The Cauvery Water Management Authority (CWMA), which met in Delhi on Tuesday (August 11, 2026), affirmed and endorsed the decision by the Cauvery Water Regulation Committee (CWRC) to direct Karnataka to ensure the release of Cauvery water at the rate of 12,000 cusecs a day from Wednesday for the next 15 days to neighbouring Tamil Nadu.

This means that Karnataka would have to provide about 15.55 thousand million cubic feet (tmc ft), considering that the flow of 11,574 cusecs in 24 hours equals one tmc ft.

Responding to this, Karnataka Chief Minister D.K. Shivakumar said a decision on the next course of action would be taken after carefully assessing the water availability in the State. He stressed the need to protect the interests of State’s farmers while also complying with the orders of the Authority and the CWRC. He is set to hold a meeting with legal experts and bureaucrats on Wednesday (August 12, 2026) on the possible legal options.

CWMA chairperson Saumitra Kumar Haldar told The Hindu later that Karnataka “is in a comfortable position” to comply with its order. The CWMA arrived at the decision after considering the storage, inflows, and the meteorological outlook for the next seven days, he said.

Karnataka’s argument

Earlier, Karnataka appealed to the CWMA to defer any decision on further releases and take a considered decision based on actual hydrological realities at the end of the South-west monsoon season. If not, it pleaded, the CWMA should at least reduce the quantum of water release from 12,000 cusecs a day to 10,000 cusecs.

Karnataka told the CWMA that the Cauvery basin was “reeling under severe hydrological distress”. It pointed out that all four reservoirs in the Cauvery basin had received only 77.746 thousand million cubic feet (tmc ft) of cumulative inflows in this water year, which was “about 47% less” than the 30-year average. Also, the inflows to the reservoirs were rapidly declining, it said.

Karnataka argued that it had already ensured flows of 86,942 cusecs at Biligundlu [the measuring point of Cauvery flow on the inter-State boundary] as against the prescribed quantum of 52,500 cusecs by the CWMA. It argued that the realisation by Tamil Nadu was bound to be much more as additional flows too were in transit

It argued that there was no scope for further water release to the neighbouring State given its own “deficit monsoon, dwindling inflows and limited storage.” Also, there was a dire need to conserve water for drinking and essential uses besides taking care of farmers’ kharif crop.

Karnataka contended that Tamil Nadu, in contrast, was “in an advantageous position” as it already had “sufficient storage” in its reservoirs besides having the benefit of forthcoming north-east monsoon as well as any downstream flows.

The State said that distress sharing must be equitable, while contending that a rigid, predetermined pro-rata formula based solely on inflows into Karnataka’s reservoirs could “disproportionately burden the State”. Karnataka further demanded that a broader system be put in place to assess distress based on the situation across the entire basin, rather than merely on inflows to its four reservoirs.

TN’s demands and arguments

On its part, Tamil Nadu appealed to the CWMA to direct Karnataka to ensure releases of 37 tmc ft at Biligundlu by August end, taking cognisance of the backlog and the quantum that is due on pro-rata basis from August 13 to 31.

It argued that maintaining the entire one year’s drinking water requirement for Bengaluru as a contingency plan against any worst-case scenario was not justified and should not be used to deny its legitimate share.

Tamil Nadu argued that its basin area experienced a much higher rainfall deficit of 36% so far in this water year, compared with the 9% deficit in upstream of KRS and 19% in that of Kabini.

Tamil Nadu maintained that the present substantial downstream flow to it was largely due to surplus flow from Kabini and contended that despite improved inflows into the KRS catchment, releases from this reservoir had remained low, indicating issues related to equitable sharing of available flows. It appealed to the CWMA to direct Karnataka to regulate releases from both KRS and Kabini.

It argued that Karnataka’s projection of substantial benefit to Tamil Nadu from the north-east monsoon “lacked adequate scientific basis.”

CWMA stance

The CWMA chairperson said its decision was based on a number of factors. As “against the long term average of 83 tmc ft at four reservoirs of Karnataka in the Cauvery basin, the current storage is 77 tmc ft”, Mr. Haldar said. Besides, the upper riparian State’s reservoirs would be receiving 2 to 2.5 tmc ft a day at least for the next one week. “It is for this reason that we have decided that Karnataka can spare one tmc ft a day to Tamil Nadu,” Mr. Haldar observed.

While the upper riparian State wanted the Authority to settle for 9,000-10,000 cusecs (0.78 tmc ft to 0.86 tmc ft a day), Tamil Nadu, the lower riparian State, had sought the release of 1.5 tmc ft a day.

Referring to the circumstances under which the CWMA decided on July 30 to go by the CWRC’s position, Mr. Haldar said, “We were not sure how the southwest monsoon would behave. Even the meteorological forecast, both from the Indian Meteorological Department and Skymet, was not positive. As there was a 50% deficit in realisation at Biligundulu, we had asked Karnataka to release about 4.5 tmc ft. But, the rain started from then on.”

As for the need for a “permanent, scientific” distress-sharing formula, Mr. Haldar replied that “given the conditions that characterise the basin, there is no single formula that will work in the case of the Cauvery, as dynamics keep on changing”. However, he had sought views of the riparian States to come up with a formula, the chairperson added.

Published - August 11, 2026 10:45 pm IST