By R.Swathi and T.Shanmugavalli
“Implementation of rainwater harvesting will pull us for a couple of months, but implementation of greywater harvesting, will ensure sustainable water availability,” points out A.D.C. Rajasabai, a resident of Coral Samudra, 2nd Seaward Road, Valmiki Nagar. His family has implemented greywater harvesting in his apartment for the past six years and is proud that they have not bought water since its implementation six years back.
“Rainwater harvesting happens when we have rains. However, we take water from the earth every day. Thus, is it not pertinent for us to return water to Mother Earth regularly? This was the crux of my thought for developing a greywater harvesting system,” explains Rajasabai, a postgraduate from IIT Kharagpur.
Greywater is water from sinks, washing machines and the bath area and is safe for harvesting as it contains fewer pathogens than blackwater from closets. Greywater is 40% of our regular water usage.
Rajasabai relocated from the USA nearly 20 years ago. He chose to settle at Thiruvanmiyur thinking that it is near the shore thus water would not be a problem. “But, just like the whole city, this locality too was reeling with water shortage and people were buying tankers of water. We, in our family, were wondering if we had made a mistake coming back, leaving our cosy life in the US,” he recalls.
Thankfully, his thoughts only motivated him to find a solution to the water problem. Soon greywater harvesting became a family project. His then 7th-grade son drew the first prototype with inputs from his daughter studying architecture at Anna University. “Back then this was a new concept and thus there was no awareness of it. While it was becoming a mandate by the Tamilnadu government for industries, there was not even a prototype available for a domestic setup. I was thus challenged to build a system from scratch,” he explains.
When an idea is new, not only is working on it an ambition, but its implementation in a community is a challenge. Mrs.Rajasabai explains, “Definitely everyone had apprehensions. However, the desperate need for water and the thought of ‘independence from water tankers’ superseded it. Also, since the concept was unheard of, they gave us full reins.” Soon the Rajasabai family saw themself engrossed in the project, which they called ‘Toja’.
But is greywater safe for reuse? “Absolutely! In a domestic setup, we can use greywater which has a little amount of soap and pathogens which becomes a nutrient for plants,” points out Rajasabai and adds, “We are using sand which is the world’s best filter for greywater. It is this water that we pump back into our home.”
The final prototype of the greywater harvesting system was perfected by the family into a unique patented process that makes it cost-effective, safe, silent, odour and trouble-free, powered by gravity and a natural watering source for the local plants and trees. After more than 10 years of learning, and expert inputs from the now grown-up children, team Rajasabai tasted success. “Since 2018, there has been no looking back. This along with rainwater harvesting has helped us in maintaining our water table. Not only us, but the nearby apartments have also reaped the benefits from our systems. None of us have called for a water tanker since then. Also, previously, we had 6 borewells in our apartment. Now we use only one,” says Mrs.Rajasabai.
In an urban setup, where each inch is precious, how much space will the greywater harvesting system occupy? “Approximately, 4×4 feet space, for one patented filter. The essential part is that apartments must have separate greywater pipes from the bathrooms. In such a case, the pipes can be routed through a small collection tank,” he explains. The collection tank is the only visible part of the system. Rajasabai has also provided a mechanism wherein the greywater can be routed to the sewage system in case needed, like during the rains when the water table is brimming.
In a city and time when apartments largely depend on water tankers for their daily needs, Rajasabai’s family have shown that sustainable water management systems are the only way forward.
While necessity is the mother of invention, those who succeed owe their success to perseverance. And the story of Rajasabai’s family is no different. Mrs.Rajasabai was recently awarded the patent for their greywater harvesting system. Interested readers can contact the family through Enhydro Technologies; Ph: 94445 13511, [email protected]; Instagram: @toja.greywater.
Fantastic Rajasabai, proud of you
Excellent initiative by Mr Rajasabai.
I wish this valuable information to benefit the community at large in finding a lasting solution to the prevailing water scarcity.
Thank you very much for the valuable information.
Excellent initiative for the upcoming water scarcity.
I desire to implement the grey water treatment .PL do help with your innovative technology.
Grey water in a appt set up can be reused for toilet flush since grey water is from bath, sinks, and washing machines . Grey water can be passe.d thru simple filtration so that it can be reused for toilet flush. This has two benefits. It reduces overall water requirement by 30%. Also stp sizing and stp power consumption can be reduced since now a smaller stp is required.
Well done. I introducing myself as V.Subramanian, a Retired Engineer and want to implement your wonderful project in our Retirement Home at Bangalore which has about 160 flats and 200 Residents. Will discuss with our people and get back soon. Thanks.
Excellent Sabai. Congratulations Sabai. Really I am very proud of you Sabai.
lovely initiative,
God bless the venture
Excellent system thanks for valuable guidelines
Great initiative!
This article is an eye-opener for the residents living in communities to take forward this initiative and implement it for the larger benefits to all.
Very nice .
It will be very useful in North India also as water level is depleting .
Very Good.
It’s excellent initiative and appreciate it. Governments should take the initiative and make it compulsory for large gated communities. In addition to that we should install the flush tank with two buttons , so that for urinals water usage will be less and source itself we can minimize water consumption.