Supreme Court rejects premature challenge to Mekedatu DPR and defers to expert bodies for water-management decisions

A bench of Chief Justice B.R. Gavai and Justices K. Vinod Chandran and Vipul M. Pancholi heard applications and ancillary petitions arising from the long‑running Cauvery water disputes, including a plea by the State of Tamil Nadu seeking to stay the Central Water Commission’s (CWC) November 22, 2018 permission to Karnataka to prepare a Detailed Project Report (DPR) for the proposed Mekedatu Balancing Reservoir cum Drinking Water Project.

The Court held that the challenge was premature and declined to interfere with the CWC’s limited permission to prepare a DPR, observing that the CWC had imposed conditions and that prior approval of the Cauvery Water Management Authority (CWMA) and consideration by the Cauvery Water Regulatory Committee (CWRC) would be prerequisites before any final decision. The Court noted that expert bodies constituted by the Union were best placed to examine technical and operational aspects and that judicial intervention should be avoided at this stage. The Court, in its reasoning, observed: “It cannot be disputed that every State is free to utilise water allotted to its quota in the manner it finds to be in the best interest of the State. No other State has a right to interfere with the decision regarding the management and use of water allotted to a particular State unless by such act the water allotted to that State is reduced. As already discussed hereinabove, the CWMA and CWRC are the body of experts which will have to ensure that the water allotted to the State of Tamil Nadu reaches as per the Award of the CWDT, as modified by this Court, at the measuring point at Biligundulu.” The Court further recorded that failure to comply with directions of the CWMA could attract contempt proceedings.

Background The dispute traced to this Court’s final judgment of February 16, 2018 in the long‑running Cauvery water litigation, after which the Union notified the Cauvery Water Management Scheme creating the CWMA and CWRC for implementation. Karnataka applied to the CWC for permission to prepare a DPR for the Mekedatu project. A CWC Screening Committee meeting of October 24, 2018—comprising technical officers of CWC and the Central Electricity Authority (CEA)—found that subject to certain conditions the DPR could proceed. Tamil Nadu objected to the Screening Committee’s recommendations and urged that a dam at Mekedatu would amount to modification of the CWDT award as affirmed by this Court and would impair Tamil Nadu’s entitlement to “uncontrolled flow of water”.

The CWC, by its November 22, 2018 letter, permitted preparation of the DPR but expressly required Karnataka to consider Tamil Nadu’s objections and to consult the CEA and concerned CWC directorates. The CWC also stated that acceptance of the DPR by the CWMA would be a pre‑requisite for further consideration. Tamil Nadu returned to this Court by way of miscellaneous applications and a contempt petition; the Court recalled its earlier interim orders in 2023 and emphasised that it “do[es] not possess expertise in the said matter,” directing reliance on the expert bodies and their established mechanisms.

After hearing senior counsel for the States and the Union Territory of Puducherry, the Court held the petitions premature because the CWC’s action was limited to permitting DPR preparation with conditions and because any final decision would follow technical review and CWMA/CWRC approval. The Court disposed of the miscellaneous applications and contempt petition, declined to grant the reliefs sought by Tamil Nadu, and observed that if the DPR were approved, parties would remain “at liberty to take such steps as are permissible in law.” The Court also reiterated that questions of compliance with water release directions remained subject to oversight by CWMA/CWRC and measurement by CWC at Biligundulu; non‑compliance could invite contempt.

Case Details: Case No.: 2025 INSC 1343; Civil Appeal No. 2453 of 2007 (and connected miscellaneous applications) Case Title: The State of Karnataka by its Chief Secretary v. State of Tamil Nadu by its Chief Secretary & Others Appearances: For the Petitioner(s): Shri Shyam Divan, Senior Counsel; Shri Shashi Kiran Shetty, Advocate General (Karnataka) For the Respondent(s): Shri Mukul Rohtagi, Senior Counsel (for Tamil Nadu); Shri Aravindh Selvaraj, Counsel (for Union Territory of Puducherry)