T.N. CM writes to PM seeking intervention in dam row

What happened

Tamil Nadu Chief Minister C. Joseph Vijay wrote to Prime Minister Narendra Modi seeking two related interventions connected to the proposed Mekedatu project on the Cauvery. Vijay asked the Centre not to grant statutory or administrative approvals for the Mekedatu project unless the proposal is shown to be consistent with the Cauvery Water Disputes Tribunal award and the Supreme Court judgment in the Cauvery dispute.Vijay asked for withdrawal of a reply made by Union Minister of State for Jal Shakti, Raj Bhushan Choudhary, in the Rajya Sabha on July 27.

Background: what the July 27 Rajya Sabha reply said and what Vijay disputed

The July 27 Rajya Sabha reply, as described by Vijay, stated that the Supreme Court’s February 16, 2018 judgment did not require Karnataka to obtain consent from lower riparian states before building structures across the Cauvery. Vijay disputed this interpretation and argued that Supreme Court Constitution Bench reasoning in the Alamatti case (Karnataka vs Andhra Pradesh) makes lower riparian consent “absolutely necessary” for the relevant construction height and conditions.

What Vijay claimed about Supreme Court rulings and the tribunal’s award

Vijay’s letter linked the Mekedatu approvals dispute to two legal strands: consent/conditions for construction across a river, and compliance with the tribunal’s regulated flow framework. Alamatti case (Constitution Bench reasoning): Vijay quoted a principle he said comes from the ruling that Karnataka cannot be allowed to construct “up to a height” without consent of all other riparian states and without Central Government approval.Cauvery Water Disputes Tribunal award and Clause XVIII: Vijay argued that the Supreme Court in the February 16, 2018 judgment affirmed Clause XVIII, which preserves each state’s power to regulate water within its territory, but only in a way consistent with the tribunal’s order.Consistency with the “regulated flow regime”: Vijay argued that any Mekedatu project that could affect the regulated flow regime created under the tribunal award requires scrutiny for consistency with the award.