Nicholas O’Dwyer is proud to have played a key role in the successful delivery of the River Wad Phase 1B Flood Relief Scheme, a landmark €3.8 million project delivered in partnership with the Office of Public Works (OPW) and Dublin City Council (DCC).

Officially announced in July 2026, the scheme provides enhanced flood protection for residential and commercial properties in Clontarf, helping to safeguard the community against future flood events and strengthening local climate resilience.

The River Wad catchment has experienced significant flooding in the past, leading to the development of a phased flood alleviation programme. Phase 1B forms a critical part of this wider strategy and, together with the previously completed Phase 1A scheme, now protects a total of 112 properties along the river corridor.

Nicholas O’Dwyer’s Role

Nicholas O’Dwyer provided multidisciplinary services across both the Howth Road Tunnel and Clontarf Outfall Scheme projects, including:

  • Design and hydraulic modelling
  • Project Supervisor Design Process (PSDP) services
  • Employer’s Representative services
  • Resident Engineer services throughout construction

Howth Road Tunnel

Constructed by Ward & Burke Construction Ltd, the Howth Road Tunnel involved the delivery of a new tunnelled culvert beneath the busy Howth Road using advanced microtunnelling techniques. This innovative solution increased conveyance capacity while minimising disruption to the surrounding environment and local community.

Key elements of the project included:

  • Construction of upstream and downstream connection shafts and chambers
  • Permanent flow management infrastructure to split and reunite river flows
  • Utility diversions and temporary works
  • Construction compounds and environmental protection measures
  • Preparation and completion of the project Safety File

The new tunnel forms a vital link within the flood relief system, improving the river’s ability to safely convey floodwaters during severe storm events.

Clontarf Outfall Scheme

Delivered by Triur Construction Ltd, the Clontarf Outfall Scheme focused on improving the capacity and resilience of the downstream section of the existing culverted River Wad where it discharges into Dublin Bay.

The works included:

  • Construction of an additional precast concrete outfall culvert connected via a new interception chamber
  • Delivery of a new sea outfall structure
  • Sealing of vulnerable manholes susceptible to tidal surcharge
  • Rehabilitation and repair of the existing sea outfall

These interventions significantly reduce the risk of tidal influences contributing to flood conditions within the catchment and strengthen the overall performance of the flood relief system.

Building Climate Resilience

Nicholas O’Dwyer is delighted to have contributed to a project that delivers lasting benefits for the Clontarf community and demonstrates the value of collaboration between clients, contractors and stakeholders in delivering resilient infrastructure for future generations.

The successful completion of the River Wad Phase 1B Flood Relief Scheme represents an important step in protecting homes, businesses and critical infrastructure from flooding while supporting long-term climate adaptation across the area.