SC to hear TN-Karnataka Cauvery dispute amidst deficit rainfall concerns

The Supreme Court will hear Tamil Nadu’s plea on the water to be released from the Cauvery river on 25 August, with the Karnataka government submitting an affidavit to put forth its stand on the matter.

Karnataka said it wants its stand to be heard so that it can protect the interests of the state and its farmers, while Tamil Nadu had approached the apex court so as to direct Karnataka to release 24,000 cusecs of Cauvery water daily for standing crops.

Karnataka wants to release water to the neighbouring state after taking into account the state’s needs for drinking water and irrigation for crops in the Cauvery river basin. What has caused this worry is the deficit rainfall in the Cauvery region.

In Karnataka, there has been water shortage in several districts since June, leading the government to prepare for a drought. Between June and mid August, Karnataka has recorded 499.4 mm of rainfall against the normal of 587.9 mm, which is a deficit of 15 per cent.

What is worrisome is that in August, the state has recorded only 29.6 mm of rainfall, when the normal is 135 mm for the month, with the Indian Meteorological Department predicting isolated rain in the state over the next two weeks. Kodagu district, where the Cauvery river originates, has seen a deficit of 91 per cent rainfall this monsoon.

Last week, the Cauvery Water Management Authority stated that Cauvery basin reservoirs in Karnataka were facing a 42.54 per cent shortfall in inflow owing to poor monsoon in the catchment areas. The water in the dams on the river in Karnataka — Krishna Raja Sagara Dam, Hemavathy dam, Harangi Dam and Kabini Dam — are all at low levels and well below capacity.

Tamil Nadu has had normal rainfall this season, but farmers in the region depend on Cauvery water for irrigation, which is why TN has sought the SC's directions asking Karnataka to release 24,000 cusecs from its reservoirs. The state also wants the top court to ensure that Karnataka releases 36.76 tmcft (thousand million cubic feet) as stipulated for the month of September, making good the shortfall of 28.849 tmcft for the period of 1 June to 31 July.

A direction was given to Karnataka on 10 August to release 15,000 cusecs at Billigundulu on 11 August for 15 days. However, this was reduced to 10,000 cusecs by the Cauvery Water Management Authority, said Tamil Nadu in court.

On 21 August, an SC bench of Justices BR Gavai, PS Narasimha and Prashant Kumar Mishra was constituted by Chief Justice DY Chandrachud to hear the issue after senior advocate Mukul Rohatgi, who was appearing for Tamil Nadu, sought an urgent hearing.

What is it all about?

Though the dispute had been raging since the late 1960s, the SC only intervened in 1990 and directed then Prime Minister VP Singh to constitute a tribunal. A Cauvery River Water Authority was constituted with the PM, and CMs of Karnataka, Tamil Nadu, Puducherry and Kerala.

The authority came up with proposals, but things came to a head again in 2002, when the monsoon failed in both Tamil Nadu and Karnataka.

In 2007, the Cauvery Water Disputes Tribunal gave its final verdict, against which Karnataka first went to the SC, followed by Tamil Nadu. Eventually, in 2018, the SC lowered the amount of water due to Tamil Nadu as allotted by the tribunal, to 404.25 tmcft from 419 tmcft. The SC also allotted Karnataka 270 tmcft, which is 14.75 tmcft more than the tribunal award. In a normal rainfall year, Karnataka has to release 177.25 tmcft of water to TN from the inter-state Biligundlu dam.

However, a 2018 Supreme Court order modifying clause 7 of the tribunal's order states, “In case the yield of Cauvery basin is less in a distress year, the allocated shares shall be proportionally reduced among the States of Kerala, Karnataka, Tamil Nadu, and Puducherry”.

But there is no mathematical model to calculate the distress. The quantum of rainfall during the southwest and northeast monsoons will be available only by January. Karnataka has been pointing out that if the southwest monsoon fails for Karnataka, and Tamil Nadu gets a good northeast monsoon, then Tamil Nadu cannot give the water back to Karnataka.