The Hindu             14.11.2013

Rainwater harvesting structures planned along storm-water drains

The Tiruchirapalli City Corporation has planned to set up rainwater harvesting structures (RWH) along the storm-water drains in the city soon.

“We have storm-water drains running for about 650 km in the city and RWH structures could be put up every 10 metres along the drains. The structures will have filter beds and pipes running into the ground for up to 20 metres depth to recharge the water table. We will soon incorporate the provision for RWH structures in the design of the storm-water drains,” said Corporation Commissioner V.P. Thandapani here on Wednesday.

He was speaking at a workshop on “simple steps to achieve water sufficiency — rainwater harvesting and grey water recycling,” organised by Rain Centre, Chennai, in the city.

The workshop was meant for members of the media, architects, builders, municipal engineers, and town planners.

Mr. Thandapani, who inaugurated the workshop, pointed out that the corporation had framed bylaws making it illegal for residents to let out sullage from toilets into open drains. Once the bylaws were gazetted, the corporation would launch a campaign to sensitise residents against letting out sullage into the storm-water drains.

Emphasising the need for proper design and maintenance of rainwater harvesting structures, Mr. Thandapani said the corporation had conducted a survey recently and found that nearly 80 per cent of the 1.85 lakh properties in the city had RWH structures. However, many of them were not properly maintained and needed to be revived.

He said most of the RWH structures had not been designed properly in proportion to the built up area and open space in a particular building and the quantity of the rainwater that could be harvested.

In most buildings, RWH structures had been put up to meet minimal requirement and excess rainwater often flowed on to the streets. Builders and engineers should design the RWH structures properly to tap the maximum potential for harvesting rainwater. City residents needed to be educated more on creating proper RWH structures, he said.

Sekhar Raghavan, Director, Rain Centre, Chennai, said although the concept of rainwater harvesting had been talked about for 10 years, it had still not got the importance it deserved. Designing RWH structure for a particular site had not been well understood. These structures had not been maintained properly.

Builders, architects, and engineers had a responsibility to ensure proper design of the structures and implement the concept correctly.

The Akash Ganga Trust, which had set up the Rain Centre, had received a grant from Arghyam, a non-governmental organisation, based in Bangalore, to conduct 15 workshops on efficient methods of rainwater harvesting and grey water recycling in Tamil Nadu. Six of them had been held in Chennai and three each were organised in Coimbatore, Madurai, and Tiruchi, he said.

V. Ganapathy, Liaison Officer, SCOPE, Tiruchi, spoke.

Technical sessions were held on rainwater harvesting and water security.