How many construction workers does it take to build a road? 

Roads get us from A to B. We all know that. But it’s fascinating to consider the work that goes into creating them. 

The £135m Caernarfon and Bontnewydd bypass is one of the largest infrastructure projects being carried out in North Wales.  

Cars will be welcomed onto this new stretch of the A487 in early 2022 - the result of more than 14 years of work. So, what has to happen before a new road can be built?  

Why build a new road? 

First, the need has to be there. Way back in 2008, local authorities and planning officers proposed the development of a bypass to: 

  • Reduce traffic and lower journey times 
  • Improve connections 
  • Lower noise and air pollution in urban areas
  • Reduce collisions. 

Following a long process of appraisals and public consultations, the bypass was agreed upon. Contractors Balfour Beatty and Jones Brothers were appointed to oversee the development, and turn it from a vision into a reality. 

Not just tarmac 

Site investigations and surveys were carried out, to help highway engineers design and plan the bypass. In addition to 9.8km of new single and two-lane carriageway, the development involves the construction of 22 structures such as culverts and seven bridges, including a crossing over the Welsh Highland Railway and two viaducts. 

Boosting the local economy  

As well as improving travel options, the bypass is benefiting the Welsh economy. Over 90% of the workforce involved are Welsh or live in Wales, and 75% of the scheme’s costs are being spent with local suppliers. 

Spotlight on some of the jobs involved: 

 Hundreds of professionals in all sorts of roles, from cost consultants to designers, highways maintenance technicians to legal advisors and more are involved with this landmark project. How have they influenced the build? We’ve picked a few professions to look at more closely.  


As earthworks got underway, a bronze age canoe was uncovered by archaeologists on site and taken away to be conserved. Land surveyors’ reports led them to excavate a large section of Roman road and confirmed an ancient route between historic forts in North Wales.  


30 ecologists surveyed the area to identify wildlife at risk from the development. They recommended the installation of culverts and pipes and realignment of water courses to protect the habits of otters, water voles, bats and fish. Whilst trees needed to be felled along the new route, ecologists ensured that more vegetation was planted than removed, introducing 13 new hectares of woodland, 23km of hedgerows and 30 hectares of species-rich grassland.  

Transport modellers 

Transport modellers have been key to this project. Back in 2008 they predicted that, if work didn’t go forwards, traffic flow on the original A487 would exponentially increase, causing longer queues and delays at key roundabouts and junctions, and unsafe volumes of vehicles passing through towns. 

Plant operators 

Machine drivers have used bulldozers, 360 excavators and dumper trucks to clear and level land, and to transport heavy materials to and from site. They can transform a landscape in a very short time and have been integral to this large scale construction project. 

Apprentices and recent graduates 

More than 14 apprentices have been involved, learning valuable skills and training alongside experienced professionals on this major project. Contractors have employed graduates to gain experience on site and assist the site team in engineering, administration and health and safety roles, as they start their careers.  

Considering a job in construction?

Wondering whether a role in construction would suit you? Use our Career Explorer to discover jobs in the industry that match your skills and interests. 

If you have any queries, get in touch with us on our social media: 

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