The current studies, in relation to the long-term water supply needs of the Dublin Region, have been underway since 2004. Over the intervening period, two phases of formal public consultation have taken place (2006 & 2008/09) under the Strategic Environmental Assessment (SEA) process, regarding potential new source options for meeting long-term water supply needs. The (2008) draft Plan and Environmental Reports, involving 10 potential new water supply options, were tabled for public consultation under the SEA process from November 2008 to Feb / March 2009. Consultations with stakeholders during this period were extensive and feedback from the process has now been incorporated, as appropriate, into the current recommendations.

Current supply / demand balance in the Dublin Region is on a knife edge with little or no spare capacity. Planned expansion of existing water treatment plants (Ballymore Eustace & Leixlip) will enable demand growth to be met in the short term (for a limited period) but the expanded water treatment facilities will not provide sufficient headroom to ensure satisfactory long-term ‘security of supply’. Additional capacity is required to cope with potential plant outages, infrastructure failure, new ‘wet’ industries, the effects of extended dry periods or icy conditions (as witnessed in January 2010 when severe water shortages occurred for prolonged periods) causing increased leakage in the old cast iron mains.

Over the 2004 – 2010 period, a range of demand scenarios were developed to assess the likely timing of supply requirements from a new source. The planned growth objectives in the Dublin & Mid-East Regions (Greater Dublin Area) as envisaged in the (2010 – 2022) Regional Planning Guidelines and National Spatial Strategy form the basis for estimating the extent of water availability which must be provided in order to sustain the economic growth targets and associated domestic and non-domestic demands.

Because of the lengthy time periods involved in Planning, Procurement and Construction processes, the study report, which has been submitted to Dublin City Council (DCC) / Department of the Environment Heritage & Local Government (DEHLG) in July 2010, recommends that planning for a new source, to be available by 2020 latest, should commence now, with the objective of satisfying demands up to 2040 and beyond. The objective would be for a plant capable of providing up to 350 million litres of water per day.

The recommended option involves abstraction of water from Northern side of Lough Derg on the River Shannon just North of Limerick and pumping of raw water during high flow periods into large scale storage lakes in Bord Na Móna owned former / cutaway bogs in the Midlands (Garryhinch, Co Offaly). From there, treatment of water adjacent to the raw water storage lakes and treated water will be pumped to the Dublin Region and to the Midland Counties. In this way, the new supply would be sustainable throughout the year and would meet the strategic needs of both the Dublin and Mid-East regions of Ireland, irrespective of climatic conditions.

The project would cost an estimated €500m and would comprise, in addition to the raw water storage lakes, some 115km of twin pipeline (1,200 – 1,400mm diameter), a water treatment plant to treat 4 cubic metres per second to EU drinking water standards, along with associated pumping plant and treated water storage reservoirs.

The raw water storage lakes have the potential to be developed as an eco-tourism attraction and have been modelled on man-made lakes in East Anglia (Rutland) operated by Anglian Water and eco-tourism facilities in Boora operated by Bord Na Móna.

Recommended Option

The water storage lakes will contain a minimum 2 month’s average supply of water for the Dublin, Mid East & Midland Regions. Availability of this stored water enables abstractions of water (from Lough Derg’s storage) to be matched to Shannon flows into Lough Derg. The lakes will be filled during Shannon high flow periods and will be used during Shannon low flow periods to provide the required water supply volumes. In low flow periods, abstractions will be minimised or ceased entirely when flow conditions warrant. Water levels in Lough Derg will not be affected by the water abstraction proposals, as ESB hydroelectric operations at Ardnacrusha manage Lough Derg water levels within agreed upper and lower limits (approx 18 inches apart). Environmental assessments to date have identified that the outline water supply scheme, as proposed, is sustainable. The next stage of assessment (Environmental Impact Assessment – EIA), which is required for the formal planning process involving An Bord Pleanála, will scope the proposed abstraction regime & operation of associated raw water storage in greater detail. The EIA process will also involve further consultations with all relevant stakeholders.

Next Steps

• Stakeholder Briefings – July to October 2010
• Agree Scope of EIA (Stakeholders & An Bord Pleanála)
• Adoption of (2010) Draft Plan by Local Authorities
• Publish Adopted Plan and SEA Statement (Close out SEA process)
• Preparation of EIA (Planning Application) 

For further information on the project, visit www.watersupplyproject-dublinregion.ie

Contact:
Gerry Geoghegan, Project Manager
T:+353 (0)1 4882900
E: gerry.geoghegan@rpsgroup.com