Shannon-Dublin pipe scheme: Could it cause the river to dry up?

Locals fear the project may push the river to the edge amid an increased drought risk

Dublin’s water supply system has mains that are so ancient that not updating them is not an option, and yet the city is served by an abundance of high-quality water.

Twice as much water is produced daily than is actually needed by consumers.

On paper, water volumes should be more than enough to supply the future needs of a dynamic, growing city, but a combination of drought increasingly linked to climate disruption, rising demand and population growth will soon put supplies on a knife edge.

The proposal to extract water from the Shannon and pipe it to Dublin to serve 40 per cent of the country’s population prompts conflicting reaction.


Its proponents say it would provide a long-term solution to the eastern region’s current difficulties and emerging risk of disrupted supply. It opponents say it is unnecessary and will add to the vulnerabilities of the Shannon and Lough Derg, while not solving a leakage problem that is triple the average rate in western Europe.

You will soon be able to walk across the Shannon in your shoes

For dairy farmer Liam Minehan, whose farm is at Puckane, Co Tipperary, close to Lough Derg, "it's all down to do you believe it's necessary or not".

He says it is not necessary and is being favoured over other tangible solutions, which were brushed aside. And yet does not solve Dublin’s exceptional leakage problems, he argues. “A dismal pipe replacement rate of 0.3 per cent was achieved last year; worse than promised.”

He admits his opposition is primarily due to a pipeline that would quickly make his dairy business unviable, but he is also deeply worried about potential consequences for the Shannon. This prompted him to stand in the European Election in Ireland South.


On the worst day of the drought last year, Dubliners consumed 315 million litres of water while 300 million litres was lost due to leakages when the city was close to its limits in capacity to deliver.

Mr Minehan cites the case of Temple Bar, where the city's worst leaks are – in 80 per cent of pipes. There are 200-year-old pipes three metres under the ground, but Irish Water "are afraid to replace the pipes on the basis of disruption to businesses".

He contends a programme of replacing rather than fixing the pipes, which would be easily done by installing insulated pipes a metre under the surface. “It doesn’t make sense, spending €1.6 billion-plus on a pipeline, when businesses would have a reduced footfall of just a few weeks in getting the work done.”

The events of last year’s prolonged drought should put paid to any notion of taking water from the Shannon on the basis of a dramatic reduction in river flows.

Under legislation relating to the Ardnacrusha hydro-power plant, the ESB is required by law to ensure 10 cubic metres per second to flow down the natural channel of the river. During the drought it had to turn off the plant in an attempt to maintain flow on the river for several weeks, he claims. "My understanding is that did not reach the required flow."

With such droughts, “you will soon be able to walk across the Shannon in your shoes,” Mr Minehan predicts. This has to be factored in given the scale of extraction envisaged. There is a move to extract 1.5 cubic metres per second from Lough Ree to serve Athlone and Mullingar, while the pipeline to Dublin will extract at four cubic metres per second.

His family has farmed for four generations, yet its dairy business could be wiped out overnight as the pipeline would cut through its fragmented holding, making milking a large herd close to impossible.

His frustration is such that once planning permission is submitted, opposition will be scaled up through the courts in Ireland and Europe.

The Old River Shannon Trust, which monitors the river, posted on its Facebook page at the height of the 2018 drought that the Shannon at Curraghour Falls in Limerick city had been reduced to a relative trickle, “due to the extreme drought and that there had has been no hydroelectric generation at Ardnacrusha power station in two weeks as the water has run out”.

“If the Dublin pipeline was already built flows would be circa 40 per cent less than this – and the river would be at a real risk of drying up. Just 11 cubic metres of water per second is currently being released from Lough Derg – yet Irish Water are planning to take 4 cubic metres per second,” it said.

“This is not a sustainable proposal when droughts like this current one are factored in. Once the scheme is in place, the abstraction will be all year round 24/7, no matter what climate change brings.”


Professor of economics at DCU Edgar Morgenroth says increasing supply when there is a big leakage problem is not an efficient way to use a scarce resource, and underlines the importance of the Shannon in a different context.

