Desalination projects get a boost

Expert committee to inspect proposed site for one of the plants at Perur, along East Coast Road

Desalination projects in the city, which have been delayed for various reasons, may soon be back on track. An expert appraisal committee from the Centre is expected to inspect the proposed site for a 400 mld desalination plant at Perur along East Coast Road in February to provide environmental clearance for the project.

The Environment Assessment Committee (EAC) of the Ministry of Environment, Forest and Climate Change had recently deferred the proposal and also questioned the setting up of two plants of different treatment capacities within a short distance of each other.
Officials of the Chennai Metrowater said a fresh proposal addressing the queries raised by the EAC is also being prepared. The water agency is negotiating with the Japan International Cooperation Agency to fund the plant at Perur.
​
Metrowater is confident that the project to build a 150 mld desalination plant at the existing site in Nemmeli can be started this year as environmental clearance has been obtained. The Nemmeli plant will come up with the assistance of KfW, a German funding agency. While the technical evaluation of the bids for the project is in progress, the water agency is mulling the use of pipe jacking technology to minimise shoreline erosion.

Pipe jacking technology involves the use of specialised equipment to push lengths of pipeline into the seabed through a shore pit drilled for a diameter of up to 1 m. This is expected to help lay pipelines for drawal of sea water and disposal of brine without much disturbance to the shoreline. The dredging of the seabed for a 100 MLD plant in Nemmeli had caused much damage to the shoreline.

Increase in supply

Meanwhile, the Water Resources Department is also expecting an increase in the release of Krishna water in a fortnight. In the past 12 days, Poondi reservoir has realised nearly 180 million cubic feet. On Friday, nearly 275 cusecs (one cusec is equal to 28.3 litres of water per second) was received at Uthukottai in Tiruvallur district, which is the entry point of the Kandaleru Poondi canal in Tamil Nadu. Once the drawal for irrigation comes down in Andhra Pradesh, reservoirs in Chennai may get more Krishna water. Tamil Nadu has to be provided 4,000 mcft. of water between January and April as per the agreement between the States.