CHENNAI: A preliminary bacteriological report issued by the State Water Laboratory in Guindy on December 30, 2025, has confirmed that the drinking water supplied to Karlambakkam village in Tiruttani taluk was contaminated with E-coli bacteria of faecal origin, lending weight to the allegations that polluted water had led to the deaths of two residents last month.
The report on samples collected on December 28, 2025, accessed by TNIE, showed that tap water samples from four households in Karlambakkam Colony were found to be of “poor bacteriological quality, with the presence of E-coli-I of faecal origin”. The remarks column stated that “other pathogenic organisms causing Acute Diarrhoeal Disease are absent on this occasion”.
The report warned that supplying drinking water without chlorination can lead to outbreak of water-borne diseases. In contrast, samples drawn from the main road tap and overhead tank were marked “satisfactory,” indicating contamination occurred within the colony’s internal water distribution system rather than the source. Tiruvallur Collector M Prathap said, “We can’t treat the preliminary report as the final conclusion. We must get viscera report.”
Water quality being monitored daily after contamination detected: Officials
The Guindy laboratory also prescribed a clear method of disinfection, directing that 4 grams of BIS-grade bleaching powder (32%-34% chlorine) should be used for every 1,000 litres of water in overhead tanks or sumps, with a minimum contact time of 30 minutes before supply, to ensure the elimination of harmful bacteria.
The two victims were identified as C Elumalai (60), a mason who died on December 25, and V Sudha (36), who died on December 27, both residents of Karlambakkam colony in Pallipattu taluk of Tiruvallur district. Several other residents were also hospitalised with similar symptoms during the same period.
Elumalai was first admitted to a private hospital after developing diarrhoea, fever and severe headache, and was later referred to the Rajiv Gandhi Government General Hospital (RGGGH), where he died. His elder son E Sampath said that his father had no previous health issues.
“My father was healthy and active and worked as a mason. At first, we did not notice anything wrong with the water, but later people in the village started talking about complaints. Around the same time, my father developed diarrhoea and vomiting. He was admitted to a private hospital, but doctors could not give a clear diagnosis. When his stomach pain became severe, he was referred to RGGGH, where he died,” he said.
Sudha’s 17-year-old son said the water had shown visible signs of contamination before his mother fell ill. “For about a week before my mother’s death, the water used to be in black colour first and then turn normal. We used it for everything at home. Within two days she developed diarrhoea, vomiting and fever. She was taken to the Konattempettai PHC and later to Tiruttani Government Hospital. She was brought back home, where she died,” he said.
Both families said they were not informed about the preliminary laboratory findings. Assistant Director of Panchayats KS Yuvaraj told TNIE, “Even before the incident, we checked and ensured that the panchayat had a proper borewell and sewage system. We are monitoring all panchayats in Tiruvallur district. We did not receive any written complaint from residents. Action would have been taken if we had received any such complaint.”
Health department officials said water quality is being monitored daily and that chlorination and other disinfection measures have been carried out following the detection of contamination.
Meanwhile, residents alleged that complaints about foul smell and discoloured water were raised before the deaths but were not acted upon, triggering protests after more villagers were hospitalised.