Roughan & O’Donovan undertook the role of Transport Infrastructure Ireland's Site Representative for the construction and handover stages of the upgrade of 24km of the M50 motorway from existing 2-lane carriageway to 3-lane motorway.
The consultancy services contract was the first national roads scheme let under the DPER Standard Conditions of Engagement.
In addition to widening the M50 carriageway from 2 to 3 lanes, the scheme also involved:
- Major upgrades of the junctions at the M1, N2 and N3 from their current grade separated junction type to free flow or partially free interchanges
- Upgrade works to the other junctions at Ballymun, Ballymount, N81, Scholarstown and Sandyford
- The provision of auxiliary lanes between the M1 and N3 junctions and between the Ballymount and Scholarstown junctions
- 70 Principal Structures including new bridges, retaining walls and upgrades to existing bridges
- Significant traffic management of the existing M50 where traffic volumes ranged between 70,000 to 120,000 AADT
- Installation of overhead sign gantries and new signage
- Upgrades to safety barriers, lighting, drainage and noise barriers
We undertook the technical review of all design, temporary works and construction submissions from the PPP Company. In all, we reviewed over 1,450 design packages and 2,300 non-design related submissions during the contract.
Roughan & O’Donovan was involved in the 3 separate construction contracts under which the upgrade was carried out.
Contract 1 was for the 8km section of road between Junction 7 and Junction 10 and was executed for South Dublin County Council under a design-build contract.
We worked at the tender stage of the contract as designer with AECOM for Clonmel-Laing O’Rourke. We carried out the CAT 3 check of the Monastery Road bow-string arch bridge for Ferrovial.
Contract 2 was for the upgrade of 24km of motorway between Junction 3 and 6 and between Junction 10 and 14 and the operation and maintenance of the full M50 motorway from Junction 3 to Junction 17 for 35 years.
We undertook the construction monitoring and contract administration for this contract.
Contract 3 was for the section of the motorway between Junction 6 and Junction 7 and was undertaken as a design-build contract by Jons Civil Engineering Ltd.
We were engaged by Jons as their designer for the contract and also provided the designer’s site representatives for supervision and certification of construction.