Desilting work expected to start in April and be completed by next year

Three waterbodies in the city fringeswill soon get a new lease of life as the water Resources Department has floated tenders to increase their storage capacity .

The tanks at Porur, Nemam near Thirumazhisai and Ayanambakkam would be rejuvenated with additional storage capacity to ensure availability of more resources and meet the growing demand of the city.

WRD officials said the tanks would be deepened by at least one metre at a cost of Rs.130 crore. Spread over 200 acre, the Porur tank has been subjected to misuse owing to lack of attention for many years. Besides increasing its storage capacity from 46 million cubic feet (mcft) to 70 mcft, the WRD would carry out works to strengthen the bund, repair surplus weir and plugging of sewage inlets. The Thanthikal channel, which links Porur tanks to Chembarampakkam reservoir, would also be improved.

The improvement works to Ayanambakkam tank would include reconstruction of weir and regulators. The supply channel from Paruthipattu anicut across Cooum river to the tank would also be improved. A surplus course from the Nemam tank to Chembarampakkam reservoir would be formed for a distance of 1.6 km to divert water for city drinking water supply.

A feeder canal to Nemam tank would also be created to transmit Krishna water from Poondi reservoir.

The project would enhance the storage capacity by about 400 mcft in these tanks. This is equivalent to two weeks of drinking water supply to the city at the rate of 800 million litres a day, the officials said.

The soil excavated from the tanks would be provided for other government projects. Nearly 20 per cent of the project cost is expected to be recovered through sales of about 50 lakh cubic metre of soil excavated from the tanks. Work to desilt the tanks is expected to start in April and be completed by next year. Chennai Metrowater has also been asked to create pipeline network to draw water from the tanks for city supply, an official added.