inter-state river water disputes.
In 2007, Karnataka, Tamil Nadu and Kerala had approached the apex court in appeal against the 5 February 2007 award of the Cauvery tribunal that had determined the quantum of water in the river and set limits for its distribution among the states of Karnataka, Kerala, Tamil Nadu and Puducherry.
The award had also sought for setting up of a supervisory committee called the Cauvery Management Board (CMB) to give effect to the implementation of its order. This has not been put in place yet.
After opposition from the centre, the apex court constituted a nine-member panel headed by G.S. Jha, chairperson of the Central Water Commission (CWC), and comprising members nominated by Karnataka, Tamil Nadu, Puducherry and Kerala to resolve the water-sharing dispute.
Karnataka had contested the final verdict of the dispute tribunals, arguing that a major share of the water will go to Tamil Nadu, leaving almost six Karnataka districts, including Bengaluru, without enough water for drinking and farming. It opposed the release of water to Tamil Nadu during difficult years, building up tensions between both the states leading to violent conflicts on either side.
The Cauvery river basin, originates in Karnataka and flows through Tamil Nadu and Puducherry before it enters the Bay of Bengal. Off the total catchment area of 81,155 square kilometres, 34,273 kilometres is in Karnataka, 44,016 square km in Tamil Nadu and Puducherry and about 2,866 sq km is in Kerala.