Karnataka is planning to build a ₹9,000-crore balancing reservoir at Mekedatu, about 100 km from Bengaluru, for impounding 67.16 thousand million cubic ft (TMC) of water. File.
| Photo Credit: Sudhakara Jain
The story so far: On November 18, the Karnataka government decided that it would submit a “revised” Detailed Project Report (DPR) to the Centre on the Mekedatu balancing reservoir across the inter-State river Cauvery. Five days earlier, the Supreme Court termed as “premature” the application of Tamil Nadu challenging the project proposed by Karnataka. With this development, the decks have been cleared for the Cauvery Water Management Authority (CWMA) and the Central Water Commission (CWC) to examine the upper riparian State’s proposal.
How has Tamil Nadu reacted?
While the Opposition in Tamil Nadu has blamed the Dravida Munnetra Kazhagam government for the top Court’s ruling, the lower riparian State’s Water Resources Minister Durai Murugan rebutted reports of the Court having permitted the construction of the dam and asserted that his government would resist Karnataka’s every attempt to proceed with the project. Karnataka Deputy Chief Minister D.K. Shivakumar called the Court’s order “justice to the State.”
What are the main features of the project?
Karnataka is planning to build a ₹9,000-crore balancing reservoir at Mekedatu, about 100 km from Bengaluru, for impounding 67.16 thousand million cubic ft (TMC) of water. It will have a 400 MW hydro power component too. The project will submerge around 4,996 hectares of land, including about 4,800 hectares of forest and wildlife land. It is expected to help Karnataka utilise an additional 4.75 TMC of water allotted by the Supreme Court, in its judgment in February 2018 on the Cauvery dispute, to meet the growing drinking water needs of Bengaluru. Though the project was mooted as early as 1948, it acquired momentum only in recent years with the capital city of the upper riparian State experiencing severe water shortages in the summer.
Why is the project controversial?
The history of the dispute over the sharing of the Cauvery has led to a serious trust deficit between Tamil Nadu and Karanataka. The lower riparian State’s grievance against the upper riparian State acquires more intensity as the track record of the latter in releasing water during the first four months of the water year (June to May) is viewed as being far from satisfactory. This is why Tamil Nadu is apprehensive that the project, when fructified, may lead to Karnataka storing water excessively and releasing it at its will. However, Mr. Shivakumar contends that the project, to be carried out within Karnataka and out of the State’s own resources, would help his State supply water to Tamil Nadu as per the Cauvery Water Disputes Tribunal’s final order “even during poor rain years.”
How important is the project?
As per information furnished by Karnataka Chief Minister Siddaramaiah in March 2024 during Bengaluru’s acute water shortage, the city requires 2,600 million litres a day (MLD) while the available quantum was 2,100 MLD, leaving a shortfall of 500 MLD. The Cauvery river meets the demand for 1,450 MLD with 650 MLD sourced from groundwater. The population of Bengaluru, which is now 13 million, is expected to touch the 20-million mark in six years; then the city will need 4,000 MLD. It is against this backdrop that Mr. Shivakumar justified the early implementation of the Mekedatu project. But, the top Court awarded only 4.75 TMC per year to Bengaluru (equivalent to about 370 MLD).
However, there are other ways to tackle the water problem. T.V. Ramachandra, veteran academician in the Centre for Ecological Sciences, Indian Institute of Science, Bengaluru, has been saying that the city gets annual rainfall of 700-850 mm, which, in turn, yields about 15 TMC (around 1,160 MLD), apart from the reuse of treated wastewater likely to provide about 16 TMC annually (1,240 MLD).
How does the Centre view the issue?
In January 2019, Karnataka submitted the DPR to the CWC, which, in turn, had forwarded it to the CWMA. When it had sought approval from the Union Ministry of Environment, Forest and Climate Change on the terms of reference to conduct the Environmental Impact Assessment study, the Ministry’s Expert Appraisal Committee, in July 2019, concluded that in view of inter-State issues, an “amicable solution” is needed between the two States. On February 1, 2024, the CWMA, after a “detailed deliberation” decided to refer the project back to the CWC.
Now, the Authority and the CWC can provide a platform to the two States for a discussion, if possible, an understanding, on the project.
Published – November 23, 2025 01:36 am IST
