Channel Tunnel Rail Link 250: Partnering at its best

Nuttall – Wayss and Freytag – Kier Joint Venture were proud to be part of the team which delivered the Channel Tunnel Rail Link (CTRL) on time and on budget.

CTRL Contract 250

Our role as main contractor on CTRL Contract 250 entailed the construction of twin 7.15m diameter running tunnels 5.3km long from Dagenham to Barking. The £150m three-year project also involved the construction of ventilation shaft, ventilation tunnels, cross passages, a cut and cover tunnel, retained cut and the manufacture of the precast concrete tunnel linings.

The running tunnels passed beneath live Network Rail and London Underground infrastructure and densely-populated urban areas across east London. A significant portion of the contract involved the design and installation of extensive monitoring, instrumentation and mitigation works along the route. This included real-time monitoring and automated jacking of bridge decks to compensate for ground movements induced by the tunnelling machines.

Collaborative working methods and value engineering were at the heart of the team’s effort on CTRL 250, and the team delivered £5.5 million of savings through two key value engineering initiatives.

These initiatives also brought about other benefits including reduced programme, improved buildability, an overall reduction in risk and the de-linking of critical programme activities.

As a result of the initial partnering arrangements, an early agreement was made to form a formal “Alliance” between the client’s project manager and the four contractors engaged to construct the London Tunnels section. This unique “Alliance” then managed all four projects and the client’s obligations under a single organisation and budget and with shared objectives. The Alliance formed a single project team for procurement, management of interfaces, cost controls and risk management, and joint responsibility and initiatives on Health and Safety, Quality and Environment across the whole of the London tunnels section.

On budget and on time

It is testament to the success of the unique Alliancing arrangement that, despite concerns that the London Tunnels were the highest risk in the northern section of CTRL, these works were handed over on time, on budget and with no outstanding issues.