More than 500 fish killed in Tolka over discarded tyre

Blocked sewage network overflowed into river, killing trout, stoneloach and minnow

Inland Fisheries Ireland (IFI) has said it believes more than 500 fish were killed following a sewage overflow in Dublin's River Tolka, caused by a discarded car tyre.

The dead fish were reported on Tuesday evening and the IFI investigated.

It said the kill area was an approximately 2.7 kilometre stretch of the river from Mulhuddart Bridge downstream to Connolly Hospital.

“While the extent of the fish kill is still being quantified, it is thought that the final number of mortalities will be in excess of 500 fish,” it said in a statement.


The fish killed included adult and juvenile brown trout, Stoneloach and Minnow. Live fish were found immediately upstream of the affected area, it said.

Ervia, the semi-State body that looks after the country’s water infrastructure said the event occurred after the nearby sewage network become blocked with a tyre.

“The sewer is located close to the Tolka River and the obstruction resulted in the discharge of sewage from the manhole to the adjacent river,” it said.

“Investigations found that a car tyre was the main cause of the blockage.”

Crews were dispatched on site to unblock the system and returned the following day for further maintenance work. The Environmental Protection Agency and Inland Fisheries Ireland were alerted.

“We are appealing to members of the public to refrain from putting items into the sewer network that can affect the capacity of the sewer and cause overflows which have a negative impact on the environment,” Ervia stressed.

“Materials such as rubble, tyres and household waste such as fat, oils, and grease and items such as wipes, sanitary products and nappies should never be put into the sewer network.”

Mark Hilliard

Mark Hilliard

Mark Hilliard is a reporter with The Irish Times