The Cauvery river rises on Brahmagiri Hill of the Western Ghats in Karnataka.
The Supreme Court on Thursday refused to interfere with the order of the Cauvery Water Management Authority (CWMA) and the CWRC directing the Karnataka government to release 5,000 cusecs of water per day to Tamil Nadu for 15 days.
The Cauvery Water Regulation Committee (CWRC) in its September 12 order, which was upheld by CWMA, directed Karnataka to release 5,000 cusecs (cubic foot per second) of water every day for the next 15 days to Tamil Nadu.
A bench of Justices BR Gavai, PS Narasimha and Prashant Kumar Mishra said it was not inclined to entertain Tamil Nadu's plea challenging the CWMA decision on the ground that it was facing a drought-like situation due to rain deficit.
The bench noted that bodies like CWMA and CWRC, which have experts from the India Meteorological Department (IMD), and those on agriculture and water resource management, have considered all relevant aspects like drought, deficit rainfall, water level in the river and only then passed the order.
"We are therefore of the considered view that the factors which have been taken into consideration by both the authorities cannot be said to be irrelevant or extraneous. In that view, we are not inclined to interfere with the orders," the bench said.
It noted the two authorities are meeting every 15 days to take stock of the distress faced by both the states.
Senior advocate Mukul Rohatgi, appearing for Tamil Nadu, submitted that the two authorities, despite having acknowledged there was deficient rainfall since August and the state was eligible for of 7,200 cusecs of water, reduced the volume to 5,000 cusecs a day.
"I am a low riparian state...water flows from Karnataka to Tamil Nadu from where it goes to Puducherry. There is a shortfall of rainfall which has been taken into consideration by the authorities. In a regular year, I would have been eligible for three times more but I am not seeking that. I am seeking what is rightfully mine," Rohatgi said.
He added Tamil Nadu has five lakh acres of standing crop and is facing a drinking water problem for which more water is needed.
"If the drought-like condition was taken into account and the authority calculated it to be 7,200 cusecs per day, then there was no occasion to further bring it down to 5,000 cusecs per day," he submitted.
Senior advocate Shyam Divan, appearing for Karnataka, said the upper riparian state was also facing drought-like conditions, and the release of 5,000 cusecs of water ordered by the authorities is against the "interest of the state". He insisted it should be further reduced to 3,000 cusecs per day. He said Karnataka uses Cauvery water for drinking as well as irrigation purposes while Tamil Nadu utilises it only for irrigation.
"We are facing a drinking water crisis, especially in urban areas including in Bengaluru," he said.
The bench then asked what the Centre has to say on the dispute over water sharing. Additional Solicitor General Aishwarya Bhati, who represented the Centre, said contrary to the claims made by the two states drought is not the only criteria which has been taken into account by CWMA before making the decision.
"They have taken into account IMD data, rainfall, water level in reservoirs and other relevant data after which they have arrived at the figure of 5,000 cusecs," Bhati said, adding the CWMA order has not been defied and water is being released to Tamil Nadu.
The bench then told Rohatgi the court is not inclined to entertain Tamil Nadu's petition.
On August 25, the top court had refused to pass any order on the Tamil Nadu government's plea seeking release of 24,000 cusecs of Cauvery water daily by Karnataka for irrigating the standing crops.
The Supreme Court had sought a report from the CWMA on the amount of water released by Karnataka.
Rainfall has been 25 per cent lower and water inflow into Karnataka's four reservoirs 42.5 per cent lesser, an affidavit filed by the upper riparian said, adding the stipulated release shall not be applicable this year.
The Karnataka government said in the affidavit the southwest monsoon has largely failed so far during the current water year. A "distress condition" has arisen in the Cauvery basin in Karnataka, it said.
"Karnataka, therefore, is not obliged to and it cannot be compelled to ensure water as per the stipulated relief is prescribed for the normal year," the affidavit stated.
A bench headed by Chief Justice of India DY Chandrachud had earlier said a fresh bench will be set up to hear the decades-old dispute between Tamil Nadu and Karnataka over sharing of the Cauvery river water.