MW to use treated water to keep lakes alive even during summer

According to a Metro Water official, the move was mooted to recharge groundwater table and also to find a solution to the city’s sewage problem. “As all the lakes selected for the project are located inside the city or just outside, they will provide succour during the summer season when the residents tap more groundwater,” the official said.

Narayanapuram lake near Pallikaranai, Nanmangalam lake, Kovilambakkam lake, Keelkattalai lake, Perungudi lake and Porur lake have been selected for the project. Works on setting up sewage treatment plants have already started near Perungudi and Porur lakes on pilot basis. The lakes will have tertiary treatment reverse osmosis (TTRO) sewagetreatment plants.

“Once the works are completed at Porur and Perungudi, tertiary treated water will be let into them. The pilot project is being carried out with our own funds. We have sought funds from World Bank for the other four lakes,” theofficial added.

The water manager has estimated Rs 1,800 crore for these four lakes and is expecting the funds from the funding agency, which has already agreed to give around Rs 50,000 crore for Chennai’s infrastructure projects.

However, residents pointed out that the Metro Water has failed to arrest untreated sewage entering the Porur lake. “We have to seal two sewage inlets that are draining into the lake once the treatment plant near the lake starts operation,” another official said.

When asked whether the treated sewage water would pollute the lakes, the official explained that the sewage water would be treated using TTRO technology, which renders potable water. The Metro Water had commissioned TTRO plants in Koyambedu and Kodungaiyur to supply treated water to industries around the city.

Meanwhile, the Metro Water has drawn up plans to use water from Rettai Eri, Ayanambakkam lake and Perumbakkam lake to ensure decentralised water supply during the coming summer.