New Delhi, June 05: Over-exploitation of groundwater coupled with the disposal of a large quantity of untreated and partially treated waste water in the city`s water bodies are taking a toll on the quality of drinking water, experts said here today. "In order to feed the growing population, water resources are being over-exploited which is a major cause for the deterioration of groundwater quality," additional director and incharge of Central Pollution Control Board Dr R C Trivedi said at a conference on `World Environment Day`.

Unplanned urbanisation and industrialisation generate a large quantity of waste water, he said adding inadequate arrangements for its treatment and disposal are affecting the water bodies in and around national capital.

Stating that one-third of water bodies in the capital are polluted, Trivedi said: "Though we generate about 22900 million litre waste water per day (MLD) through domestic activities and 13500 mld through industries, treatment facilities are available for only about 6000 mld of domestic and about 8000 mld of industrial waste water."

Increasing levels of fluoride, arsenic, zinc, nitrate and cadmium in the water need to be tackled on priority basis as they are posing health hazards for the people, professor at Nuclear Research Laboratory, Indian Agricultural Research Institute, Dr P S Datta said.

"Metals such as zinc and cadmium do not affect human health individually but their synergistic effect could be dangerous for humans," he said.

People need to ensure the water quality as it might not affect their health instantly but manifestations might come even after 15-20 years, Datta added.

Bureau Report