Periyar River Remains Critically Polluted, National Data Points to Grave Public Health Risk

India, KOCHI, April 18, 2025:The Periyar River, one of Kerala’s most vital freshwater sources, continues to suffer from alarming levels of pollution, with contamination recorded at all major monitoring sites in Ernakulam district, according to the latest figures from the National Water Quality Programme (NWQP) up to December 2024.

The persistent degradation of water quality has been attributed to a combination of untreated industrial effluents and rampant discharge of septic waste. Testing has revealed dangerous concentrations of faecal coliform (FC) and faecal streptococci (FS), both indicators of severe microbial contamination. Public health experts warn that these pollutants are directly linked to rising cases of gastroenteritis and other waterborne illnesses in the region.

Recent readings have recorded FC levels as high as 4,000 MPN (most probable number) per 100 ml in not just the Periyar, but also the adjoining Kochi backwaters and Vembanad Lake — far exceeding safe limits for primary water use.

Environmental Activists Demand Accountability

“Despite minor fish kill incidents last month, there is an alarming level of administrative apathy. Pollution is evident, but authorities continue to downplay the issue,” said Purushan Eloor of the Periyar Maleenikkarana Viruddha Samithi, a long-standing environmental advocacy group.

In a report submitted to the National Green Tribunal (NGT), the Central Pollution Control Board (CPCB) confirmed that none of the 13 sites monitored between January and October met the minimum standards for outdoor bathing. Parameters such as dissolved oxygen (DO), pH balance, biochemical oxygen demand (BOD), and microbial indicators remained persistently non-compliant.

Key sites with severe contamination include:

• Irumbanam: FC at 11,000 MPN/100ml, FS at 4,100 MPN

• Kalamassery: FC at 3,400 MPN

• Brahmapuram (Kadambrayar): Floating debris, high turbidity, FC at 1,400 MPN

• Kochi coastal sites (Wellingdon Island & Thoppumpady): FC levels over 2,000 MPN

Environmental activist Shibu Manuel of the Green Action Force, whose case is currently being heard by the Kerala High Court, highlighted the disconnect between state claims and national data. “Despite repeated denials, national agencies have consistently detected chemical and heavy metal contaminants, particularly in stretches near Eloor and Edayar,” he said. “We urgently need a Periyar Basin Authority. Existing bodies lack the political will and operational focus.”

NGT Proceedings and Ongoing Investigations

The NGT is concurrently hearing a suo motu case based on a Times of India report published on May 6, 2024, which flagged the presence of heavy metals in fish caught from Kochi waters. In response, the tribunal has directed the National Centre for Coastal Research to conduct a comprehensive assessment. The Kerala State Pollution Control Board has sought an additional two months to complete its own investigation. The next hearing is scheduled for July 14, 2025.

As public outcry intensifies, environmental groups, civil society, and scientific bodies are urging the government to take immediate, coordinated action to safeguard one of South India's most ecologically significant river systems.