The cost of the water supply pipeline from the river Shannon to the Greater Dublin Area could exceed €10 billion in a worst-case risk scenario, according to correspondence submitted by the Department of Housing to the Public Accounts Committee (PAC).
The proposed water supply project for the eastern and midlands region will take water from the lower river Shannon at the Parteen Basin in Co Tipperary, treat it at a plant in nearby Birdhill, and pipe it 170km to Peamount in southwest Co Dublin.
In correspondence to the PAC, the secretary general of the department, Graham Doyle, said risk analysis of the project had produced a wide range of projected costs, running from €3.3 billion up to €10.4 billion “depending on the confidence level of risk applied”.
Mr Doyle said, however, that for the preliminary business case, the State’s water utility company, Uisce Éireann, is using a preliminary indicative estimate range of €4.6 billion to €6 billion.
The estimated cost of the project, which will not complete the planning process until the second half of 2027, has increased substantially over the years.
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In his correspondence to the committee Mr Doyle outlined how the initial estimates were between €800 million and €1.4 billion.
“However, following the adoption of a more mature approach to risk identification, additional project design and development and provision for inflation at the time, a revised preliminary indicative estimate range of between €1.9 billion and €2.4 billion was adopted in 2020,” he wrote.
Much of this increase was attributable to great requirements for contingencies, as well as design changes, and a higher inflationary environment.
Mr Doyle said that, at present, the project base cost estimate, excluding any contingency allowances, is €3.025 billion.
“International experience demonstrates that in practice, all large projects have numerous risk factors that can impact on their delivery,” he stated.
“For this reason, a risk allowance is added to the base cost of the project to address the cost implications of such risks potentially materialising.”
A total of €74 million has been authorised to Uisce Éireann to spend on the project to date. It is currently seeking an additional €88.6 million to cover all activities between now and the third quarter of 2007, when planning approval is expected.
Mr Doyle outlined in the correspondence that if no additional supply was provided to the Great Dublin area, the deficit in the region’s water supply would have severe consequences.
“Many water sources in the region would be at capacity by the late 2020s and would be unable to cater for new residential and commercial connections. Existing business and household customers would experience more frequent water supply restrictions and there would be significant negative impacts on society and on the region’s economy.”
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He said Dublin was over reliant on the river Liffey, which provided 85 per cent of the capital’s water. A desalination plant in Dublin Bay – that would treat seawater and make it potable – was one of the options examined to address future water supply for Dublin. But the proposal to extract water from the Parteen basin was chosen as the optimal source of supply.
Campaign groups in Co Tipperary oppose the project. They claim it will damage thousands of hectares of agricultural land, and will also have a negative ecological impact on the river Shannon.
