Geetanjali Krishna: Raising a toast to Zimba

As Assam burns in the vengeful flame of riots and killings, the news filtering through on the Net tells me that over 1.7 lakh people from 400 villages in Kokrajhar, Chirang and Dhubri districts are now homeless and sheltered in 128 camps that dot the conflict zone. In my mind, I picture the conditions in those crowded refugee camps. Given the monsoons and the burgeoning population of the camp, it’s only a matter of time before waterborne diseases take on the job that the rioters began. No wonder, then, that my thoughts turn to a maverick inventor, working in a makeshift workshop/laboratory on the terrace of his house not that far away, in Kolkata. Suprio Das, engineer-turned-inventor, recently designed the Zimba, a small contraption that can be attached to hand pumps and provides scientifically chlorinated water at a nominal cost.

“Chlorinating water is one of the simplest and most effective ways to control waterborne diseases as chlorine kills most of the pathogens that cause them,” said Das when we chatted earlier this week. “Every day, 2,000 children die because of waterborne diseases — and almost half of them are India’s rural and urban poor. I wanted to help in some way, so I devised the Zimba.” The Zimba is essentially a low-cost chlorinator that can be fitted to existing hand pumps or taps. It makes water safe to drink by mixing chlorine at the required concentration. It chlorinates water at the point of use, rather than at the point of storage (where there are chances of contamination). “Also, it has no movable parts and so requires little maintenance except the regular addition of chlorine. The fact that it doesn’t require electricity is an added bonus,” he said. Further, compared to conventional water purifiers, the Zimba can handle thousands of litres every day and is, therefore, able to supply more people with clean water.

Chlorinating water isn’t a new idea. However, the cost of the infrastructure required is prohibitively high for economically backward areas. Zimba, the idea for which originated from D-Lab at the Massachusetts Institute of Technology, has refined a design that is not only accurate but also inexpensive. Which is why it could play an important role not just in times of emergency and conflict, but also in the everyday lives of tens of thousands of India’s poor. Currently, the Zimba is at the end of its trial period in the field sites of Dhaka’s International Centre for Diarrheal Disease Research. “The results at the end of two months have been quite promising — the four Zimba prototypes there have provided safe drinking water at the rate of merely Rs 60 per month per family,” said Das. Another prototype is being tested in an Odisha village, where an NGO is selling Zimba-chlorinated water at Rs 5 for 20 litres.

So far, Das has made all the Zimba prototypes himself, on his terrace. “Zimba needs funding, or at least, marketing support. I want government and non-government agencies to try it rather than verbally convince them that it works,” he said. Meanwhile, he continues to work on it, unpaid and largely unrecognised yet — having given up a promising career as an electrical engineer. What drives this inventor who says that his innovations come from the heart rather than the head? “It is very simple,” he said. “As an engineer I find that 90 per cent of our designs are being created for not even 10 per cent of our population. It’s time we started creating useful products to improve the lives of people like them....”