Mass fish death in Delhi’s Sanjay Lake: Mismanagement, not heatwave, says SANDRP

A shocking episode of mass fish death in East Delhi’s Sanjay Lake has sparked outrage among environmental groups and citizens. While initial reports attributed the incident to the ongoing heatwave and climate change, the South Asia Network on Dams, Rivers and People (SANDRP) has squarely blamed mismanagement and prolonged disruption of water supply as the primary cause.  

Sanjay Lake, spread over 17 hectares, is Delhi’s largest artificial waterbody. Historically part of a Yamuna floodplain channel, it was cut off due to urbanization. Developed in the 1970s–80s by the Delhi Development Authority (DDA), the lake was initially fed by groundwater but later polluted by sewage inflows. In 2019, DDA and Delhi Jal Board (DJB) planned sewage treatment interventions, and by March 2024 renovation was completed with DJB supplying 10 million gallons per day of treated sewage from Kondli STP.  

Reports of dead fish surfaced on May 21, 2026, with hundreds of gambusia, tilapia, and common carp floating in stagnant, blackish pools. By May 22, workers had removed 2–3 tonnes of dead fish. While officials initially linked the incident to the heatwave, activists pointed to declining water levels. “Heatwave could be a partial reason for fish death. But how can fish survive without water in the lake?” said Yamuna activist Pankaj Kumar, warning of risks to water birds if supply was not restored.  

The lake’s supervisor from DDA admitted water supply disruption had lasted six months, despite repeated assurances from DJB. DJB later claimed the pipeline was damaged by waste burning near Kondli STP, while DDA accused DJB of failing to provide alternatives like tankers or borewells. The contradictory claims exposed confusion over responsibility and highlighted poor coordination between agencies.  

SANDRP criticized the silence of key institutions. Neither DDA, DJB, nor the Forest Department has issued an explanation. The Delhi Pollution Control Committee does not monitor Sanjay Lake, leaving water quality data absent, and the Delhi Wetland Authority has remained silent despite its mandate to protect wetlands. Kondli STP, fined by the National Green Tribunal in 2024, has a history of non-compliance, and activists suspect manipulation of monitoring data.  

Despite crores of rupees spent on restoration, there is no public breakdown of expenditure, no record of fish stocking, and no clarity on pipeline quality or repair delays. 

SANDRP’s statement concluded: “This mass fish death episode amply demonstrates the level of inefficiency prevailing among the multiple agencies managing the lakes in Delhi. It also exposes the deep institutional failures affecting the water governance system in the national capital. Blaming the heat spell will only act as a cover up, allowing the real culprits go scot-free. The incident indeed warrants a thorough independent probe and strict action against all involved. Is that too much to ask?”  

The tragedy underscores the fragility of Delhi’s artificial lakes, the risks of over-reliance on treated sewage without robust monitoring, and the urgent need for accountability in urban water governance.