Costain and Mott MacDonald appointed to Stonehenge road and tunnel scheme

A303 traffic at the Stonehenge World Heritage Site.

National Highways has appointed a Costain and Mott MacDonald joint venture as Delivery Assurance Partner for the A303 Stonehenge Improvements Scheme. 

The project will manage design and construction of a new dual carriageway and tunnel, replacing the existing single carriage road. 

Once complete, the A303 Amesbury to Berwick Down Improvements Scheme will enhance the Stonehenge World Heritage site and the natural setting of the stones, while bringing environmental benefits by reducing congestion and increasing biodiversity around the site. 

Costain will play a significant role in ensuring the successful delivery of the works and its benefits. 

It will work closely with Mott MacDonald, supply chain partners, road users and the local community to implement efficient, practical solutions to the complex challenges the project presents. 

Sue Kershaw, managing director for transportation at Costain, said: “This award comes as a result of our strategy to bring together the whole range Costain’s capabilities to deliver for our customers and transform the performance of the UK’s infrastructure ecosystem. 

“It demonstrates the calibre of Costain’s growing consultancy expertise and the value of our differentiated proposition in the market. Together with our customers we will create connected, sustainable infrastructure that helps people and the planet to thrive. 

“This is the second award for our long-standing strategic partnership with Mott MacDonald and evidences the delivery of our strategy in meeting the wider needs of our customers.”   

Ken Norbury, transportation managing director at Mott MacDonald, added: “We have assembled a world class multidisciplinary team to support the delivery of this vital upgrade project. We are proud to be chosen alongside Costain and look forward to working collaboratively with the project team. 

“This is an outstanding project that will improve peoples’ lives, enhance the World Heritage Site and its surrounding environment, which the country will be proud of.” 

National Highways is committed to delivering a dual carriageway route along the A303/A358 corridor between the South-west and the South-east. Removing the traffic bottleneck past Stonehenge will improve connectivity and help open the South-west, unlocking economic and social benefits for the region. 

This forms part of the Government’s national Road Investment Strategy. 

The scheme includes a tunnel, around two miles long, to remove A303 traffic from a large part of the Stonehenge landscape. 

In doing so, the tranquillity and natural setting of the Stones will be restored to benefit visitors’ experiences long into the future.

The scheme will also improve the quality of life for local communities by providing a bypass for Winterbourne Stoke and relieving nearby towns and villages of traffic. 

Derek Parody, National Highways’ project director for the A303 Stonehenge scheme, said: “We’re pleased we have completed the procurement process, and once the redetermination process is finalised, and should the Development Consent Order be granted, having this expertise in place will put us in the strongest possible position to deliver this transformational scheme and deliver the benefits we know it can.  

“Our Delivery Assurance Partner will help us to successfully coordinate and oversee the development of the scheme moving forward. This collaborative team will continue to work with local stakeholders, heritage bodies and local communities to deliver a successful and exceptional project for the area.” 

The Costain and Mott MacDonald team will deliver a range of services including project management and integrated project controls, contract management, construction monitoring and assurance, tunnel commissioning and testing assurance.

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