World Environment Day 2017: Suprio Das' ZIMBA gives clean drinking water at the turn of a tap
Access to clean water is a privilege that not many in India can afford. Around 77 million people in India lack access to safe drinking water in India.
The World Bank estimates that 21 percent of communicable diseases in India are linked to unsafe water and the lack of hygiene practices. Further, more than 500 children under the age of five die each day from diarrhea in India alone.
“With 27 out of 35 states and union territories in India disaster-prone, the poorest and the most marginalised will bear the brunt of extreme weather events and climate change and will find it the hardest to adapt,” said VK Madhavan, chief executive, Water Aid India.
There's where Suprio Das comes in. Disillusioned by his corporate work life which spanned 20 years, Das was inspired to leave the rat race behind and start his own enterprise.
While teaming up with an NGO in Kolkata he realised that the rural areas he was visiting lacked one essential thing — access to clean drinking water.
Das elaborates, "While visiting the slums and villages around Kolkata, I realised that social work and engineering could be combined together to come up with simple innovations that could make life better for the less fortunate. Of all the challenges the poor have to face, I found that the issue of drinking water was the most pressing. Globally ever year, over 1 million children under the age of five die from diarrheal diseases, a leading cause of which, is unsafe drinking water. In India alone, about 1,500 children die every day from water-borne diseases. Even when diarrheal episodes are not fatal, chronic diarrhoea in early childhood can contribute to malnutrition, with potentially adverse long-term consequences for child development. This was a reason I decided working on (improving access to) safe drinking water."
Das had a brainwave: instead of providing villages with clean drinking water, he thought why not provide them with the tools to purify their own water?
Das knew chlorinating water would help solve the problem. He says, "According to World Health Organisation (WHO), chlorine is the most cost-effective way of treating biologically contaminated water (bacteria and virus, and not chemical contaminants like arsenic or fluoride). Chlorine has been in use for disinfection of drinking water for almost 150 years. It has been successfully used to resist cholera, typhoid, Hepatitis A and a many other water-borne ailments for ages. Its effectiveness is time-proven and currently needs no statistical evidence."
That's how he started to try and design an automatic chlorine doser that would have no moving parts and work without electricity. With encouragement to work on this project by D-Lab at MIT, Das soon had a team of international students to help him. After years of false starts and his students distancing themselves and funding running out, ZIMBA was born.
ZIMBA is like a 'water treatment plant' in a box that attaches to almost any source of water — handpumps being one. Here's how it works:
The 12-kg device (with food-grade fiberglass shell) can be set up in 30 minutes without the need for any special tools. The device can be fitted to an existing water source like a hand-pump, the tap of a rainwater harvesting cistern or a faucet of a piped water system. It harnesses the principle of an automatic siphon to add a set amount of chlorine per water batch. Because it is designed without moving parts (electricity is a distant dream in these villages), ZIMBA works without electricity.
ZIMBA managed to conquer the hurdle of purifying water without electricity as well as regulating the amount of chlorine in the water.
Unlike conventional water purifiers, ZIMBA negates the need to replace expensive cartridges and is making waves in the industry for being robust – a pertinent feature required in tackling this type of societal problem. The fact that it is gravity-powered means that there are no expensive electricity bills or any unreliable power sources such as batteries, particularly in rural settings.
Das admits funding the project hasn't been easy: "Barid Tarafdar joined me as a partner and together we formed the company. Some funding came from friends and well wishers in an informal way, and lot of it has been self funding (from Barid and I)."
ZIMBA was first evaluated by researchers from Stanford University in the slums of Dhaka, Bangladesh, to check the consistency and accuracy of dosing. A paper has also been published by these researchers. Thereafter, ZIMBA has been installed in slums, villages and schools of West Bengal and Odisha through NGOs working in those areas. After the last devastating earthquake in Nepal, Das had also installed two of the devices as a temporary measure for safe drinking water for two villages there. The scientist has also recently exported two units to Purdue University for their safe water projects in the Dominican Republic and Kenya.
As for future plans, Suprio talks about expansion of ZIMBA and providing more villages with clean water.
Which still leaves us with one question — why the name 'ZIMBA'?
"Why, didn't you like the name?" Das asks, with a laugh. "I didn't want the name of the device to be India specific. And anything with 'Z' has a zing to it right? If I call someone whom I have not spoken to for ages, they won't remember my name, but they remember ZIMBA!"