Fishers Protest Mass Fish Deaths in Kosasthalaiyar

Chennai: The mass killing of fish in Kosasthalaiyar river near the Ennore estuary has triggered protests by fishermen. They alleged that a heavily contaminated industrial discharge entered the waterway through the Buckingham Canal, threatening the fragile river-estuary ecosystem and livelihoods.

Tonnes of dead fish and other aquatic life were found floating in the water from Saturday morning, with fishermen claiming that the affected stretch extended for nearly 6-7 km, from the Buckingham Canal near Kattukuppam, past the North Chennai Thermal Power Station towards the Kolivakkam area.

The scale of the latest fish kill has revived longstanding concerns over industrial pollution in the Ennore-Manali belt, where fishing communities have for decades complained of contamination of the river, creek and backwaters.

R.L. Srinivasan, president of the Ennore Fishermen Co-operative Society, said incidents of suspected industrial discharge had become frequent. “This happens frequently. This time it is a bit more. Water mixed with chemicals is being released from the Manali side through a canal. It mixes with the backwaters and, during low tide, comes towards the sea,” he said.

Fishermen alleged that highly contaminated discharges were often released during night, making it difficult to identify the source. They have now resorted to road blockades in Ennore, demanding immediate action against those responsible for polluting the waterbody.

A fisherman from Kattukuppam said the latest fish deaths were noticed around 11 am on Saturday and had subsequently spread across several kilometres. “This is due to fertiliser factories. Because it comes through the Buckingham Canal, the scale of the impact it creates to our livelihood is huge,” he said.

Madal, Thullal, Sankara, Koduva and Irunka fish, besides prawns and crabs, were among the aquatic life found dead, he said.

“First it started with releasing of hot water decades ago. Now, they are sending all kinds of chemical water into the backwaters,” he said, referring to the industrial facilities in the Manali-Ennore belt.

The latest incident comes against the backdrop of decades of documented pollution in the Ennore estuary. The eco system was hit particularly hard by the 2017 Ennore oil spill, when two vessels collided off Kamarajar Port. The most recent major episode occurred during Cyclone Michaung in December 2023, when floodwaters inundated industrial premises in the Manali-Ennore region and carried oil into the Buckingham Canal and Ennore Creek. A government technical team subsequently concluded that oil had flowed from the premises of Chennai Petroleum Corporation Limited (CPCL) into the Buckingham Canal and reached Ennore Creek.

D. Venkatesan, secretary of Ennorekuppam Grama Panchayat, said the latest incident had caused extensive damage to the fishing community. “As many as 750 fishing boats, including fibre and mechanised boats, have been affected. At least 25,000 families are struggling as their livelihood has collapsed. Even 24 hours after around 3-4 lakh fish were found dead in the water, none of the officials from the Environment Department or Pollution Control Board had visited the site,” he said.

He said no effective steps had been taken to remove the dead fish while the decomposition had created a severe foul smell in the fishing hamlets.

Fishermen are also demanding that the source of the suspected discharge be traced through a comprehensive investigation rather than treating the incident as an isolated fish-kill event.

Meanwhile, Fisheries Department officials visited the affected area on Sunday and collected water samples. Officials said the samples had been sent to laboratories for further analysis to determine whether there had been a chemical discharge into the river ecosystem. The immediate concern, however, is the removal of the dead aquatic life and preventing further contamination’, said officials.