Aerial view of the M50 motorway and surrounding area; Aerial view of the M50 motorway and surrounding area;

M50 Widening Scheme, Dublin

The largest urban motorway project in Ireland

The M50 is the largest urban motorway project constructed in Ireland. It included major road widening and improvement schemes along the whole of the country. Arup carried out the civil engineering, the infrastructure design and the transport consulting services and developed a procurement strategy with a range of clients, procured the various tenders, supervised the construction and generally administered contracts.

Congestion problems

Prior to Arup’s involvement in the 42km long upgrade, the M50 easily rivalled London’s M25 status as the most congested motorway in Europe. 

Choked by insufficient capacity, proximity of interchanges and an inadequate toll collection system, there was a general consensus between Road Authorities, politicians and the travelling public that ‘Something must be done’.

However, having little experience with major road widening or significant route capacity improvement, the Irish National Roads Authority tendered a major commission to identify, develop, statutorily procure and deliver large scale improvements to the full route and all of the existing interchanges.

Aerial view of the Red Cow Interchange Aerial view of the Red Cow Interchange
One of the first projects on which D&B and PPP Contract Documents were utilised.

Free-flowing route

The ultimate goal was to create a world class free-flowing route around the city, providing an essential hub to the planned substantial upgrade of the country’s system of radial strategic routes. Arup won the tender in 2004 and immediately set about developing a scheme which would provide the final desired outcome with the minimum cost and disruption. A successful and ultimately much admired design concept was developed, optimising the available land.

The next important hurdle to overcome was the development of an environmental approach for the entire route which would deliver real sustainability, protect existing environmental assets and minimise disruption to adjacent residential and commercial properties. Arup met and beat these challenges through an enormous effort from multiple disciplines, including environmental, highway, bridge and transport engineering.