Work on a pilot project to sink recharge wells in five locations across Chennai will begin soon. The project aims to demonstrate the use of recharge wells in shallow aquifer management and regulate urban flooding.
The project will be jointly executed by the Greater Chennai Corporation and Rain Centre, a city-based voluntary organisation.
Rain Centre has been identified to design the project and provide technical guidance to the civic body as part of a pilot study on shallow aquifer management in selected AMRUT cities carried out by the Union Ministry of Housing and Urban Affairs.
The recharge wells, which would be 20-feet deep and 5 feet in diameter, would be sunk in Madras University, Guindy; Gandhi Mandapam; Ripon Building; Chennai School, Saidapet and GCC zone 9 office near Valluvar Kottam.
Pointing out that the shallow aquifer available a few feet beneath ground is mostly ignored, Sekhar Raghavan, Director, Rain Centre, said the pilot project would demonstrate the need to replenish shallow aquifer by harnessing rainwater. Groundwater in shallow aquifer must be used more than deep aquifer that is difficult to replenish.
“We had signed a memorandum of understanding with the National Institute of Urban Affairs, New Delhi, to promote shallow aquifer recharge and use and sensitise various stakeholders on managing the shallow aquifer,” he said. A workshop would soon be organised for architects and builders on the potential of shallow aquifer in meeting water needs at micro and macro level.
Recalling urban floods in 2021 and 2023, he said Chennai was flooded as shallow groundwater aquifer had reached its saturation then. Drawing groundwater from open wells, which can be sunk even in places with space constraint, would be a solution to reduce localised flooding.
Instead of borewells, tube wells of 20-25 feet depth could also be sunk to tap shallow aquifer. It would be a solution to manage water resources in summer and floods, he said.
The recharge wells to be constructed would also have water level sensors to measure groundwater table.
Officials of the Greater Chennai Corporation said the locations were chosen for the pilot study to harness rooftop and driveway runoff and minimise water stagnation in these premises. The success model in these locations would be replicated in other vulnerable places, particularly those without stormwater drains, to recharge groundwater and reduce waterlogging.
A recharge well would have an impact on groundwater table and quality in a radius of a minimum 500 metre, officials added.
