An iron sludge discharge from a "no longer fit for purpose" water treatment plant operated by Uisce Éireann was the cause of an "ecological tragedy" that wiped out all fish life over a 2.6km river, a court has heard.

At Ennis District Court, judge Alec Gabbett fined Uisce Éireann the maximum fine allowed of €5,000 for each of the two pollution discharges from the Ballymacraven water plant near the north Clare town of Ennistymon on 2 May and 18 May last.

Before Judge Gabbett imposed the combined €10,000 fine, solicitor for Inland Fisheries Ireland (IFI) Dermot O’Donovan said that what occurred on the Ballymacraven River on 2 May last was “an ecological tragedy”.

Uisce Éireann has also agreed to pay IFI’s costs of €5,477 in connection with the fish kill.

In evidence, IFI fisheries environmental officer Jane Gilleran said that the discharge from the plant on 2 May resulted in “a very significant fish kill” with an estimated 2,000 dead fish.

Asked to outline the extent of the fish kill, Ms Gilleran said: "Everything below the water treatment plant in terms of fish was wiped out.”

Ms Gilleran said that the fish kill continued over a 2.6km stretch of the Ballymacraven River before it meets the confluence of the River Inagh downstream of the Falls Hotel in Ennistymon.

Suffocation

Ms Gilleran said that the vast majority of fish - including salmon, eels and trout - died from suffocation.

Ms Gilleran told Judge Gabbett: “You can see photos of dead fish with their mouths open and that would indicate suffocation. The iron sediment clogged their gills and kill[ed] them.”

Ms Gilleran told the court that the fish kills wiped out three age classes of salmon on the Ballymacraven River and she said “for the salmon, the river may never recover because we have lost the three age classes”.

She said: "If you lose all the salmon from a river, you don’t have a population to return to and it is a very small percentage of salmon that would stray back.

"We had salmon parr - and they would be returning to sea to feed and then come back to spawn and we had the salmon that were a year younger. And everything that would have spawned that previous winter - they would have been only to three to four centimetres in length and they would have been smothered in the gravel.”

Ms Gilleran also stated that quite mature eels up to 60cm in length that can live in lakes for 50 to 60 years of age were also victims in the fish kill.

She said: "Eels are critically endangered, so we have lost quite a significant population of eels. Our research department at HQ were amazed at the number of eels that were found dead is such a small river.”

Ms Gilleran said that the river had a heavy discolouration on 2 May from the discharge resulting in a rusty brown colour.

Ms Gilleran said that Ballymacraven is an older plant and was operating significantly above capacity.

The plant serves a population of almost 7,000 people in the wider north Clare area including Ennistymon, Lahinch, Kilfenora, Doolin, Fanore and Ballyvaughan.

Ms Gilleran said: "The EPA has said that it is operating 55% above capacity, but it is also undergoing works at the moment to increase capacity.

“There was not enough capacity at the plant for the sludge to settle and sludge builds up too high and reached a level and overflows to the river."

Ms Gilleran said that the plan has been on the remediation action list by Uisce Éireann for some time and the incident occurred during a bank holiday weekend when there was extra pressure on the plant with the population locally.

Alert

She said that the Ballymacraven plant takes water from the lake and cleans it and make keep it safe for human consumption.

Ms Gilleran said that on the dates, there was no system in place to alert people that there was a discharge, but there is now.

On behalf of Uisce Éireann, Aoife Sheehan BL told the court that “this was a very serious incident and Uisce Éireann takes its responsibilities very seriously and it is here to meet those charges”.

Ms Sheehan said: "There were a number of issues that unfortunately gave rise to the incident on 2 May, but it is important to note at the outset that fundamentally this is an old plant with old infrastructure, inadequate and no longer fit for purpose.

"That was recognised by Uisce Éireann who took over the running of the plant in 2014 and was one of the plants earmarked for major investment needed to upgrade.

"That investment has been made and the upgrade programme is an advanced stage," she said.

Drought

She said that "in terms of what happened on the day, it happened during intermittent drought in May. It was a bank holiday weekend and the demand for water was very high and that meant that the plant was treating a very high volume of water and a high volume of sulphate.

"The plant was already struggling to deal with capacity fundamentally ….and what we think happened overstretched the plant," she said.

Ms Sheehan said that an inspection of the plant "was carried out on the day in question and this didn’t raise any flags”.

Ms Sheehan said that Uisce Éireann has "a new operating procedure in place to prevent a recurrence of what went on”.

She said that the plant is now de-sludged five times a week, with 45t of sludge removed weekly.

She said that the upgrade works commenced in 2022 and are due to be complete in autumn of this year, representing a €7.5m investment.

She said that €3m has been invested in the residual treatment aspect of process that was the difficulty in this case.

Alarm

Ms Sheehan said that there are now electronic monitoring alarm systems in place to alert personnel if anything goes wrong as part of a comprehensive system designed to prevent recurrence.

Mr O’Donovan said that Uisce Éireann co-operated fully with the IFI investigation, but stated that, unfortunately, Uisce Éireann has a list of previous convictions "which is considerable”.

“Uisce Éireann has been convicted at Ballyshannon, Ballyshannon, Blackrock, Ballyshannon, Ballyshannon, Ballina, Monaghan, Cavan, Louth, Cavan, Cavan, Louth, Offaly, Wicklow, Tipperary, Cavan, Cavan, Cavan and Cork," he said.

Judge Gabbett said that, in fairness, Uisce Éireann had inherited all the legacy problems from county council-operated plants around the country and Mr O’Donovan agreed.

He said: "To be fair to Uisce Éireann, they do a reasonably good job and everyone who has potable water has finer water than anywhere else in the world."

Judge Gabbett said that Uisce Éireann "has a legacy problem that they have to deal with and, unfortunately, the fish are the victims here and I can’t get a victim impact statement from the poor fish”.