A panel of water experts from various prestigious academic institutions and State water board who gathered at IIT-Madras to mark World Water Day on Monday, observed that developmental activities were posing a major threat to the city’s water bodies. These unplanned activities have made the city prone to inundation and affected the groundwater recharging systems.

Ramalingam, director, Institute for Remote Sensing, Anna University pointed out that the Mass Rapid Transit System (MRTS) in Velachery ran right across the Pallikaranai swamp, hindering flow of water during heavy rains, thus causing inundation. The Velachery Main Road, Old Mahabalipuram Road and Thoraipakkam Road imposed severe restrictions on the movement of flood water, thus inundating the neighbouring areas.

“Previously the proposal was to have MRTS as an elevated system, but fixing pillars in the swampy land was impossible. The system in the current form has lead to complications,” Ramalingam said. He proposed that additional culverts be built along the course of MRTS to ease the condition.

Pollution of waterways and over-exploitation of groundwater resources have compounded the problems, said Sitharam Gurumurthi, Planning Commission member. He observed that 475 outlets of untreated sewage continue to pollute Cooum River even now when the State government has been trying to restore it. Metrowater till date has identified 57 of these outlets, which they hope to plug in a couple of years.

Sundaramurthy of the National Institute of Ocean Technology said that as the Chennai sewerage system was designed to dispose of its effluents in the water bodies, it was systemic problem. He also observed that the Centre’s sewage treatment manual framed in 1997 was outdated and the treatment standards have to be improved drastically.

Data provided by Institute for Remote Sensing showed that over 138 blocks of groundwater in the city was overexploited.