Fly ash continues to haunt Ennore residents

Chennai: In the fishing hamlet of Nettukuppam at Ennore, about 150 homes have been grappling with a life-and-health problem for the past several years — dust, wheezing and year-round damp terraces with blackish-grey deposits. The reason? Hardly a kilometre away, swathes of fly ash mixed with river sand lie uncleared along the floodplains of Kosasthalaiyar river, near the North Chennai Thermal Power Station, even as four years have passed since an National Green Tribunal order called for their removal.

These fly ash particles — a powder-residue produced when coal is burned in thermal power plants — are the same remnants from the 2017 leak in fly ash slurry pipelines of Tangedco, when thousands of tonnes of toxic ash flowed into Ennore creek and the Kosasthalaiyar.

“Problems arising from the proximity to fly ash have become a part of the lives of villagers living within a 4-5km radius. Children show symptoms of wheezing at night,” said Aravindan, a resident from Nettukuppam.

While NGT had ordered the removal of fly ash deposited along the creek, river bed and the flood plains and the fixing of leaks in pipelines that carry the ash slurry, a visit by TOI to Ennore and nearby hamlets revealed that Tangedco is lagging.

Along a 1.5km stretch of flood plains along the Ennore pipeline road — which houses Tangedco pipelines — ash-mixed river sand remained spread over acres. Hot water leaks from at least two holes along the pipeline, and several sections are rusty. Residents said that desilting of the Kosasthalaiyar is incomplete at several sections, mainly near Athipattu panchayat. “Fly ash along the Buckingham Canal side has to be cleared too. During low tide, fishermen can see ash at the bottom of the river bed,” said Srinivasan, a resident-activist.

Tiruvallur collector M Prathap, who launched projects for ₹28 crore to desilt the river last year, said, “About 80% of the first phase is complete. As it is a continuous project, we have to take approval to begin the second phase.”

The thermal plant generates 2,000 tonnes of fly ash every day. While the dry ash is stored in silos inside the plant premises, the wet ash (mixed with water) is dumped into an ash dyke (pond) at Seppakkam through four pipelines. From there, the ash is picked up by cement and construction industries, and the water is filtered and sent back to the plant through two recovery pipelines.

Tangedco officials said that since the court order, 12.39 lakh tonnes of ash have been removed in a phased manner, by floating tenders and in coordination with the water resources department. “All ash pipelines have been replaced, though deadlines were missed. Only the recovery pipelines (carrying water) are old, but their leaks have been plugged. As for fly ash removal, only select portions are yet to be removed, and tenders will be floated for this soon. A few tenders are on hold owing to the recent elections,” an official said.

Tamil Nadu Pollution Control Board member-secretary E Saravanakumar said Manali-Ennore Restoration and Rejuvenation Council, which was formed in 2024, keeps pollution levels in check. “The joint chief engineer conducts regular inspections. There has been no leak of fly ash after the incident in 2017,” he added. A TNPCB engineer, however, said water pipelines have leaks from time to time, but all fly ash pipelines have been replaced and strengthened with cement holdings.

Environmentalists say the area needs a complete revamp. “At the ash dyke, ash seeps into the ground — due to the lack of proper lining — and then into canals too,” said Save Ennore Creek Campaign volunteer Durga Moorthy.

State govt carried out a study with Indian Institute of Technology Madras to strengthen the ash pond and reduce pollution, but progress has been minimal. “The study is done. Efforts to strengthen it will begin soon,” said Govinda Rao, managing director, Tamil Nadu Power Generation Corporation Limited.

For fishermen, it has become a livelihood issue. “There was a time when crabs and prawns used to be abundant here. Now, even the fish has been poisoned,” said Devan, a fisher-resident.