Localised water treatment combined with doorstep delivery may offer one of the most practical, scalable, and cost-effective solutions for achieving near-universal access to clean drinking water in India, according to a new study by the University of Chicago’s Energy Policy Institute (EPIC). The findings come at a time when global development agencies and governments are grappling with how to extend safe water access to the billions still consuming untreated or contaminated water. The research, conducted through one of the largest randomised controlled trials ever attempted on drinking water adoption, provides compelling evidence that simple, decentralised treatment coupled with home delivery can dramatically improve usage rates, public health outcomes, and overall sustainability.

The study, carried out in collaboration with Spring Health Water, tested the model across 120 villages in Odisha, involving 60,000 households. Its underlying premise is straightforward: while piped water infrastructure remains the aspirational long-term goal, it is expensive, slow to deploy, and often fails to provide consistently safe water. In many rural regions, even where household taps or local pipelines exist, the water supplied can be just as contaminated as groundwater or surface water due to inadequate treatment, old pipes, or intermittent supply. As a result, more than two billion people globally still lack reliable access to safe drinking water. In low- and middle-income countries, only around 14 percent of rural households have piped water within their homes, and even fewer receive truly potable water.

Recognising the dual challenge of infrastructure gaps and low trust in water quality, the researchers sought a model that could be rapidly deployed, economically viable, and embraced by users. Localised treatment plants, powered in this case by solar energy and operated by Spring Health Water, provided purified water. The key differentiator in the experiment was the convenience of doorstep delivery, which allowed households to purchase or receive clean water in containers delivered directly to their homes.

According to study co-author Fiona Burlig, an assistant professor at the Harris School of Public Policy, the research demonstrates that safe, tasteless, and easily accessible drinking water does not require the heavy capital investment typically associated with nationwide piped networks. Instead, she argues, decentralised treatment paired with home delivery ensures that households receive water that is both pure and convenient, two critical attributes required for sustained adoption. Burlig emphasised that the model proved economically sustainable, with households willing to pay more for clean water than previously assumed. This willingness, she noted, indicates substantial latent demand for safe water when offered in a form that aligns with daily needs and preferences.

To test how much households valued the water and what payment or incentive structures might maximise adoption, the researchers designed three types of contracts. In the first, households could order home-delivered water at prices that varied across the sample. In the second, households were allotted a fixed amount of free bottled water each month. In the third, households were given an entitlement to water but had the option to exchange any unused portion for a cash rebate. This approach enabled the researchers to disentangle the effect of pricing, convenience, and substitutability on water consumption decisions.

The results were striking. At low prices, uptake soared, with about 90 percent of participating households choosing to order clean water for delivery. This figure vastly outperformed alternative household-level treatment solutions, such as chlorine tablets, which typically see adoption rates of only 40 to 50 percent even when offered free of charge. The low popularity of chlorine tablets, the study asserts, is rooted in both taste concerns and inconvenience, factors that have consistently undermined their widespread use despite their affordability and effectiveness in killing pathogens.

As prices increased, demand tapered off, which is expected, yet even at higher price points the households that did choose to purchase water tended to buy enough to satisfy their full drinking needs. This suggests that for some households, the perceived value of reliable, clean water outweighs cost considerations. The rebate experiment further revealed the strength of household preference for safe water. Although relatively few households were willing to purchase water at the highest prices using their own income, very few of those given water entitlements opted to trade their allotment for cash, even when rebate levels were generous. This reluctance to forgo water for money indicates that households place significant importance on assured access to clean drinking water, particularly when health benefits are clearly visible.

One of the study’s central objectives was to evaluate cost-effectiveness, not only in absolute terms but relative to available alternatives. While chlorine tablets remain the cheapest option on a per-capita basis, they suffer from poor user acceptance, meaning their real-world impact on public health is far lower than theoretical projections suggest. In contrast, the doorstep delivery model combines high adoption with strong health outcomes, making it a powerful candidate for cost-effective water access programs. The researchers found that home-delivered water provided health benefits that often exceeded those associated with chlorine treatment, simply because far more people were willing to use it consistently.

The public health implications are substantial, especially in communities where waterborne diseases remain among the most significant threats. Regular access to treated, pathogen-free water dramatically reduces the incidence of diarrheal diseases, particularly among young children, and lowers the overall disease burden on rural households. In turn, this reduces medical expenses, boosts productivity, and improves overall well-being.

Co-author Anant Sudarshan of the University of Warwick highlighted that small rural enterprises are increasingly stepping in to provide drinking water services but often struggle to operate at price points accessible to most households. The study’s findings suggest that modest government subsidies, targeted vouchers, or similar incentive structures could bridge this affordability gap and enable sustainable expansion of the model. According to Sudarshan, ensuring that clean water is literally brought to the doorstep of rural households may be one of the most effective short-term strategies for improving water safety while long-term piped water solutions are still years or decades away.

The broader message of the study is that nations seeking universal drinking water access need not wait for massive infrastructure overhauls. Incremental, affordable, decentralised solutions can deliver immediate, meaningful impact. While the aspiration of clean, piped water in every home remains essential and should continue to guide long-term investments, localised treatment and home delivery offer a reliable, flexible, and scalable solution that can be implemented now.

As governments, development partners, and policymakers confront the urgent need to expand safe water access in rural and underserved areas, this research provides a data-backed pathway that prioritises affordability, user convenience, and health outcomes. With clear evidence of high adoption rates, strong willingness to pay, and measurable health benefits, localised water treatment and doorstep delivery stand out as practical tools capable of addressing one of the most pressing public health challenges of our time.