‘Do not clear Mekedatu project without states’ consent’: Vijay writes to PM Modi

Tamil Nadu Chief Minister C Joseph Vijay has urged Prime Minister Narendra Modi to ensure that Karnataka’s proposed Mekedatu dam project on the Cauvery does not receive any statutory or administrative approvals without the consent of the states sharing the river basin. He has also called for a halt to further technical or administrative action following reports of a site inspection by Union government officials.

In a letter to Modi on Saturday, Vijay expressed concern that the reported inspection could signal progress on the controversial project, which Tamil Nadu believes could jeopardise the water supply and livelihoods of farmers in the state.

The chief minister said farmers in the Cauvery Delta were already facing difficulties during the deficit water year 2026-27, alleging that Karnataka had failed to release Tamil Nadu’s due share of water even on a pro-rata basis.

“It is vital that the rights of lower riparian States regarding both the quantum and regulated pattern of monthly releases remain fully protected,” Vijay said.

He argued that considering or examining the Detailed Project Report (DPR) submitted by Karnataka, or undertaking unilateral technical evaluations and site inspections through central agencies at this stage, would be highly inappropriate.

Vijay flags impact of proposed reservoir on Tamil Nadu's water share

The Tamil Nadu chief minister objected to Karnataka’s proposal to construct a reservoir across the Cauvery, with a storage capacity of 67.16 thousand million cubic feet (TMC), just upstream of the inter-state border.

Vijay argued that the proposed reservoir would not only prevent flows due to Tamil Nadu but also adversely affect the monthly water deliveries to the state's Cauvery basin, as stipulated by the Supreme Court.

The Mekedatu project is envisaged as a multi-purpose balancing reservoir. Karnataka has said it would help meet Bengaluru’s drinking water requirements, regulate monthly water releases to Tamil Nadu at Biligundulu and generate 400 MW of hydroelectric power. However, the proposal has faced sustained opposition from Tamil Nadu over concerns about its impact on the state's share of Cauvery water.

Vijay said the reported site inspection had caused further anxiety among farmers, particularly amid frequent reports of Karnataka Chief Minister's meetings with officials of the Union ministries of Jal Shakti and Environment, Forest and Climate Change to seek clearance for the project's DPR without Tamil Nadu's concurrence.

“Earlier, a team of Government of India officers reportedly visited the proposed Mekedatu Dam site, as per the statements emanating from Karnataka. The anxious farmers of Tamil Nadu view the site visit as an indication of tacit movement on a project that would jeopardise their very livelihoods,” he said.

He urged Modi to defer any further administrative or technical action arising from the reported inspection and advise Karnataka against proceeding with the project without the consent of the co-basin states.

In his letter, Vijay also asked the Prime Minister to direct the Ministry of Jal Shakti and the Ministry of Environment, Forest and Climate Change to refrain from conducting site inspections or technical evaluations, or granting statutory and administrative clearances for the project without the consent of the lower riparian states.

“In view of the Supreme Court order dated February 16, 2018 (on Cauvery issue), the Ministry of Jal Shakti and the Ministry of Environment, Forest & Climate Change may be asked to refrain from undertaking any site inspections, technical evaluations, or granting any statutory, administrative clearances to the Mekedatu project without the consent of lower riparian States,” he said.

Tamil Nadu's legal and political opposition to Mekedatu

Vijay recalled that he had raised similar objections in a letter to Modi dated July 28, 2026. He had then opposed statutory or administrative approval for the project unless it was demonstrably consistent with the final award of the Cauvery Water Disputes Tribunal (CWDT) and the Supreme Court's judgment.

Tamil Nadu has also pursued legal and legislative measures against the proposal. On May 27, 2026, the state filed an Original Application before the Principal Bench of the National Green Tribunal, seeking, among other reliefs, to restrain the Union Ministry of Environment from granting any permission until the inter-state issues were resolved.

The Tamil Nadu Legislative Assembly subsequently passed a unanimous resolution on June 19, reiterating that the Ministry of Jal Shakti should not grant clearance to the Karnataka government, its instrumentalities or other related agencies for the project.

The state also filed a writ petition in the Supreme Court on August 3, seeking the withdrawal of guidelines issued by the Ministry of Jal Shakti in December 2025 for preparing DPRs for irrigation and multi-purpose project proposals specifically in the Cauvery basin.

Tamil Nadu's contention is that the Cauvery is a deficit basin, as held by the Tribunal in February 2007, and that the guidelines should therefore not be applied to the basin in a manner that could facilitate the proposed project. Vijay said the matter remained pending before the Supreme Court.

The latest appeal comes amid continuing disagreements between Karnataka and Tamil Nadu over the proposed reservoir and the sharing of Cauvery water. In July 2026, the Central Water Commission returned Karnataka's DPR for modifications, reportedly citing concerns over its conformity with the CWDT's final award and the Supreme Court's 2018 judgment. The commission asked the state to submit a revised proposal.