CHENNAI: In a bid to save the depleting groundwater table in Chennai, the State government is mulling to ban the extraction of groundwater for construction purposes. Instead of groundwater, the Chennai Metropolitan Water Supply and Sewerage Board (Metro Water) would supply recycled water to the builders.
According to sources, the water manager is in talks at the government level to issue a government order (GO) as soon as possible. "The GO, if passed, will ban extraction of groundwater for any other purpose except for drinking purposes. It is also illegal to draw groundwater for construction," a source said.
Presently, Metro Water runs two wastewater plants (Tertiary Treatment Reverse Osmosis - TTRO) with a capacity of 45 MLD each at Kodungaiyur and Koyambedu. Even though the tertiary treated water, which is of potable quality, is being supplied to industries in and around Manali and Sriperumbudur, the demand for treated water is lower than the production.
Metro Water supplies around 30 million litres per day (MLD) to Manali industries and around 25 MLD to Sriperumbudur industries. "However, the builders are not keen on buying treated water owing to the transportation cost and they draw groundwater at the construction site, " the source added.
Saying that the actual combined production capacity of the two TTRO plants is 110 MLD, the source assured that sufficient water can be supplied to the construction industry if there is demand. Moreover, the water manager will also supply drinking water for construction after obtaining permission from the government. Presently, Metro Water cannot provide drinking water for any other purpose. Constructing one square foot requires around 100 litres of water for curing concrete and other purposes.
Recently, representatives of the Confederation of Real Estate Developers' Associations of India (CREDAI) visited the Koyambedu TTRO plant to check whether the treated water is pure enough to use in construction.
S Sridharan, CREDAI National's vice-president, said water reuse for construction is a good thing. "If the water is of good quality, there is no issue using it," he said.
Metro Water also supplies secondary treated water to Greater Chennai Corporation for watering parks and centre medians.