India, Feb. 4 -- After faecal coliform was detected in rainwater harvesting (RWH) pits at 124 of the 144 group housing societies tested in Dwarka in September 2025, the Delhi Jal Board told the National Green Tribunal that the contamination is not due to any design flaw in its RWH systems but because of poor upkeep by housing societies that allowed sewage and other contaminants to enter the pits and pollute groundwater.

In an affidavit dated January 5, 2026, and uploaded on Tuesday, DJB stated that the presence of faecal coliform establishes a contamination risk that legally bars the issuance of adequacy certificates, which are mandatory for residential societies to avail a 10% rebate on water bills. The utility said such certificates wi...