Welsh Government


Infrastructure delivery

Contract Type

NEC3 Option C

The challenge – creating a dual carriageway through valley and mountain

Carillion took the lead on an important section of this improvement project for the A465 Heads of the Valley road – one of the major routes through Wales. The objective was to provide safer, more reliable journeys for road users while maximising economic benefit and legacy for the local community.  This was a highly complex heavy civil engineering project through urban and rural environments, with the added challenge of keeping the traffic flowing and access routes open for the community.

The solutions we created – detailed planning for a successful civil engineering scheme

Via early contractor involvement, we supported our client through the statutory processes from 2010, before we began the design and build of the 7.8km of new dual carriageway in January 2013. This stretch of road required four junctions, eight bridges, three underpasses, and six retaining walls up to 28m high. The complex geotechnical conditions required significant blasting work – more than a third of the 900,000 m3 earthworks was hard rock. It also included historic mine workings, thick peat and large volumes of surface and ground water runoff. All the materials were classified and processed for reuse using our own on-site facility.

Every stage of the project needed temporary works to maintain public and works access, from road diversions and closures to temporary river crossings. Many alternative routes were negotiated to create the best solution for the community, for safety and for efficiency. For example, while constructing the major embankment at Carno, the team, in looking for the best access for the 10,000+ vehicle movements, avoided using the existing narrow and busy public road and instead negotiated access through a disused industrial unit. We later recycled this 600m site road to form some of the 5.1km of permanent cycle track.

An innovative ‘light touch’ approach enabled client and contractors to work in the most productive way, to give the best value for money. Carillion used Building Information Modelling (BIM) to model and plan all aspects of the project. All the earthworks, drainage and pavement operations on site were controlled directly by GPS machine control using the planning model.  This offered a clear safety benefit, with fewer people working around machines, and demonstrated improved efficiency and quality. Full handover documentation was available within one month of completion.

Outcomes, benefits & social value – sensitive to the environment – and the budget

The project was completed on time and under budget in summer 2015. After a detailed review, we reduced the original scheme’s proposed disposal of 750,000m3 of surplus earthworks materials to zero – saving our client more than £15 million.

The project ran through the Brecon Beacons National Park at its eastern end as well as several designated sites, e.g. for ancient woodland and bats, plus seven Sites of Importance for Nature Conservation. After appropriate assessments, mitigation measures were agreed with all relevant bodies such as Natural Resources Wales. The regular Environmental Liaison Group Meetings will continue for five years after the completion of the project.

Replacing a planned viaduct with an earthwork reduced construction carbon by 10%. Junction improvements will save 18,304 tonnes of carbon over the first 15 years, offsetting approximately 35% of the carbon produced during construction.

Welsh Government has recognised Carillion for setting a new benchmark in adding value through delivery of extensive community benefits, helping to drive economic regeneration.

We made great efforts from the outset to engage with the local community and keep everyone informed through public meetings, roadshows, information days and newsletters, to making personal visits to 83 private landowners and 39 businesses before construction began. A website and social media were well-used throughout.

The project delivered 640 years of Welsh employment with an 85% Welsh workforce, exceeding the contractual target for New Entrant Trainee employment by over 20% and realising 84% of spend through Welsh based businesses. The project also delivered the UK’s first National Skills Academy on a highways scheme, raising the bar for future construction training. The project supported 27 apprenticeships including Carillion’s first Technical Apprentices in Civil Engineering (3) and Quantity Surveying (4).

To improve the future prospects of young people the team supported the implementation of South Wales’ first BITC Business Class Cluster, developing long-term partnerships between a number of schools and businesses in the Heads of the Valleys area. The team delivered over 100 activities involving over 4,100 pupils across 50 schools and colleges, including 155 weeks of work experience. The project also supported some 50 local community initiatives.


Welsh Government Seren Awards – Participation & Community Award (2012)

CITB Construction Ambassador Awards – S.E Wales Employer of the Year (2013)

Considerate Constructor Scheme – Bronze Award (2013)

Business in the Community Responsible Business Awards – ‘Wales Education Award’ (2014 and 2015)

Business in the Community Responsible Business Awards – ‘Inspiring Young Talent’ (2014 and 2015)

Considerate Constructor – Silver Award (2014)

Synchro Visual Planning Awards for Road and Bridges 2014

Constructing Excellence in Wales – Value Award (2015)

Tredegar Town Council Civic Award for work with the Community of Tredegar

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