UISCE ÉIREANN HAS been convicted in the District Court of a single charge in relation to a chemical spill on the River Allow in north Cork in June 2024 which led to a major fish kill along an 8km stretch of the river.

The water authority pleaded guilty to a single charge under the Fisheries (Consolidation) Act, 1959 of permitting or causing deleterious matter to fall into waters of the river.

Solicitor Vincent Coakley for Inland Fisheries Ireland (IFI) said that the incident occurred at the Freemount Water Treatment Plant on or shortly before Sunday, 9 June 2024.

Giving evidence IFI Senior Environmental Officer Andrew Gillespie said that he was called by Cork County Council staff who were on duty at the plant and informed there had been an incident. He told the court that he arrived at the plant at 3pm on 9 June.

Mr Gillespie said that there had been a chemical spill into the River Allow, a tributary of the River Blackwater and an important spawning ground and nursery for salmon and trout. He said that when he arrived a major cleanup operation was already underway.

Mr Gillespie said that a pipe running from a 13 cubic metre tank of Polyaluminium Chloride—an acidic solution used in the water treatment process—had failed and the chemical had leaked into the river via an adjacent drain. He said that the tank had about three cubic metres of the chemical in it at the time most of which had leaked out.

Mr Gillespie said that water samples were taken 10 meters downstream from the treatment plant, 2km downstream at Kilberrihert Bridge and 4km downstream at Johnsbridge as well as a base sample upstream from the treatment plant.

He told the court that a dark brown substance could be seen in the water near the treatment plant and hundreds of dead fish could be seen in the river. He said that as well as juvenile and large salmonids, large numbers of dead and dying lamprey were also observed, a fish that normally stays on the river bed. 

Mr Gillespie said that a thorough investigation was carried out which determined that the chemical spill had affected an 8km stretch of the River Allow over an area of 40,000 sq m.

He said that it was very difficult to determine the total number of fish killed but it was certainly in the “tens of thousands” extrapolating from a “conservative estimate” of one fish killed for every 2 sq m of the river affected. He added: “All we can say is that there were no dead fish upstream and there were no live fish down stream for 8km.”

Mr Gillepsie said that the water quality in the river had returned to normal “within a few days” but the long-term effects on the age and class distribution of fish populations could take several years to return to the way they were.

Aoife Sheehan BL for Uisce Éireann said that her client had been fully cooperative and had informed all relevant authorities as soon as the leak was discovered.

She said that Uisce Éireann was pleading guilty and had taken immediate remedial steps as soon as the spill was detected. She said the scale of the response reflected how seriously Uisce Éireann took such matters and that the event had had an impact on national policy regarding chemical storage.

Ms Sheehan told the court that the storage tank in question was fully bonded but investigations indicated that a pipe leading from it had been subject to a build up of heat that caused it to disintegrate causing the leak. She said that it was believed a valve had not opened while a pump was in operation which led to the temperature increase.

She said that a task force had been established to look at national policy to ensure a similar situation does not occur in the future. She added that the water supply from Freemount serves a population of 3,000 people and this was not compromised as a result of the leak.

Judge Colm Roberts said that he appreciated Uisce Éireann may not have the funding to carry out all the works it would like to but he said it was a “real concern” that the Freemount plant was audited before the leak occurred. He said: “It’s to do with having the right plan and the right maintenance,” and added, “they stepped up to the plate but it was really a case of closing the stable door. It’s often the simple things that don’t get done when you are dealing with organisational pressure.”

The court heard that Uisce Éireann had not been previously prosecuted in relation to the Freemount plant but there had been 18 prosecutions for “similar incidents” between 2015 and 2024.

Mr Coakley said that there were “a number of pending prosecutions” regarding Uisce Éireann. Judge Roberts said he was taking into consideration the guilty plea, the works in progress and the “legacy issues” and convicted and fined Uisce Éireann €3,500 with one month to pay, they were also ordered to pay €3,267 in legal costs.