The recent deaths of at least 21 people in Indore after consuming contaminated tap water have once again highlighted the deep-rooted weaknesses in India’s urban water supply systems. Preliminary investigations indicate that leakages in the city’s drinking water pipeline allowed sewage to enter the supply, a problem that officials say is linked to ageing infrastructure and the close proximity of water and sewerage lines underground.
Such incidents are not isolated. Cities like Bengaluru have also reported repeated contamination scares, despite years of investment in urban water infrastructure. Experts argue that the core issue lies in India’s dependence on intermittent water supply systems, where water flows for only a few hours a day. These systems, they say, are structurally vulnerable and almost designed to fail when it comes to maintaining drinking water safety.
During periods when water supply is shut off, pipelines lose pressure, creating a vacuum that can pull in contaminated water through cracks, loose joints or illegal connections. Even when water leaves treatment plants in safe condition, it often becomes polluted before reaching households.
Against this backdrop, Odisha has emerged as a rare exception. Since 2017, the state has been implementing its ‘Drink from Tap’ programme, which supplies potable water on a continuous, 24×7 basis in selected urban areas. The programme currently covers 11 cities, including Puri, Brahmapur, Rourkela suburbs and smaller towns such as Nimapada, Hinjilicut and Anandpur, reaching more than 3.2 million people through over six lakh household connections.
Odisha is currently the only Indian state that formally guarantees drinking water quality at the household tap. Officials say the programme is not merely about convenience but is fundamentally a public health intervention aimed at preventing contamination.
In Puri, one of the earliest cities to adopt the model, jalasathis or “water friends” play a key role in building trust. They test water quality at the household level, read meters, collect charges and help residents shift away from water storage and filtration. According to Sunita Mishra, a jalasathi in Puri, households that once relied on boiling water or purchasing filtered water now drink directly from the tap. She says the change is also visible in public spaces, where people increasingly use public taps instead of buying bottled water.
Experts say the success of Odisha’s model lies in maintaining constant pressure in pipelines. According to Pradeep Kumar Swain, former chief executive of the Water Corporation of Odisha (WATCO), continuous pressurisation ensures that even if leaks occur, water flows outward rather than allowing contaminated water to enter the pipeline.
“In any city, leakages are inevitable,” Swain said. “But in a 24×7 system, leakages result in water loss, not contamination. Outside water can never enter a pressurised pipe.”
By contrast, intermittent supply systems almost guarantee contamination, experts argue. Chinmay Tripathi, a water management consultant who worked with WATCO until 2024, said most cities deliver reasonably treated water at the source, but contamination happens during distribution. “By design, intermittent water supply creates contamination,” he said.
Another major challenge in Indian cities is the physical layout of underground utilities. In many areas, sewerage and drinking water pipelines run dangerously close to each other, or even cross paths. This is often the result of unplanned urban growth and the absence of dedicated utility corridors.
Guidelines from the Central Public Health and Environmental Engineering Organisation recommend a minimum horizontal separation of three metres and a vertical gap of up to 1.5 metres between sewer and water lines. However, these standards are frequently violated in older cities.
Swain said that in nearly 90 per cent of contamination cases, sewerage proximity is the main cause. Tripathi added that in many incidents, household water connections pass directly beneath drains, making contamination almost unavoidable if a rupture occurs.
To address this, Odisha made detailed underground asset mapping mandatory before implementing continuous supply. Pipelines were realigned or relocated wherever sewerage and water lines were found too close. In many older cities such corrective work is difficult due to congestion, traffic and limited space.
Beyond engineering fixes, Odisha has also reformed water quality surveillance. The state created an independent Water Quality Assurance Cell under the Department of Housing and Urban Development, separating testing and monitoring from agencies responsible for supplying water. This move was aimed at removing conflicts of interest and improving data credibility.
Water samples are tested at city, regional and state laboratories, with third-party verification from IIT Bhubaneswar. Depending on local risks, up to 69 parameters are tested, including microbial contamination and heavy metals. Officials say this layered surveillance system allows early detection and faster response when problems arise.
The model has also sought to change household behaviour. Continuous supply discourages the use of underground sumps and overhead storage tanks, which can themselves become sources of contamination. In Puri, around 85 per cent of households have voluntarily removed storage tanks after gaining confidence in the system, according to Swain.
Experts caution that infrastructure alone is not enough. Trust in tap water builds slowly, especially in cities accustomed to unreliable supply and frequent contamination reports. Practices such as storing water and relying on domestic filters are deeply ingrained responses to service failure.
Even so, the Odisha experience is increasingly shaping national discussions on urban water reform. Under the AMRUT 2.0 mission, the Union government is encouraging states to move towards continuous, pressurised water supply. Water experts argue that without such a structural shift, cities will continue to face contamination risks and tragedies like the one witnessed in Indore will remain a recurring threat rather than an exception.