Tamil Nadu Announces ₹4,800-Crore Desalination Plant at Minjur

The Chennai Metropolitan Water Supply and Sewerage Board (CMWSSB) will set up a 400mld desalination plant at Minjur to address the increasing water demand across north Chennai and the surrounding suburbs. Chief Minister C Joseph Vijay announced the project in the state assembly on Wednesday as part of a series of municipal water initiatives.

The new facility at Minjur carries an estimated cost of ₹4,800 crore. It will be supported by a ₹500-crore pipeline and pumping station project in Avadi to strengthen drinking water distribution to neighbouring localities. At present, an existing 100mld desalination plant in the area has remained non-operational due to ongoing court litigation, leaving residents in neighbourhoods such as Tiruvottiyur, Manali, and Madhavaram dependent on private water tankers and borewells.

According to officials, the upcoming project will function as an expansion of the existing facility near Minjur. The existing plant will be scaled up to 100mld, while the new 400mld unit will supply the north Chennai and Avadi belts. In the event of an emergency, desalinated water can also be redirected to southern areas through an upcoming ring main pipeline. The water board also plans to expedite the proposed Perur desalination plant, which is slated to serve the OMR, ECR, and Tambaram regions.

Alongside the desalination project, CMWSSB will execute drinking water and sewerage infrastructure works valued at ₹236 crore across Perambur, Kolathur, Villivakkam, Egmore, and other parts of the city. The initiative involves replacing aged pipelines and building new pumping stations to enhance last-mile delivery.

However, the announcement has drawn scrutiny from water management experts who advocate for sustainable alternatives. J Saravanan, hydrologist and team lead of the Chennai Basin Water Security Plan, urged authorities to prioritise local water bodies rather than expanding desalination capacity.

Saravanan pointed out that his team had proposed measures to desilt and expand the holding capacity of 4,000 water bodies across Chennai, Tiruvallur, Kancheepuram, and Chengalpattu districts. He noted that capturing urban rainwater runoff, linking larger water bodies into bigger reservoirs, and recycling the 1,200mld of sewage generated by the city could deliver integrated water security, flood management, and climate resilience at half the cost of the proposed 400mld desalination plant.