Despite being a non-starter, the Mekedatu dam project across the Cauvery, being pursued by Karnataka since the early 1960s, remains a source of friction between the upper riparian State and Tamil Nadu.
At different points of time, the project has made the headlines only to get relegated to the background. This time, the closure of the suomotu proceedings, by the Principal Bench of the National Green Tribunal, on the alleged violation of environmental norms in the implementation has brought Mekedatu to the fore.
The project, originally mooted in 1948, came up for investigation after the States were re-organised in 1956. It was talked about prominently in the early 1960s. Around the same time, Tamil Nadu came up with the Hogenakkal project. Subsequently, Mekedatu was almost forgotten after the two States were locked in an acrimonious dispute on the basic issue of sharing the Cauvery water. It came back to life when the two States held five rounds of negotiations in 1996-97.
A few years later, the Centre evinced interest in reviving it and formulated a package of four projects — two each in Karnataka and Tamil Nadu encompassing Mekedatu and Hogenakkal. So long as the Centre was in the picture, Tamil Nadu participated in the discussions that went on intermittently for 10 years because it favoured the National Hydro Power Corporation (NHPC) or any other Central government agency executing the projects without harming the orders of the Cauvery Water Disputes Tribunal (CWDT) on water-sharing. Karnataka, which also took part in the talks held by the Centre, has for the last seven-eight years reverted to its earlier stand of implementing Mekedatu on its own.
Taking note of the deliberations between the States and the NHPC, the CWDT, in its final order of February 2007, emphasised that “whenever any such hydro-power project is constructed and Cauvery waters are stored in the reservoir, the pattern of downstream releases should be consistent with our order so that the irrigation requirements are not jeopardised”. In February 2018, the Supreme Court, while modifying the CWDT’s final order, did not disturb this position.
In June 2019, Karnataka prepared a “pre-feasibility report”, seeking to meet three broad objectives. The proposed “balancing reservoir” at Mekedatu (between Krishnaraja Sagar-Kabini and Mettur), with a capacity of 67 thousand million cubic feet (tmc ft), will regulate the release of the required quantum to Tamil Nadu on a monthly basis, as stipulated by the CWDT and the Supreme Court. It will also address the drinking water needs of the Bengaluru Metropolitan Region and the adjoining areas, besides generating 400 megawatt of electricity.
Tamil Nadu’s concerns are essentially over the basic features, says an official. As the site will be downstream of Krishnaraja Sagar and Kabini, Tamil Nadu will be deprived of the benefits of rainfall in the intermediate catchments of the two dams in Karnataka and the Mettur dam. In fact, in the last 25 years or so, water realisation in October and November was primarily owing to this factor rather than Karnataka releasing water on its own. Tamil Nadu has received around 80 tmc ft annually, thanks to the run-off from the intermediate catchments.
The official says the State’s suit, filed in 2018, is pending in the Supreme Court. For all these reasons, the Expert Appraisal Committee for River Valley and Hydroelectric Projects of the Union Ministry of Environment, Forest and Climate Change said the proposal for environmental clearance could be reconsidered after the States reached an “amicable solution”.