What is the dispute over the Mekedatu dam project?

Karnataka plans to build a ₹9,000 crore buffer tank at Mekedat, about 100 km from Bengaluru, to hold 67.16 million cubic feet (TMC) of water. File. | Photo credit: Sudhakara Jain

Story so far: On November 18, the Karnataka government decided to submit a ‘revised’ detailed project report (DPR) to the Center on the Mekedatu buffer tank across the inter-state Cauvery river. Five days earlier, the Supreme Court had termed Tamil Nadu’s plea challenging the project proposed by Karnataka as “premature”. With this development, the decks were cleared for the Cauvery Water Management Authority (CWMA) and the Central Water Commission (CWC) to examine the proposal of the upper riparian state.

How did Tamil Nadu respond?

While the opposition in Tamil Nadu blamed the Dravida Munnetra Kazhagam government for the Supreme Court’s decision, the lower coastal state’s water resources minister Durai Murugan refuted reports that the court had cleared the dam, saying his government would resist any attempt by Karnataka to go ahead with the project. Karnataka Deputy Chief Minister DK Shivakumar termed the court’s order as “justice to the state”.

What are the main features of the project?

Karnataka plans to build a ₹9,000 crore buffer tank at Mekedat, about 100 km from Bengaluru, to hold 67.16 million cubic feet (TMC) of water. It will also have a 400 MW hydro component. The project will flood around 4,996 hectares of land, including about 4,800 hectares of forest land and wildlife land. Karnataka is expected to help tap the additional 4.75 TMC of water allocated by the Supreme Court in its February 2018 judgment in the Cauvery dispute to meet Bengaluru’s growing drinking water needs. Although the project was considered as far back as 1948, it gained momentum only in recent years, when the upper coastal state’s capital suffered from severe water shortages in the summer.

Why is the project controversial?

The history of the Cauvery sharing dispute has led to a serious trust deficit between Tamil Nadu and Karanataka. The complaint of the downstream state against the upstream state is gaining intensity because the results of this state in terms of water release during the first four months of the water year (June to May) are far from satisfactory. This is why Tamil Nadu fears that the project, if it comes to fruition, could lead to Karnataka over-storing water and releasing it at will. But Mr Shivakumar says the project, to be implemented in Karnataka and from the state’s own resources, would help his state supply water to Tamil Nadu as per the final order of the Cauvery Water Disputes Tribunal “even during bad monsoon years”.

How important is the project?

According to information provided by Karnataka Chief Minister Siddaramaiah in March 2024 during the acute water shortage in Bengaluru, the city required 2,600 million liters per day (MLD) while the available quantity was 2,100 MLD, leaving a shortfall of 500 MLD. The Cauvery River meets the demand of 1,450 MLD of which 650 MLD comes from groundwater. Bengaluru’s population, now 13 million, is expected to reach the 20 million mark in six years; then the city will need 4000 MLD. It was against this background that Mr. Shivakumar justified the early implementation of the Mekedatu project. However, the Supreme Court awarded Bengaluru only 4.75 TMC per annum (equivalent to about 370 MLD).

However, there are other ways to solve the water problem. TV Ramachandra, a senior academician at the Center for Environmental Sciences, Indian Institute of Science, Bengaluru, says the city receives 700-850 mm of rainfall annually, which in turn yields about 15 TMC (around 1,160 MLD), apart from the reuse of treated sewage, which is likely to provide about 16.24 TMC annually (MLD11).

How does the Center deal with the problem?

In January 2019, Karnataka submitted the DPR to the CWC, which in turn forwarded it to the CWMA. In July 2019, when the ministry’s expert review committee sought approval from the Union Ministry of Environment, Forests and Climate Change for the tender to carry out an environmental impact assessment study, it concluded that an “amicable solution” was needed between the two states in view of the inter-state issues. On 1 February 2024, the CWMA decided to return the project back to the CWC after “detailed consideration”.

Now the authority and CWC can provide both the states a platform to discuss, if possible, understanding the project.

Published – 23 Nov 2025 01:36 IST