The National Green Tribunal (NGT) has been presented with alarming data confirming widespread contamination in rainwater harvesting systems in Delhi's Dwarka area. The Delhi Jal Board (DJB) informed the tribunal that recent inspections found fecal coliform bacteria in a majority of sampled pits, raising serious concerns about groundwater pollution.
Persistent Contamination Across Dwarka Societies
In a report dated October 30, 2025, and uploaded recently, the DJB detailed the findings from a sampling exercise conducted in September last year. The board collected fresh samples from rainwater harvesting (RWH) pits in 144 Group Housing Societies (CGHS) in Dwarka. Shockingly, the presence of fecal coliform was detected in samples from 124 of these societies.
This latest inspection was part of an ongoing case. The NGT has been hearing a plea since 2023 from a resident who alleged that poorly maintained RWH pits in Dwarka were contaminating the groundwater. The current findings substantiate those long-standing fears.
A History of Violations and Failed Systems
The problem is not new. An expert committee appointed by the NGT in May last year, which included members from the DJB and the Delhi Pollution Control Committee (DPCC), had earlier analyzed samples from 235 societies. That study found high ammoniacal nitrogen and high total dissolved solids in 180 societies.
Subsequently, a report from March 27 last year identified fecal coliform in the RWH pits of 115 societies, while four societies did not have operating systems at all. The recent September sampling focused on these 115 problematic societies, the four with non-functional pits, and an additional 25 societies where pits were found dry earlier.
Of the 144 pits tested in September, the DJB reported that 124 were contaminated with fecal coliform. Eight pits were dry, repair work was in progress in seven societies, and two pits were non-functional. Notably, three societies refused to allow officials to collect samples.
Regulatory Action and Next Steps
The DJB has pointed to sewage contamination as the likely source of the groundwater pollution. In its report to the NGT, the water board stated it had already asked the DPCC in March about past violations. It sought an action-taken report regarding the imposition of environmental compensation on the CGHS societies found responsible for polluting the groundwater.
The matter regarding disconnection of water supply to these societies is also being actively pursued, the DJB added. This indicates escalating regulatory measures against the housing complexes that have neglected their environmental responsibilities.
The consistent findings over multiple inspections highlight a systemic failure in maintaining crucial water conservation infrastructure. What was designed to recharge and protect groundwater is instead becoming a source of its contamination, posing a significant public health risk for residents of Dwarka.
