Mekedatu: Centre cites SC order to say Karnataka need not take consent of riparian States to build structure across Cauvery
The Union Government stated in Parliament that Karnataka is not legally required to obtain the consent of Tamil Nadu, Kerala, or Puducherry before constructing a structure across the Cauvery river for the proposed Mekedatu balancing reservoir-cum-drinking water project.
The clarification cites the Supreme Court's February 2018 final verdict on the Cauvery water-sharing dispute, which the government states does not prescribe any requirement for Karnataka to seek approval from co-riparian states before building such a structure.
Karnataka has maintained that the project, proposed at Kanakapura taluk in Bengaluru South district, will not affect the stipulated quantum of Cauvery water it is required to release downstream to Tamil Nadu.
Tamil Nadu continues to oppose the project, arguing that as the lower riparian state its consent is necessary given the potential impact on downstream water flow.
Article 262 and the Inter-State River Water Disputes Act, 1956
Article 262 of the Constitution empowers Parliament to legislate on the adjudication of disputes relating to waters of inter-state rivers or river valleys, and permits Parliament to bar the jurisdiction of the Supreme Court and other courts over such disputes. Parliament exercised this power by enacting the Inter-State River Water Disputes (ISRWD) Act, 1956, which allows the Centre to constitute an ad hoc tribunal when a water dispute cannot be resolved through negotiation between states.
Key Details
- The ISRWD Act, 1956 was enacted under the residuary legislative competence given by Article 262; river water disputes fall under Entry 56 of the Union List and Entry 17 of the State List (subject to Union control under Entry 56).
- The Supreme Court's 2018 Cauvery judgment held that Section 11 of the ISRWD Act, which seeks to bar the jurisdiction of courts other than the Supreme Court, cannot oust the Supreme Court's own appellate jurisdiction under Article 136 (Special Leave Petition) over a tribunal's award.
- Other active inter-state river tribunals include the Krishna, Godavari, Narmada, Ravi-Beas, and Mahadayi tribunals.
The Centre's position that no riparian consent is required for Mekedatu is grounded in reading the 2018 Supreme Court verdict as the final word on Cauvery water apportionment, with no additional procedural veto created for co-riparian states over infrastructure built within an allocated share.
The 2018 Supreme Court Cauvery Verdict
In February 2018, a Supreme Court bench delivered its final verdict in the decades-long Cauvery water dispute, modifying the 2007 award of the Cauvery Water Disputes Tribunal. The Court held that a river is a national asset and no single state can claim ownership over its waters.
Key Details
- The Court increased Karnataka's allocation by 14.75 thousand million cubic feet (TMC ft) over the Tribunal's 2007 award, of which about 4.75 TMC ft was earmarked specifically for the drinking and domestic water needs of Bengaluru and surrounding areas.
- Tamil Nadu's allocation was correspondingly reduced, from 192 TMC ft (under the 2007 award) to 177.25 TMC ft, while the overall basin yield used for apportionment remained at 740 TMC ft.
- The judgment directed the Centre to frame a scheme for implementation, leading to the constitution of the Cauvery Water Management Authority.
The Centre's reply leans on this verdict's silence on any riparian-consent requirement to argue that Karnataka's Mekedatu proposal is a matter of using its own allocated share efficiently, not a fresh apportionment question requiring Tamil Nadu's approval.
Cauvery Water Management Authority (CWMA) and Cauvery Water Regulation Committee (CWRC)
Following the 2018 Supreme Court directions, the Central Government notified the Cauvery Water Management Scheme in June 2018, setting up the CWMA and CWRC under Section 6A of the Inter-State River Water Disputes Act, 1956.
Key Details
- The CWMA is a statutory, quasi-judicial authority responsible for the regulation of storage, apportionment, and release of Cauvery waters among Karnataka, Tamil Nadu, Kerala, and Puducherry.
- The CWRC handles day-to-day operational regulation and monitoring of reservoir levels and water release schedules on behalf of the CWMA.
- Any new storage structure on the Cauvery basin, such as the proposed Mekedatu reservoir, would ultimately be regulated for water release through the CWMA/CWRC framework rather than through bilateral state consent.
Even without a riparian-consent requirement at the approval stage, the CWMA/CWRC mechanism would govern how Cauvery water is actually released once any Mekedatu structure is built, providing the institutional channel through which Tamil Nadu's downstream entitlement is expected to be protected.
- Supreme Court's final Cauvery verdict: February 2018.
- Karnataka's enhanced allocation over the 2007 Tribunal award: 14.75 TMC ft (of which ~4.75 TMC ft for Bengaluru's drinking water needs).
- Tamil Nadu's revised allocation: 177.25 TMC ft (down from 192 TMC ft under the 2007 award).
- CWMA and CWRC notified: June 2018, under Section 6A of the ISRWD Act, 1956.
- Mekedatu project location: Kanakapura taluk, Bengaluru South district, on the Cauvery river.
- Reported project capacity and cost figures vary across official statements (cited in the range of roughly 48–67 TMC ft capacity and Rs 6,000–9,000 crore cost) [Unverified — exact current DPR figures].