At present, TN accounts for 24% of the total desalinated water capacity in India, second only to Gujarat. Experts meanwhile describe desalination as a “last option”.S Janakarajan, professor at Madras Institute of Development Studies, says that seawater desalination was conceived for rich, rain-starved countries like those in West Asia. “Chennai’s average annual rainfall is well over 1,200 mm. It should ideally be the last resort which, in this case, is not,” Janakarajan said. With scant supply , water distribution is charted out daily by the CMWSSB.”Our planning [daily distribution] hinges on how much water the desalination plants supply ,” Arun Roy , managing director of CMWSSB, said.

On average, the two plants churn out around 180 mld of the 470 mld CMWSSB now supplies, against Chennai’s demand of 1,300-1,400 mld.The plant in Minjur caters to industries and a few localities in north Chennai, while the Nemmeli plant caters to nearly 13-15 lakh residents in south Chennai, which is also house to the city’s IT hub.

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