“I have always made the point that [Dublin’s] leakage levels should be reduced significantly first. Another thing I doubt was done properly is to consider alternatives. I think they looked at desalination but they did not look at consolidating water resources across the wider region.

“The original analysis was done pre-Irish Water days, so that might explain why the wider resources were not considered but now with Irish Water in existence there is scope to link up different networks and exploit excess capacity elsewhere.”

Sinn Féin TD Eoin Ó Broin, a member of the Oireachtas Committee on Housing, Planning and Local Government, believes Dublin urgently needs a new water source.

Going to the Shannon makes an awful lot of sense and can be justified environmentally and ecologically, but with a 40 per cent leakage in the capital it fails to address another acute problem, so under current circumstances “40 per cent of what you bring from the Shannon will be lost”.

“Irish Water have yet to satisfactorily explain why it’s not accelerating its leakage programme, given what’s being achieved elsewhere, notably in London,” Mr Ó Broin says.

“I have yet to be convinced on the Shannon project. This is, firstly, because of the level of leakage in Dublin. I don’t understand why there is not an increased allocation to address this.”

Taking water from the Shannon and losing 50 per cent of it is ludicrous

He would like to see evidence on whether aquifers in the wider Dublin region are in a position to supply some of Dublin’s needs. The city has had an ongoing problem for 20 years that has to be faced up to, while extraction legislation needs to be published as a matter of urgency. “We need to know how much is being extracted by big business and farmers.”

He also has concerns about the cost of the project. At in excess of €1.3 billion, it was considered the largest infrastructural project ever undertaken by the State, until what has emerged on the national children’s hospital (NCH).

Added to that, he has concerns about the way the utility is constituted, in that it is “not subject to sufficient democratic accountability and scrutiny”. On that basis he favours bringing the utility back into State ownership.

Irish Water should be made a standalone non-commercial semi-State company, which would allow the Minister for Housing and the Oireachtas oversight, “to allow us ensure what’s happening with the NCH does not happen with this project”. In that respect, the committee would play a critical role.

Chartered hydrologist Shane Bennet of SM Bennet & Co in Rosmeen, Co Meath, is not in favour of the pipeline though he remains open to the possibility of being convinced. As an engineer familiar with major construction projects – and the menace of burst pipes in Dublin – he sees the need to carefully evaluate the project at this point, "when you look at how the children's hospital project has ended up".


London has reduced its leakage to less than 20 per cent, along with diversifying its water sources: some comes from surface water, some from groundwater and some from desalination of water taken from the Thames estuary.

While Dublin does not have shortages at most times of the year, during summer and drought periods it can quickly become an issue, he warns.

He believes the operation and maintenance of the pipeline would be costly when surface water storage and groundwater sources are an option, the latter especially providing a considerably degree of protection.

There is a vulnerability at the height of summer, as past incidents with the Poulaphouca water supply and in the lower Boyne have shown, while “world events” such as volcanic activity can pose a separate threat due to reliance on surface water.

Mr Bennet believes the Shannon is vulnerable, even to an isolated incident such as a pig slurry tank bursting its banks or simply the spreading of slurry too close to the water’s edge. Lough Derg has had a eutrophication problem in recent years, with excessive run-off of nutrients into the water causing a dense plant life growth.

Groundwater plus desalination adds up to much more modest cost, and that needs to be thoroughly explored because, as it stands, the project is “a bit of a white elephant with huge maintenance costs”, Mr Bennet says.

On dealing with leakages, he accepts it is problematic to hold up traffic for lengthy periods, but points out that the Luas was completed and London replaced its Victorian pipes because “needs must”. As it stands, “taking water from the Shannon and losing 50 per cent of it is ludicrous”, he adds.

Tomorrow: The response of Irish Water on Dublin’s water crisis and how the Shannon pipeline project was evaluated

Kevin O'Sullivan

Kevin O'Sullivan

Kevin O'Sullivan is Environment and Science Editor and former editor of The Irish Times