Tamil Nadu CM urges PM to block Mekedatu dam over legal violations
Tamil Nadu Chief Minister C. Joseph Vijay has written to Prime Minister Narendra Modi, seeking his intervention to prevent any statutory or administrative approval for the Mekedatu project unless it is proven consistent with the Cauvery Water Disputes Tribunal (CWDT) Award and the Supreme Court judgment.
In his letter dated July 28, 2026, Mr. Vijay also demanded the withdrawal of a reply given by Union Minister of State for Jal Shakti Raj Bhushan Choudhary in the Rajya Sabha on July 27. The Minister had stated that the Supreme Court judgment of February 16, 2018, does not explicitly require Karnataka to obtain Tamil Nadu's consent before constructing a structure across the Cauvery. Mr. Vijay called this reply “disappointing” and said it was made without considering settled legal principles on inter-state water disputes.
The Chief Minister cited the Supreme Court's ruling in the Alamatti case between Karnataka and Andhra Pradesh, where the Constitution Bench held that “the consent of the lower riparian State is absolutely necessary” for any construction. He also quoted the judgment to say that Karnataka cannot build without consent of all riparian states and approval of the central government.
Mr. Vijay noted that the Supreme Court affirmed Clause XVIII of the CWDT Award, which allows each state to regulate waters within its territory only in a manner not inconsistent with the Tribunal's order. Any project affecting the regulated flow regime must be scrutinised for consistency with the Award, he argued.
He pointed to the Tribunal's decision on Kerala's Pambar Hydro-electric Project, involving only 0.1 TMC of consumptive use, where it directed coordinated releases to protect downstream irrigation. This shows the Tribunal prioritised not just annual quantities but coordinated regulation affecting lower riparian interests, Mr. Vijay said.
The Chief Minister also invoked Clause XI of the Award, which prohibits upper riparian states from taking actions affecting scheduled deliveries to downstream states without mutual agreement and consultation with the regulatory authority. Clause XX similarly recognises that modifications to the Award require agreement among party states.
“Tamil Nadu is therefore of the considered opinion that the proposed Mekedatu Project cannot be evaluated merely as an engineering proposal. Its legal permissibility must first be examined in the context of the Final Award of the Cauvery Water Disputes Tribunal, the judgment of the Supreme Court on February 16, 2018, and the rights of the lower riparian States,” Mr. Vijay wrote.
He highlighted that the Detailed Project Report submitted by Karnataka in 2019 was returned by the Central Water Commission for revision to ensure compliance with the Tribunal Award and applicable guidelines, demonstrating that compliance remains an indispensable precondition.
The Chief Minister urged the Union government to fully protect the rights of lower riparian states regarding both quantum and regulated pattern of releases. He called for any future consideration of the project to be undertaken only after a comprehensive technical and legal examination taking into account all relevant factors.
