Maeve O'Connell (Dublin Rathdown, Fine Gael)
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353. To ask the Minister for Public Expenditure and Reform to report on how often the flood defence systems along the Dodder River are assessed to ensure they meet the required capacity. [25192/25]

Kevin Moran (Longford-Westmeath, Independent)
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The current status of relevant flood relief schemes is set out below (Dodder Tidal Phase 1, Dodder Phase 2C, 2D, 2E, and Dodder Phase 3), as well as other relevant information.

Dodder Tidal Phase 1 Flood Relief Scheme

The Dodder Tidal Flood Relief Scheme was initiated in 2003 following a major tidal flooding event in February 2002. Emergency construction started immediately following this tidal flooding event and continued with new flood walls adjacent to Stella Gardens in 2003 and 2004. From September 2007 to 2013, flood alleviation works from Ringsend Bridge to Newbridge on the Dodder Estuary were constructed following Part 8 planning permission. The Scheme, which comprises mainly of flood defence walls and embankments, provides protection against a 200-Year flood (0.5% Annual Exceedance Probability) for an estimated 1,000 businesses and homes in Dublin City from tidal flooding.

Dodder Phase 2C, 2D, 2E Flood Relief Scheme

The Dodder Phase 2 Flood Relief Scheme includes flood defence walls and embankments from Newbridge to Ballsbridge and upstream of these to the Smurfit weirs. The scheme provides protection against a 200-year flood (0.5% Annual Exceedance Probability) in the tidal reach and 100-year flood (1% Annual Exceedance Probability) in the reach above Ballsbridge against fluvial flooding with associated tidal influences. The Scheme was initiated in 2012, after major flooding in August 1986 and October 2011, and began construction in 2012. The scheme was completed in 2023 and offers protection to 1,493 businesses and homes.

Operation and Maintenance of the completed schemes is led by Dublin City Council, and the Office of Public Works engages regularly with the Council regarding same. The Council carries out regular maintenance on vegetation, silt, and invasive species.

Dodder Phase 3 Flood Relief Scheme

Dublin City Council, in conjunction with the Office of Public Works and Dun Laoghaire-Rathdown County Council, are now advancing with Phase 3 of the River Dodder Flood Relief Scheme. Phase 3 is currently at Stage I (Scheme Development and Preliminary Design).

Catchment Flood Risk Assessment and Management (CFRAM) Programme

In 2018, the OPW completed the largest study of flood risk ever undertaken by the State: the Catchment-based Flood Risk Assessment and Management (CFRAM) Programme. The CFRAM Programme studied 80% of Ireland’s primary flood risk and identified solutions that can protect over 95% of that risk. Some 150 new and additional flood relief schemes were identified through this Programme.

The CFRAM mapping carried out by the OPW was originally a point-in-time study, completed as part of a national programme to assess flood risk in 300 communities.

However, the OPW acknowledges that flood risk evolves over time due to factors like climate change, urban development, and land use changes.

To address this, the OPW has an ongoing programme of work to reassess and update flood risk information across the country. This includes:

• Monitoring and updating flood maps and models as needed.
• Maintaining compliance with the EU Floods Directive, which requires member states to review and update flood risk assessments and maps every six years.