Chennai/New Delhi: The long-running Cauvery water dispute has entered another tense phase, with Tamil Nadu Chief Minister C. Joseph Vijay writing to Prime Minister Narendra Modi and urging the Union government to block Karnataka’s proposed Mekedatu dam project across the Cauvery river. The intervention comes after fresh legal and administrative movement around Karnataka’s plan, including the Supreme Court’s dismissal of Tamil Nadu’s review petition and renewed efforts by Karnataka to advance its Detailed Project Report.
Vijay has asked the Prime Minister to direct the Ministry of Jal Shakti and the Central Water Commission to reject Karnataka’s DPR for the Mekedatu project. His core argument is that no new project across the Cauvery should move forward without the prior consent of the co-basin states, including Tamil Nadu, Kerala and Puducherry.
“For Tamil Nadu, Mekedatu is not merely an infrastructure question. It is a water-security question, a farmers’ livelihood question and a federal trust question.”
The Mekedatu project, proposed near Kanakapura in Karnataka, has been projected by Karnataka as a multipurpose reservoir meant to supply drinking water to Bengaluru and generate about 400 MW of power. Karnataka Deputy Chief Minister D.K. Shivakumar has maintained that the state will honour Tamil Nadu’s allocated Cauvery share, even as Karnataka prepares to push the project through the required channels.
Tamil Nadu, however, views the project through a different lens. The state fears that a new reservoir upstream could give Karnataka greater control over the timing and volume of Cauvery releases, especially during distress years. For the Cauvery delta, where agriculture depends heavily on predictable water flows, the issue is not only about annual allocation but also about seasonal reliability.
“A dam upstream can become a lever of control downstream. That is the central anxiety driving Tamil Nadu’s opposition.”
The legal background is complex. The Cauvery Water Disputes Tribunal delivered its final award on February 5, 2007, and the Supreme Court delivered its final judgment on February 16, 2018. Government records note that Karnataka is required to release 177.25 TMC of Cauvery water annually at Biligundulu on the interstate border with Tamil Nadu, under the Supreme Court’s 2018 order.
Vijay’s letter reportedly argues that entertaining Karnataka’s Mekedatu proposal without addressing Tamil Nadu’s objections would undermine the spirit of the 2018 judgment and the Cauvery framework. The Tamil Nadu government has also contended that the project would amount to a unilateral intervention in an already adjudicated river-sharing system.
The latest flashpoint follows the Supreme Court’s recent dismissal of Tamil Nadu’s review petition. Earlier, in November 2025, the court had described Tamil Nadu’s objections at the DPR stage as premature, noting that the project had not yet received approvals from bodies such as the Cauvery Water Management Authority and the Central Water Commission. Karnataka has interpreted the legal development as space to move the proposal forward, while Tamil Nadu has treated it as a reason to intensify political and administrative pressure on the Centre.
“The dispute now sits at the intersection of law, hydrology, federal politics and electoral emotion.”
For Karnataka, Mekedatu is framed as a long-pending urban water and power project, especially significant for Bengaluru’s growing demand. For Tamil Nadu, it is seen as a potential threat to downstream rights, delta agriculture and the delicate balance created by decades of tribunal proceedings and Supreme Court intervention.
The issue has also begun to widen politically within Tamil Nadu. MDMK leader Vaiko has announced a protest in Chennai on June 2 against the Mekedatu project, signalling that the matter could become a broader state-wide political campaign rather than remaining only an intergovernmental dispute.
Vijay’s appeal to Modi therefore carries both administrative and symbolic weight. Administratively, Tamil Nadu wants the Centre to stop the DPR from advancing through central agencies. Politically, the Chief Minister is attempting to position Tamil Nadu’s demand as a rights-based federal claim rather than a routine state objection.
The next phase will likely depend on how the Ministry of Jal Shakti, the Central Water Commission and the Cauvery Water Management Authority handle Karnataka’s proposal. Any movement toward approval could trigger another round of legal challenge and political mobilisation from Tamil Nadu. Any rejection or delay, on the other hand, would deepen Karnataka’s charge that a drinking-water and power project is being blocked.
For now, Mekedatu has once again become more than a dam proposal. It has become a test of how India manages interstate rivers when legal awards, urban demand, agricultural dependence and state pride collide.
