With stagnant water, shut plant, Delhi faces twin crises

Delhi faces severe flooding as the Yamuna remains swollen, disrupting water supply and raising public health risks from stagnant water and outdated drainage systems.

For more than four days, the Yamuna has stayed swollen above danger marks, and Delhi is starting to feel the strain. With the river flowing higher than the outfalls of major drains, floodwaters are finding no escape, leading to persistent waterlogging in neighbourhoods across the city, particularly in north and east Delhi.

Yamuna River water recedes considerably, but Bela Raod at Civil Lines still flooded on Friday. (Vipin Kumar/HT Photo)

The situation has been further compounded by the shutdown of one of Delhi’s primary water treatment plants at Wazirabad for nearly 36 hours, disrupting supply across large parts of the city. Experts now warn that the combination of stagnant water and disrupted services could tip Delhi into a public health crisis, as the risk of vector- and water-borne diseases grows with each passing day.

Officials explained that when the Yamuna runs high, drains cannot empty into the river, creating a backflow that floods low-lying areas. “With Hathnikund barrage continuing to release water, the Yamuna is not receding. Several drains are brimming, and their outfalls are now below the river level, making them ineffective,” a senior government official said.

For residents, this means prolonged flooding in colonies close to the river, where pools of stagnant water have become breeding grounds for mosquitoes and are contaminating local water supplies. Public health experts caution that such conditions are fertile ground for outbreaks of diarrhoea, typhoid, cholera, and dengue.

Urban designer KT Ravindran said unplanned construction in ecologically fragile areas has worsened Delhi’s vulnerability. “Pragati Maidan was once a wetland on the Yamuna floodplain. Today it has underpasses that flood every monsoon. Areas like Monastery Market and ITO face the same fate. The terrain has been mapped, but planning ignores it,” said Ravindran, urban designer and current dean emeritus, RICS School of Built Environment, Amity University.

Former Delhi Development Authority official PS Uttarwar noted that many of Delhi’s drains were once natural rivers.

“Najafgarh was the Sahibi river, navigable by ships. We need to revive covered natural drains, connect stormwater drains to sewage treatment plants, and store floodwater for reuse,” he said. He warned that stopgap measures will keep failing unless Delhi, UP, and Haryana develop a joint river and drain management plan.

Wazirabad water plant shuts

The water crisis added another dimension. Flooding forced authorities to cut power supply to the Wazirabad water treatment plant on Thursday morning, halting operations. The 135 MGD plant, which supplies to vast swathes of Delhi, could only be fully restored by Friday evening.

“Due to rising water levels, parts of the plant were submerged. Power had to be disconnected, and supply phases were restored only gradually,” said a Delhi Jal Board (DJB) official. Phase 1 and 2 resumed by Friday morning, restoring supply to areas such as Azadpur, Shalimar Bagh, Model Town, Timarpur, and Jahangirpuri. Phase 3, which covers NDMC areas, Majnu ka Tila, ISBT Kashmere Gate, Greater Kailash, and parts of central Delhi, only came online by evening.

While supply has stabilised, the 48-hour disruption underscored the fragility of Delhi’s water infrastructure in the face of prolonged floods.

The repeated flooding is more than an inconvenience, experts stress – it is a health risk. Stagnant water and choked drainage in densely populated areas threaten to unleash a surge in vector-borne diseases just as healthcare facilities are themselves strained by waterlogging and disrupted access.

“As we see in any major flood, the immediate health risks fall into three main categories,” explained Dr Prashant Sinha, head of emergency, PSRI hospital. “First, water-borne diseases like cholera, typhoid, and hepatitis from contaminated drinking sources. Second, a sharp rise in mosquito-borne illnesses, including malaria and dengue, as stagnant water becomes a perfect breeding ground. Finally, we see infections from wounds and overcrowding in relief camps, leading to skin diseases, leptospirosis, and respiratory spread. Ensuring access to clean water and safe shelter is our top priority.”

While the Najafgarh basin plan has inched forward, implementation across ther basins remains years away, with feasibility studies, approvals, and funding still pending. Until then, Delhi remains dependent on infrastructure designed for a much smaller city.