WATER WATER EVERYWHERE
As Chennai suffers from an acute water scarcity, faulty architecture and futile urban myths invalidate its rain water harvesting systems.
Bhuvanesh Chandar, Abhinaya K, Adithyan,
(A group assignment that was originally written on 27/07/2019 as a part of the ACJ curriculum)
Like freshly brewed coffee that drip feeds into a container, a fresh harvest of water trickles through a carefully placed system of pipes, that runs along the walls of a multi-storey apartment, only to end up in a huge syntax tank waiting to be sent to a water-treatment set up. “We’re even constructing a well, to conserve the water that overflows from the storage units, which we previously released into the ground,” says Prakash, the manager of apartment community Sabari in Sholinganallur, which seems to have perfected the creation of an efficient rain water harvesting system. In the city’s most recent spell of drought on 26th June, the community conserved 50,000 litres of rain water from a spell of rain that lasted for about one hour and 10 minutes.
In 2003, the state government of Tamil Nadu, under the order of late Chief Minister, J. Jayalalitha, had passed an order, which stated that it was compulsory for every household to have a working rain water harvesting system. Yet, many households failed to implement an effective system. “When I did a survey in 2005, which chronicled the expert opinions of plumbers and well-diggers, to show how the rain water harvesting system had been implemented across the city, we found that not even 40-45% per cent of the households had implemented a rain water system” states, Dr. Shekar Raghavan, the director of Akash Ganga Trust, The Rain Centre, which aims to spread awareness about rain water harvesting systems to households and commercial buildings.
Moreover, most households seem to have implemented an inefficient system, just to meet the legal requirements in order to get a permit. Faulty architecture and its implementation seems to hamper the efficiency of the system. “One of the most basic issues is that, concrete floors in apartments keep rainwater from percolating into the underground. Secondly, there are no plants or trees visible in the cities, which leads to soil erosion”, says K.J. Antonji, who pioneered a rain water harvesting technique called ‘ The Syringe Technique’,that enables the storage of fresh rain water several metres below sea level for future use. “Poor planning is another reason. In fact, many architects, these days, do not understand the requirements that have to be met to implement a good system,” says Prakash. Even households which have implemented a technologically-superior system, seem to lose out on efficiency, as most terrace floors don’t have the necessary degree of slope that is required for the rain water to get into the coils, which in turn leads to water stagnation in the roof. This is one of the reasons as to why even the ancient techniques that were used during the Chola period, proved to be effective, as city planners were well aware of the intricate details of the system and helped conserve maximum amount of rainwater.
The fear of equipment being overpriced also seems to be a huge concern for the middle-class house owner. “But, this is just a misunderstanding” ,says Dayanand Krishnan, who created a sustainable rain water system, that costs just ₹250. All he needed was a pipe costing ₹120, two T-benders worth ₹110, and a ₹20 net. In contrast to this, bigger apartments such as Sabari Terrace are willing to spend extra money to set up a complete system which also includes a water purifier. “The system we have in place cost us about ₹2.5 lakhs and 56 households benefit from it.
In the longer run, this seems to be a more sensible option, as the accumulated cost of water tankers skyrockets, especially during the summer”, states Prakash. On the OMR stretch, one load of water tanker costs anywhere between ₹2000-₹3500. “Even this is underestimating it, as we are regular customers to the suppliers. Most others charge a humongous amount, and the dried up wells around Chennai contribute to these high prices”, he adds, as even The Sabari Terrace community relies on a water tanker supply during periods when there is no rainfall. This is the primary reason due to which the community has decided to construct a well and save the extra water that usually seeps into the ground. It takes about six to eight months for the ground water to get recharged after a day’s spell of rain, and the residents of the household believe that constructing a well will prove to be an efficient solution.
While states such as Kerala seem to have perfected various rain water harvesting methods, Chennai seems to have taken a back step in this regard. “In Ernakulam district alone, 4 four billion litres of rain water have been added to the ground water level in the past 20 years” says Antoji, as he adds that the sloped roofs in Kerala add an inherent architectural advantage, which benefits this system. With the water scarcity heading towards its worst phase, it is high time that residents of Chennai embrace a solution that is well within their reach.