Experts and the local fishing community allege that fish are dying due to sewage and chemical contamination.

news Environment Tuesday, November 28, 2017 - 17:35

In what has now become a worrying annual affair for the residents of Chennai, scores of dead fish washed ashore from the Adyar River on Monday evening.

While fishermen blame sewage contamination of the river, the government is blaming an excess of fresh water for the death of the fish.

According to eyewitnesses, the fish washed ashore at 4.30pm on Monday evening near the Thiru Vi Ka bridge. Two kinds of fish – madavai and jalebi – were washed ashore. Scores of dead fish were found on the shore of the river that is regularly used by fishermen to procure their daily catch.

This has raised alarm among members of the fishing community, who accuse the Chennai Metro Water Board of releasing untreated sewage into the water body. 

"This has become very common during the monsoons. The Metro Water pipeline that is connected to the river releases untreated sewage, and this is killing the fish," alleges K Saravanan, a fisherman from Urur Kuppam. "People eating fish from these waters now will definitely be affected," he adds. 

When TNM contacted the Metro Water department, officials strongly denied the allegations and demanded proof of water contamination.

Fisheries Minister Jayakumar, meanwhile, offered another explanation. "Good fresh water passed through this water body. Due to this, the salt content in the water reduced. That is why the fish have died," he said.

The Minister directed officials to procure samples to conduct further tests and determine the cause of the fish deaths. 

Environmentalists, however, scoff at the Minister's explanation. "Reduced salt levels are definitely not why the fish are dying," says Rahul Muralidharan, a marine biologist.

"The fish that have been found on the shore are species which enter estuaries over sand to feed on plankton and algae. But the sand in the Adyar estuary contains toxic material such as sewage, medical waste and hazardous chemicals. In such a case, the Adyar estuary will be a low oxygen zone, suffocating the fish to death," he explains. 

In January 2015, five lorryloads of dead fish were carried out from Besant Nagar after they washed ashore. Fishermen had blamed untreated hazardous wastewater from hospitals and residences for the incident, but no action was reportedly taken. In 2016 too, according to the Coastal Research Centre, dead fish washed ashore in Besant Nagar, leaving local fishermen and environmentalists worried. 

"It has become highly common for dead fish to wash up in this area. It is the Pollution Control Board's responsibility to constantly monitor the quality of water," says Pooja Kumar of the Coastal Resource Centre.

"They need to first conduct an assessment on the nature of effluents being released into the water. Following this, the Water (Prevention and Control of Pollution) Act of 1981 will have to be enforced to protect the water body," she adds. 

Environmental activist Nityanand Jayaraman meanwhile pointed out the lack of action on the part of the government in his Facebook post, where he says, “It is not news if fish die in Chennai's rivers. It will be news if they lived.”