CHENNAI/TIRUCHY/COIMBATORE: Tamil Nadu and its capital have long struggled for water. Though the water supply has improved over the last two years, the three successive years of drought from 2017 are not to be forgotten. In 2019, the situation was so bad that industries, hotels and malls had to shut down.
To effectively conserve water, every individual has to contribute. And for this, rainwater harvesting is crucial. As the Northeast monsoon sets in, experts say rainwater harvesting (RWH) structures must be maintained well to avoid acute water shortages.
“People’s mindsets must change. Instead of simply installing RWH structures since the government mandated it, people must realise the importance. Things started improving since 2020, as during the drought, I got at least 15-20 calls per day inquiring about how to set up RWH facilities,” says R Madhav, a rainwater harvesting expert.
Launching the Rainwater Harvesting Awareness and Drinking Water Safety Week in August, Chief Minister MK Stalin said officials would visit RWH structures in homes and inspect the quality of drinking water from hand pumps. RWH structures are being installed in government offices, hospitals and schools, the CM had said.
According to Sekhar Raghavan, director of The Rain Centre in Chennai, the corporation could immerse recharge wells in locations that witness waterlogging during downpours. He said recharge wells can be immersed at a depth of 10-15 ft with a 3-ft diameter, and can be covered with a perforated lid so vehicles can ply over them. Each such well would cost about Rs 15,000 and would reduce waterlogging.
For those in small rented houses too there is a solution, says Dayanand Krishnan, a resident of Chennai. Dayanand spent just Rs 250 to come up with an impromptu arrangement to harvest rainwater. He bought two PVC pipe bends, a three-foot PVC pipe, and a Rs 20 cloth filter. With this, he created a diversion on his existing pipeline that helped rainwater flow from his 400-sq-ft rooftop to a drum, collecting 225 litres of water every 10 minutes.
“This is temporary and cost-effective. Those who have a sump can simply connect a pipe and harvest rainwater. Though it carries some silt, you won’t see any worms in the water for at least a year,” he explains.
‘Infra not maintained’
When the Chennai Metro Water department inspected RWH structures in government schools in Chennai, it found that the structures were not being maintained and didn’t serve any purpose. Numerous schools in the State don’t have adequate water facilities, especially in summer. In 2019, the TN Water Supply and Drainage (TWAD) Board identified government schools without RWH structures and installed them.
“Though all government schools have RWH structures, they were completely blocked due to poor maintenance. Hence, rainwater was not being collected despite bountiful rains last year. We are now desilting all RWH structures,” says a Metro Water official.
“Following the 2019 drought, most buildings were equipped with RWH structures. But residential complexes maintained them better than commercial buildings. Most people were not even aware that RWH structures had to be desilted before every monsoon,” the official adds.
While it is mandatory for all buildings to have RWH structures, most new ones in Erode don’t have them or they exist only for namesake, say local activists. “It is rare for RWH to be successfully implemented in buildings,” says Kannaiyan, of Satta Pachayat Iyakkam.
Garment industry reaps benefits
Tiruppur Exporters Association (TEA) treasurer P Mohan tells TNIE rainwater harvesting is taken seriously by exporters and garment units in Tiruppur. Most units have rainwater pits with a capacity of between 5,000 and 25,000 litres.
These facilities have created large rainwater pits that collect between 25 lakh and 1 crore litres of water. A factory unit in Vattamalai has a capacity of 25 lakh litres, he says, adding that most of this water is recycled and used in toilets, and for cleaning purposes in the mills.
Structures being revived
Coimbatore City Municipal Corporation (CCMC) Commissioner Raja Gopal Sunkara says stormwater drains have been cleared, and an integrated complaints redressal system is being developed for residents to lodge queries on waterlogging.
TWAD officials say they have launched a programme to revive existing RWH structures and create new ones. “Funds have been allotted. The structures in several buildings are dysfunctional, and our aim is to revive them. We conducted an awareness drive in October, and plan to do more,” a TWAD Board official explains.
Showers wasted last year?
“Though all govt schools have RWH structures, they were completely blocked due to poor mainten-ance. Hence, rainwater was not collected despite bountiful rains last year. We are now desilting all RWH structures,” said a Metro Water official
(In this series, TNIE focuses on the need to conserve water before it’s too late)
