OCSC was appointed by Louth County Council to undertake the design of the restoration of the Obelisk Bridge, a historical structure which spans the River Boyne approximately 5 km west of Drogheda. The bridge is protected under the Planning and Development Act 2000 due to its significance within both the Battle of The Boyne Battlefield Site and the Brú na Bóinne UNESCO World Heritage Site. OCSC tackled the project with a multi-faceted approach that included comprehensive surveys, thorough testing, and design work to ensure the conservation and rehabilitation of the bridge closely mirrored its original design. Their meticulous adherence to statutory obligations covered the bridge’s protective status, archaeological and heritage considerations, and environmental conditions. OCSC’s responsibilities ranged from identifying the best refurbishment options to managing the planning process, providing tender documentation, and executing the tender assessment. Their appointment included resident engineer services throughout the construction stage. The refurbishment of the Obelisk Bridge included the following works:

1. The replacement of the corroded wrought iron elements in the lattice truss, cross-girders and connections.
2. The replacement of the concrete deck slab.
3. The installation of a drainage system.
4. The refurbishment of the existing bearings.
5. The deconstruction and re-build of masonry abutment towers and approach walls.
6. Installation of a protective paint system to all steelwork.
6. Repointing of all masonry.
7. Installation of a vehicle restraint system.

As the bridge is located in a Special Area of Conservation, the construction works were entirely encapsulated to prevent are debris entering the watercourse below. The project’s culmination lies in the construction of the planned works, always with an eye on OCSC’s commitment to enhanced longevity and safety of this prestigious structure.

The launch of the refurbishment of the Drogheda Viaduct was held Monday 07th December 2015 in the D-Hotel in Drogheda, with Ministers Paschal Donohoe T.D. (Minister for Transport, Tourism and Sport) and Michelle McIlveen MLA (Minister for Regional Development) in attendance. The project was funded by the Special EU Programmes Body. The overall Drogheda Viaduct refurbishment works included the installation of 1,800m2 of new deck waterproofing, the application of 15,000m2 of a new paint protection system through the use of 4,500m2 of hanging scaffold and encapsulation, the replacement of 8 no. bridge bearings, steelwork repairs requiring the replacement of 14,000 rivets and 25,000kg of new steelwork. Essential track work was also carried out through the installation of 500m of new railway track, installing 850 new sleepers and 850m3 of new railway ballast. The refurbishment of this iconic structure also involved the installation of a new multi-coloured high power LED lighting scheme co-funded by Louth County Council.

O’Connor Sutton Cronin were responsible for the Contract management through the provision of a Resident Engineer from the Civil Section for the Painting and Scaffolding Contract. This 14 month contract was carried out in parallel with additional contracts for the steelwork repair works and bearing replacement by Irish Rails Bridge gang, completion of the track works by the permanent way staff and installation of the new multi-coloured high power LED lighting scheme by Global Rail. As these parallel Contracts would require access from the hanging scaffold provided under the painting and scaffolding works contract OCSC were also required to co-ordinate the works between each of the contracts to ensure all works were completed on schedule by November 2015.