Mekedatu Reservoir: Karnataka Seeks Tamil Nadu's Cooperation and Prepares Forest Clearance Papers
The Karnataka government said it will go ahead with the Mekedatu balancing reservoir, a proposed dam on the Cauvery river at Mekedatu in Kanakapura taluk, close to the Tamil Nadu border.
Karnataka asked Tamil Nadu for its cooperation, saying the project mainly supplies drinking water to Bengaluru and will also help Tamil Nadu get its share of water on time. It invited Tamil Nadu to send a team to see the site.
This came after the Tamil Nadu government wrote to the Union government opposing the project. Tamil Nadu fears the dam will reduce the water that reaches its farmers.
Karnataka said the Supreme Court has upheld its right to develop the project, and that it will keep releasing 177.25 TMC (thousand million cubic feet) of Cauvery water a year to Tamil Nadu, as the Court ordered in 2018. In November 2025, the Supreme Court had refused to entertain Tamil Nadu's plea against the project, calling it "premature" because expert bodies have not yet examined the detailed project report.
About 5,400 hectares of forest land could go under water. Karnataka says it has identified other land for compensatory afforestation (growing new forest to make up for the lost forest), and is preparing its application for forest clearance from the Centre.
The project also includes a 400 MW hydropower (pumped-storage) part.
Mekedatu Balancing Reservoir-cum-Drinking Water Project
The Mekedatu project is a large dam and reservoir that Karnataka wants to build on the Cauvery river at Mekedatu, in Kanakapura taluk, very close to the Tamil Nadu border. Karnataka says the main purpose is drinking water for Bengaluru, plus some electricity. It calls it a "balancing reservoir" because it would store water and release it in a steady, planned way to Tamil Nadu downstream. Tamil Nadu opposes it because it fears an extra dam upstream will give Karnataka more control over water that Tamil Nadu depends on.
Karnataka is now pushing the project forward. It is asking for Tamil Nadu's cooperation and preparing its forest clearance application with compensatory afforestation land. The real tests ahead are the CWMA and CWC review of the DPR and the forest and environment approvals.
Cauvery Water Dispute and the Cauvery Water Management Authority
The Cauvery Water Dispute is a long fight over how to share the water of the Cauvery (Kaveri) river between Karnataka, Tamil Nadu, Kerala and Puducherry. Karnataka is upstream, where the river rises and gathers much of its water. Tamil Nadu is downstream and has the largest farming area that depends on the river. A tribunal gave its final award in 2007, and the Supreme Court changed it in 2018. Today, a central body makes sure each state gets its share.
Karnataka says Mekedatu will not reduce Tamil Nadu's share, because the 177.25 TMC release fixed by the Supreme Court still binds it. Tamil Nadu fears that a new upstream dam weakens its control over when and how much water arrives, especially in a dry year.
Compensatory Afforestation Fund (CAF) Act, 2016 and CAMPA
When a road, mine or dam needs forest land, the forest is cut down. Compensatory afforestation is the rule that the project must pay for a new forest to be grown elsewhere to make up for this loss. The Compensatory Afforestation Fund (CAF) Act, 2016 collects this money in special funds and decides how it is spent. The bodies that manage the money are called CAMPA (Compensatory Afforestation Fund Management and Planning Authority).
Because the Mekedatu reservoir would drown about 5,400 hectares of forest, Karnataka must identify land for compensatory afforestation and pay into the CAF before the Centre can give forest clearance. Its statement that land has been identified is a step towards that application.
- Mekedatu: on the Cauvery, Kanakapura taluk, Karnataka, near the Tamil Nadu border
- Planned storage: about 67 TMC; hydropower: 400 MW; 2019 DPR cost: about ₹9,000 crore
- Forest land likely to be submerged: about 5,400 hectares, including parts of the Cauvery Wildlife Sanctuary
- Supreme Court on 13 November 2025: Tamil Nadu's plea against DPR preparation was "premature"
- Supreme Court Cauvery judgment: 16 February 2018; Karnataka must release 177.25 TMC a year at Biligundlu (tribunal had fixed 192 TMC)
- Final shares: Tamil Nadu 404.25 TMC, Karnataka 284.75 TMC, Kerala 30 TMC, Puducherry 7 TMC
- CWMA and CWRC set up in 2018 under Section 6A of the Inter-State River Water Disputes Act, 1956
- CAF Act, 2016: 90% to State fund, 10% to National fund; in force from 30 September 2018