State to move Cauvery Authority on 'surplus water'

Karnataka is staking claim on the right to use surplus water available in its Cauvery basin areas after ensuring 177.25 tmc feet to Tamil Nadu at Biligundlu in a normal year.

Karnataka says this is deemed as the Supreme Court judgment on Cauvery water dispute is silent on the use of surplus water after releasing Tamil Nadu its quota in a normal year.

Of the total 740 tmc ft of water in the Cauvery basin in a normal year, Tamil Nadu is entitled to 404.25 tmc ft, Karnataka 284.75 tmc ft, Kerala 30 tmc ft and Puducherry 7 tmc ft. Karnataka has to ensure 177.25 tmc ft of water at Billigundlu measuring site for Tamil Nadu in a normal year.

Though the figures for the exact quantum of excess water in the Cauvery basin in Karnataka in a normal year are not available, the state officials are doing the calculation of this water, including regeneration, to present before the Cauvery Water Management Authority, sources said. Karnataka has liberty to withdraw all water from its reservoirs and grow such crop and crops as the state decides after ensuring 177.25 tmc ft of water to Tamil Nadu at Billigundlu in a normal year or pro-rata share in the distress year as decided by the CWMA based on ground realities, said the state in its communication to the CWMA.

The state said that indication of distress in the Cauvery basin is possible only at the end of June after considering the inflows into four reservoirs. The final determination of distress should be at the end of water year - May 31 - against the normal yield of 740 tmc ft, it said. Karnataka also suggested the CWMA that the monthly determination of distress in the absence of monthly normal yield (monthly component of 740 tmc ft) is not possible and any ‘ad hoc’ determination will be prejudicial to the interests of Karnataka.

According to a format circulated by the Cauvery Water Regulation Committee (CWRC), a sub-committee of the CWMA, all the Cauvery basin states should submit their indent of water required by them every 10 days. Karnataka may insist that the Centre should seek the indent of water from states only during distress and not in a normal year.