McCabe Group were pleased to be enlisted by Cavan County Council as main contractors to complete the restoration and conservation works of Dunancory Bridge, Virginia, Co.Cavan in 2020.

Malachy Walsh and Partners were appointed as consultant Architects whom alongside Cavan County Council designed and engineered the infrastructure works across the project. Work commenced in August 2020 on the project. The bridge which underwent its first survey and trial holes almost 70 years ago is a vital piece of infrastructure as the main link from Edgeworthstown to Dublin, with over 9000 vehicles passing over the bridge per day.

This bridge project had many specific requirements including the complete restoration of the existing bridge, the formation of the arch barrel and the construction of a new concrete independent structure to widen the bridge to better accommodate pedestrians and vehicles.

A key initial requirement of this project given its history was the environmental consideration that had to be given to the bridge and surrounding area. An Appropriate Assessment (AA) had to be carried out before building could commence. The results of the AA highlighted that Bat, Otter & Dipper wildlife needed to be protected, while works were ongoing. Once the environmental analysis was completed excavation works commenced. During this process, the McCabe Group team were faced with a major challenge on the project as the existing structure began to weaken and was deemed unsafe for road user usage and pedestrians. Unfortunately, due to this unforeseen issue, a road diversion was put in place for 12 weeks to ensure the bridge was appropriately restored for public use.

The second phase of the project involved the construction of the new abutments and arch barrels. As part of this McCabe Group were required to divert the fast-flowing river water by creating a Cofferdam system. The cofferdam system would enable McCabe Group to carry out the installation of the new concrete foundations and rising walls to the depth of 5m. Timber formwork was then installed on the extension of the arch barrels along with 20 tonnes of rebar steel and 600mm of concrete. This required a significant volume of propping which was designed and supplied by RMD KWIKFORM. The new limestone arch included Vossler keystones. 

The third phase of the reconstruction was securing the new parapet wall into position. Kilkenny limestone capping was used for the parapet walls to match the existing arch. A new independent concrete structure was erected to allow movement to the existing bridge as it was a complete limestone structure, improving the durability and strength of the bridge for years to come.

The final phase of the project involved the laying of new road surfaces and pedestrian footpaths which included drainage kerbs with petrol/oil inceptors. The new footpaths were constructed to join the existing residential estates and to join the newly refurbished Deerpark Forest. The road surfaces on both junctions were re-aligned along with all communication services, and water services that were installed underground. New decorative and standard public lighting was installed to coordinate with the town’s public lighting requirements