VolkerFitzpatrick Kier JV: The Luton DART Tunnel

The Luton Direct Air-Rail Transit (DART) Project is a 2.1km long cable-driven light metro system to connect London Luton Airport with Luton Airport Parkway railway station. One of the most complex sections of the project was the construction of a 350m cut and cover tunnel passing under the Airport’s Taxiway Bravo and Approach Road, whilst not affecting over 70 airport-critical control and communication services. To enable the taxiway and road to remain live throughout the works, the tunnel was constructed in four isolated sheetpiled cofferdams through clay overlying chalk above the water table. Cofferdam One and Two were constructed first with a 90m gap between each of the headwalls to allow aircraft to continue to use the existing Taxiway. Once constructed the tunnels were backfilled and a diverted Taxiway and Road installed over Cofferdam One and Two respectively, allowing works on Cofferdam Three and Four to commence. Cofferdam Three posed a challenge of being completely airside requiring the works to be meticulously planned alongside airport operations and for all operatives, equipment and materials to go through rigorous airside security checks. The project team consisted of 3 Apprentice, 3 Graduate and 1 Section Engineers, led by a Site Agent.

This award seeks to recognise excellence in delivery of a tunnelling project or tunnelling-related element of a project up to the value of $500M that was completed between July 2019 and July 2020 Judges will be looking to reward the project that best meets or exceeds the design brief and/or client expectation but that also have sought to advance industry best practice and have worked in a truly collaborative way.