‘The river was effectively sterilised’: At least 5,000 fish dead in Co Cork fish kill

A fish kill has left at least 5,000 fish dead in a tributary of the Blackwater in north Cork.

Inland Fisheries Ireland (IFI) has opened an investigation into the cause of the fish kill on the River Allow near Freemount that was first noticed by Cork County Council officials on Sunday.

The Allow, which rises in the Mullaghareirke Mountains in Sliabh Luachra on the Cork-Kerry-Limerick border, flows for around 37km through Kanturk before it joins the Blackwater.

According to IFI, the pollution spill occurred in a Special Area of Conservation on the river, and the affected area is a noted spawning habitat for fish including salmon and brown trout.

IFI officers are still attempting to determine the scale of the kill, with fish deaths observed up to 4km downstream of the source location, said the IFI in a statement.

A major fishing competition scheduled for this weekend has had to be cancelled after the incident.

Among the fish found dead in the Allow, which joins the Dalua before entering the Blackwater, were juvenile Atlantic salmon, brown trout, lamprey, eel, stone loach, roach and dace.

IFI staff, who were on site on Sunday when first notified of the kill, were again on site on Monday to investigate the pollution event and assess the extent of the impact on the local environment.

Water samples have been taken from the river to gather evidence of the discharge, and source point of contamination, to advance any potential prosecution, said the IFI in its statement.

Uisce Éireann has a water-treatment plant in Freemount near the Allow. In a statement issued to RTÉ News, the company said it is investigating a reported spillage at the plant.

A director of Inland Fisheries Ireland (IFI), Sean Long, has described a fish kill as “heartbreaking for the community”.

Mr Long told RTÉ radio’s Morning Ireland the IFI received a call on Sunday afternoon about a spillage at the nearby water treatment plant.

“A local senior fisheries environmental officer went to the location and began an inspection of the river downstream of the plant. And unfortunately he was met with a scene of devastation, really the only way to describe it. And the river was littered with dead fish, trout, salmon fry, lamprey, eel. There were no insects, even flies, beetles, anything, any indicators of life,” Mr Long said.

“As anyone who looked into the river will know, it’s a living, dynamic habitat. You know, insects, the fish darting about. But the river was effectively sterilised, for roughly about 4km or 5km, which was mapped out on Sunday. 

“It’s an ecological disaster for the fish in the river, at a time of already significant biodiversity loss. It’s literally heartbreaking for the community and particularly the anglers there,” Mr Long said.

IFI officers walked along 8km of the river yesterday and found there was no sign of further fish kills down river towards the town of Kanturk.

“We think that the damage was done, either Saturday night, Sunday. And then it diluted and washed down through the river.” Mr Long was cautious about stating the cause of the fish kill but said they had “a fair idea” of what had caused the incident.

Dan Dennehy, a member of Kanturk and District Trout Anglers, told The Irish Times that club members as well as other anglers in Duhallow were devastated over the fish kill.

“We were due to host the Trout Anglers Federation of Ireland (TAFI) River Interprovincials in Kanturk this Saturday with 40 anglers due to take part so it was a big event for the club.

“But now we’ve been forced to cancel it because of the spillage and TAFI has had to try and reschedule it on a river and at a time still to be decided – it’s hugely disappointing,” he said.

“We don’t know the full extent of the kill and how many exactly have died – we know it’s at least 5,000 but it’s devastating news because all fish have been wiped out for at least five kilometres.

“It looks like some sort of chemical spill and it’s killed not just fish life but also fly life so it’s going to have a serious impact on the chances of fish recolonising the river if they have no food.

“We still don’t know the full extent … there were trout gasping for air well downstream yesterday,” Mr Dennehy said.