Water filter use in India: safety, luxury, or a threat to the environment?

While the poor lack access to safe water, wealthy individuals use RO systems. Though it is a highly effective water technology, it leads to wastage of large quantities of water.

A recent study on water filter use in Ahmedabad done by the Comprehensive Initiative on Technology Evaluation (CITE) at the Massachusetts Institute of Technology (MIT) found that household water filters were commonly used in households in Ahmedabad. The poor lacked access to good quality filters and instead used cheap, but ineffective methods of water filtration. The rich, in contrast, used reverse osmosis (RO) systems. This highly effective technology resulted in wastage of large quantities of water and thereby not environmentally friendly.

In this interview, the researchers discuss their take on the findings of the study and its implications in the context of India.

Tell us about your department and the kind of work it does.

Created in 2012, the CITE is a programme at MIT. It is comprised faculty and staff from five different departments at MIT bringing expertise from a wide variety of disciplines. CITE is the first-ever programme dedicated to developing methods for product evaluation in global development. We use a holistic approach to evaluating products designed for users at the bottom of the pyramid like water filters and solar lanterns to understand the suitability, scalability, and sustainability of a product family.

Why this study? What was the background that led you to this study?

While our study concentrated on the lowest income sector, our research spanned products across the entire range of incomes – from inexpensive cloth and jali mesh filters to expensive, branded RO filters. In India and many parts of the world, household water filters are in high demand. They are used to improve water quality as sometimes the water supplied is questionable due to contamination in the piped water and/or due to intermittent water supplies.

Water filters can play a crucial role as a stopgap technology to provide water to low resource communities without consistent, safe drinking water. However, the household water filter market in India is incredibly dynamic and complex, so it can be tough to navigate as a consumer. CITE wanted to better understand, and in turn, help consumers understand the products that could fit the existing needs. They not only wanted to shine a light on the gaps in the market but also highlight which products would best provide safe water to the poorest income sector.

CITE drew upon existing partnerships with academic institutions such as IIT- Gandhinagar, IIM-Ahmedabad, CEPT, AIDMI, and others to better understand the local context. These partnerships were immensely valuable in conducting the evaluation and will play a large part in disseminating the information to a wider community.

What do you think were the most important findings of the study? What struck you the most?

When it comes to meeting the needs of the bottom of the pyramid, the household water filter market has a tremendous gap. We found that poor families in Ahmedabad are aware of the need to filter their water, but do not have adequate tools. Conventional particle filters, including cloth and jali mesh filters, are the only category of filters available within their financial reach. These filters are widely available and very cheap. However, our lab tests showed them to be completely ineffective at making water safe or clean in terms of either bacterial contamination, measured through E. coli indicators or turbidity.

At the top of the pyramid, we found middle-to-higher income households in Ahmedabad using RO systems. Our research shows that these systems generate wastewater at rates triple that of the clean water they produce, which is a reason for environmental concern.

What do you think could be the implications of these findings in the context of India?

Although CITE looked specifically at the water filter market in Ahmedabad and the surrounding area, many of our findings could be more broadly applicable to other areas in India. While we wouldn’t want to speculate what we might find if we conducted the same evaluation in other cities and regions of India, we can ask informed questions based on our findings in Ahmedabad to help these areas think through where their challenges may lie.

We have been asked about water filters commonly found in other parts of India but not in Ahmedabad, such as candle or biosand filters, which may be good alternatives to some of the more expensive models out there. This is an important area for further evaluation, but it is crucial to keep in mind that for the economically weaker section – families living on less than $4 a day--and even some in the lower-income group (those living on about $8.50 a day), that it may be a real challenge to purchase even a $20-$30 filter when that filter is competing with other priority expenses like food, education, energy, health, and other day-to-day needs.

RO systems are very popular among demographics who can afford the technology. One question we might ask is – if in Ahmedabad, the RO filters which are so wasteful of water are primarily being used to remove high levels of total dissolved solids, would it not be possible to introduce new water softening options as opposed to RO? In other words, what substitute products can be considered, given that Ahmedabad is a water scarce region. Other options might include a greater focus on improving the intermittency of the piped water supply and also finding new and innovative ways to reuse wastewater on a household level.

How do you see the role of water purification technologies in the years to come in the context of India?

We see water filters as a complement to piped water supply which helps to bring safe water to the poor and a higher level of treated water, that is luxury water to the rich. For the demographic we most cared about (the poor), water filters can be an important stopgap technology that will continue to play an important role in providing safe water to India at large while the water and sanitation infrastructure is further developed. Today, these filters not only play a role in improving the aesthetic characteristics of water but also in important tasks like removing harmful microbes.

What could be the advantages and disadvantages posed by these developments?

Optimistically, we hope the outcome of improving water and sanitation infrastructure nationwide means more households at all income levels have consistent access to safe drinking water at a fair, accessible price. Better access to safe drinking water would equate to fewer incidences of water-borne diseases such as cholera, typhoid, and diarrhea, and fewer deaths caused by these water-related diseases.

On an already water-scarce planet, it is important to note that there are environmental implications to every decision we make and every system we build. Thus, it’s crucial that the government and other key stakeholders keep this in mind as India improves its existing infrastructure for future generations. Are there ways in which these systems can be built to both provide safe water, but also to incentivise a rapidly growing population to conserve resources? These are the questions we’re all asking ourselves, especially with the onset of the United Nation’s new Sustainable Development Goals, which have the environment and the future of the planet deeply embedded in each and every goal.

What are your recommendations to bring about a change in the current situation with respect to water safety technologies in the country?

To reflect on the situation in Ahmedabad, information sharing is needed to help Ahmedabad’s poor better understand their current water quality and which technologies may help them improve that for their health and safety. Broadly, further exploration of household water filters designed for the poor is necessary. Existing technologies are financially out of reach for many, and there is room for innovation in the market.

Water quality testing and open access to water quality data can help citizens make more informed decisions when it comes to the water treatment. In the example mentioned above, if a consumer knew that their water quality was high in total dissolved solids, it might be better for them to look at alternatives to RO, thereby directly addressing the problem with an appropriate solution such as water softening rather than with RO. This would conserve water and provide the higher level of quality that a particular customer may desire. Likewise, the low-income group would also benefit from knowing, for example, that their water is contaminated with E. coli. This could lead them to demand appropriate low cost, anti-microbial systems, such as ceramic pot filters, biosand filters, or other effective products for their needs.

Disclaimer: This article, authored by Aarti Kelkar-Khambete, was first published in India Water Portal.