A recent sampling exercise by Hindustan Times at 18 complaint-prone locations in Delhi found that nearly 44% of the samples violated basic microbiological safety standards.
The samples were collected from domestic taps, DJB tankers, and public water ATMs, and were tested for total coliform bacteria and Escherichia coli (E. coli).
The results showed that eight samples tested positive for total coliform or E. coli, indicating faecal contamination in drinking water.
The contamination was concentrated in domestic tap connections, with West Delhi's Rajouri Garden recording the highest contamination levels.
The findings raise concerns about the ageing and corroding network of sewer and water pipelines, which may be allowing localised intermixing of sewage and clean water.
Experts say that the contamination levels detected indicate systemic vulnerability rather than isolated household plumbing issues.
The Delhi Jal Board (DJB) has been urged to carry out targeted inspections and replace old pipelines to prevent further contamination.
