Lakes may be tapped for city’s needs

In an effort to identify new sources of water to supply the growing metropolis, Chennai Metrowater has started a feasibility study to assess the potential of nine waterbodies and six abandoned quarries in the city’s periphery as drinking water sources.

Special team set up

A special team has been constituted to explore new sources to augment the city’s water supply. The team has started collecting samples for testing the quality of water on 45 parameters.

The water sources identified include lakes in Manimangalam, Ayanambakkam, Sriperumbudur, Thaiyur, Korattur, Mambakkam, Arasankazhani and Thenneri. Water samples in abandoned quarries in Nallambakkam, Pammal, Pallavaram and Erumaiyur would also be tested to ascertain whether they are suitable for drinking, said a press release.

Metrowater is carrying out the study along with the Public Works Department, Anna University and IIT Madras.

Porur lake was the first to be chosen for tapping water to cater to Chennai’s water requirements in 2017. A modular water treatment plant with a capacity to treat four million litres a day (mld) was set up to treat raw water and transport it to the existing network, the release added. The water agency had recently conducted a similar survey at Retteri lake to assess its quality.

Metrowater officials said a proposal has been submitted to the State government to set up a treatment plant of 10 MLD capacity at a cost of nearly ₹8.8 crore to treat and transport water to the network at Kolathur. “We found that the lake has a capacity to store nearly 110 million cubic feet of water. Extraction would improve the quality and reduce sediment deposits,” said an official.

The aim is to decentralise treatment and transportation of water and use local sources. “We may also recommend use of some sources to the other local bodies in the Chennai metropolitan area that are beyond the Metrowater supply limits,” the official said.

Besides studying the lakes for their available storage capacity and availability of land for onsite facilities, various aspects such as pollution due to release of domestic sewage and the feasibility of laying pipelines to connect to the existing network would also be looked at.