Project Summary
Coffey delivered the construction of a 6.8 km dual carriageway linking Williamstown Road with the N25. The works included five new roundabouts, major reinforced concrete structures, drainage, lighting, and comprehensive earthworks. Key challenges included building a 5 m high embankment through Kilbarry Bog and managing traffic safely while maintaining access for vehicles, cyclists, and pedestrians. The project was completed on time and provided a safe, efficient, and durable new road link that improves connectivity in the region.
Project Description
This project involved the construction of approximately 6.8 km of new dual carriageway, along with sections of single carriageway and five new roundabouts. Works included major earthworks, pavement construction, drainage, kerbing, landscaping, services ducts, and reinforced concrete structures such as the Lacken Road Bridge and St. John’s River culvert.
A 5 m high embankment was built through Kilbarry Bog at the St. John’s River crossing, requiring careful ground treatment to ensure stability and protect the environment. The project also involved removing existing road lighting and installing new lighting across the scheme, including at roundabouts and approaches.
Traffic management was a key part of the works, ensuring vehicles, cyclists, and pedestrians could continue to use the area safely during construction.
Scope of Works
The works included:
- Construction of approximately 6.8 km of dual carriageway and associated single carriageway sections.
- Development of five new at-grade roundabouts.
- Construction of a 5 m high embankment through Kilbarry Bog with ground stabilisation measures.
- Delivery of major reinforced concrete structures including the Lacken Road Bridge and St. John’s River culvert.
- Installation and removal of road lighting across the site, including at roundabouts and approaches.
- Mass earthworks, deep excavations, high fill embankments and pavement construction.
- Drainage, kerbing, landscaping, pedestrian crossings, and cycle tracks.
- Installation of traffic signs, road markings, fencing, and safety barriers.
- Environmental mitigation works to protect sensitive habitats.
- Accommodation works and service diversions.
- Comprehensive traffic management for vehicles, cyclists, and pedestrians.
Technical Highlights
- Constructed a 6.8 km dual carriageway linking Williamstown Road with the N25.
- Delivered five new roundabouts to improve traffic flow and safety.
- Completed the 3-span Lacken Road Bridge and St. John’s River culvert.
- Installed new lighting across multiple junctions and approaches.
- Executed mass earthworks and complex ground treatment in Kilbarry Bog.
- Implemented traffic management to maintain safe movement for all road users.
Added Value
- Enhanced regional connectivity with a durable and efficient new road link.
- Strengthened safety with improved road layout, lighting, and crossings.
- Integrated infrastructure for vehicles, cyclists, and pedestrians.
- Applied modern construction methods to balance technical and environmental challenges.
Environmental, Safety or Community
- Careful ground treatment and embankment construction through Kilbarry Bog to safeguard the environment.
- Traffic management strategies ensured safety for all road users during construction.
- Close collaboration with local authorities to minimise disruption and maintain community access.
- Landscaping and environmental mitigation works delivered long-term ecological benefits.
To learn more about Coffey’s work in active travel and urban infrastructure, or to discuss future opportunities, please contact us at 091 844356 or info@coffeygroup.com.
