Experts call for recycling of grey water in the

The water table, which was just 30 feet below the ground in 1960, is now at 1,350 feet, and one of the reasons is that most water conservation techniques followed in cities such as Mumbai and Bangalore are not followed in Chennai.

Professor Navaneetha Gopalakrishnan of Anna University’s Environmental Studies Department said, “Grey water harvesting has yielded results in both Bangalore and Mumbai.” Every day Chennai generates millions of litres of sewage, which can be recycled at a minimal cost of Rs 10 per 1,000 litres. This, according to experts, is cheaper than desalination in producing clean, usable water, which costs around Rs 50-60 per litre. The water recycled from grey water is about 95 per cent pure and can be used for all household purposes except drinking.

The Mumbai Municipal Corporation has proposed to make it mandatory for all housing societies to recycle grey water. Recommending a similar step by the Chennai Corporation, Dr Ramachandran of the Climate Centre, Anna University said, “Unless there is political and policy backing to implement a green technology such as this one, it will not serve its purpose completely.”