Dharishini, a 24-year-old resident of Washermenpet, never anticipated that the water she consumed daily would take such a severe toll on her health. Originally from Tirunelveli, Dharishini has been living and working alone in Chennai for the past two years.

One evening, after returning home from work, she developed intense stomach pain. Assuming it was due to the spicy food she had for lunch, she took some over-the-counter medicine and went to bed. However, her symptoms worsened the next day, and she developed a high fever. She continued self-medicating, but things took a turn for the worse.

“Fortunately, my friend, who came to visit me, noticed I was not okay and took me to the nearby hospital. The doctors there informed her that I was severely dehydrated and in a state of shock,” Dharishini recalls. Blood tests later confirmed that she had typhoid fever, likely caused by consuming contaminated water. After more than a month with 17 days of hospitalisation, she fully recovered.

Dharishini’s health scare highlights the rising public health risks of water contamination in Chennai. One of the most tragic examples occurred on December 5, 2024, in Pallavaram, where three people lost their lives after allegedly consuming contaminated piped water. While initial statements from government officials denied any link between the deaths and the water supply, post-mortem reports revealed that two of the deceased had died from severe food poisoning, likely caused by ingesting contaminated water. This incident is a stark reminder of the dangers of poor water quality and its devastating effects on public health.

Rising cases of waterborne diseases

Reiterating the crisis, a study published in the Tamil Nadu Journal of Public Health and Medical Research has drawn attention to the alarming rise in cases of acute diarrheal disease (ADD) in the region. The report, titled Epidemiology of Acute Diarrheal Diseases in Tamil Nadu: 2022-2023, identified inadequate access to clean drinking water as a significant contributor. Of the 1,62,765 ADD cases reported across Tamil Nadu, 3-5% were from Chennai alone.

Impacts of delayed medical attention to waterborne diseases

Dr M Keerthy Varman, General Secretary of Tamil Nadu Resident Doctors Association, notes that hospitals in Chennai are witnessing a steady rise in waterborne diseases, particularly during the monsoon season and in areas with poor sanitation.

Sharing a particularly distressing case, Dr Keerthy says that a 48-year-old man was rushed to the hospital after three days of severe diarrhoea, extreme weakness, and almost no urine output. He was in shock due to severe dehydration, and his kidneys were failing. Tests later confirmed cholera, a bacterial infection from contaminated water.

“Although he received IV fluids and antibiotics, his kidney damage was severe, and he needed emergency dialysis. After three dialysis sessions and careful medical support, his kidney function improved, and he was discharged after 10 days,” he says, highlighting how untreated diarrhoea can rapidly turn fatal if not managed early.

Dr Keerthy reports seeing at least 50 diarrheal cases per day at Chennai’s Stanley Medical College and Hospital, with numbers sometimes rising to 100 during peak periods.

Based on his extensive experience, he also provides insights into other common waterborne diseases affecting Chennai, along with their symptoms and associated risks.

Socio-economic impact of water-borne diseases

Socioeconomic factors may often prevent many adults from seeking timely medical attention, which exacerbates existing socioeconomic issues.

In another instance, Mariam*, a Perumbakkam resident, says that the water supplied to them from the Nemmeli desalination plant tastes excessively salty and has an unpleasant smell, indicating contamination with sewage.

“All my family members were falling ill one after the other. We had frequent fevers, vomiting, and diarrhoea. The mounting healthcare costs forced us to purchase private water cans that cost Rs 35–50 for 20 litres. However, not everyone in my area could afford it,” she explains. Moreover, as they use desalinated water for bathing, Mariam’s family, like many others in the area, have skin and hair loss issues.

Read more: Pallavaram tragedy highlights why safe drinking water is a luxury for this suburb 

Government action and response to waterborne diseases

To tackle the growing threat of waterborne diseases, the government has adopted a systematic approach to address the issue. Dr Arularasan, a former Medical Officer at a Chennai UPHC, explains that when cases of waterborne diseases are reported, medical officers at the UPHCs notify the Sanitary Inspectors (SI) for immediate action. The SI is then responsible for visiting the affected patient’s home and the surrounding area to collect water samples from various sources, such as wells and lakes. These samples are sent to the government testing centre in Guindy for analysis. Based on the test results, the authorities take further steps, such as organising health camps and initiating chlorination measures in the affected locality to reduce the risk of further contamination.

Recognising the increasing risks associated with waterborne diseases, particularly from stagnant water and overflowing sewage drains during the monsoon season, the DPH issued fresh guidelines in December 2024 for water chlorination of overhead tanks, ground-level reservoirs and wells.

Emerging chemical contaminants remain unaddressed

While bacterial and viral contamination remains a significant concern, emerging chemical contaminants are also raising alarms. “Unlike traditional pollutants, conventional water treatment is ineffective in eliminating emerging pollutants like Per- and Polyfluoroalkyl Substances (PFAS) from the water system,” says Indumathi M Nambi, a professor in the Civil Engineering Department of IIT-Madras.

A recent IIT-M study, titled Occurrence of Forever Chemicals in Chennai Waters, revealed the presence of PFAS, commonly referred to as “forever chemicals”, in several of Chennai’s water. PFAS are a group of over 10,000 chemicals in everyday items like non-stick pans, raincoats, and cleaning agents. Industrial emissions, untreated domestic wastewater, and open dump sites are primary sources of PFAS contamination.

The problem is exacerbated by current water quality guidelines that do not account for emerging chemicals like PFAS. “These chemicals are not part of standard water quality testing, allowing them to leach into drinking water supplies unnoticed. Long-term exposure to PFAS has been linked to hormonal imbalances, fertility issues, cancer, and birth defects in the US. This calls for urgent action and research to tackle PFAS contamination in Chennai,” she adds.

If you want to test the quality of your water, follow this guide.

Read more: Chennai’s last lung space: Nanmangalam Lake faces an ecological emergency

Temporary solutions and long-term strategies

While measures such as Reverse Osmosis (RO) water purifiers offer a temporary solution, they are not foolproof. “Though RO systems remove the contaminants, they leave behind concentrated chemicals in the rejected water. Solutions like RO purifiers or activated carbon filters may provide some relief, but they are not a long-term solution to the broader problem of water contamination,” notes Indumathi.

Dr Keerthy suggests a more traditional approach, such as boiling drinking water before consumption, avoiding outside food, proper sanitation, and early medical intervention.

The state must ensure that citizens have access to clean drinking water. Only through continued vigilance, collaboration, and a public commitment to water safety can the city hope to reverse the rising tide of waterborne diseases and protect people from further harm.

*name changed on request

Also read:

• How long before “water for all” becomes a reality in Mumbai
• One tap for fifty homes: Water woes of women in Chennai’s Vyasarpadi