EC Harris has won a contract from Hitachi Rail Europe to manage the delivery of three intercity express depots, which will be built on the Great Western Main Line between Swansea and London Paddington in the UK.
The depots will be constructed over the next three years at London North Pole, Bristol Stoke Gifford and Swansea Maliphant, and will support the next generation of intercity trains.
This timescale will allow Hitachi to introduce a new fleet of high-speed trains, which will help to reduce journey times, increase reliability and improve the overall passenger experience.
Hitachi Rail senior vice president Andy Barr said: "The delivery of the three new depots will be vital to the overall success of the intercity express programme."
EC Harris will be responsible for the completion of the overall programme, offering project, commercial and risk management services.
EC Harris partner Simon Jones said: "These new depots will be crucial in helping to facilitate the introduction of new trains on to the network and we look forward to working with Hitachi and the chosen contractor to deliver a successful outcome."
The UK government is carrying out a £4.5bn programme that will add around 100 electric trains and bi-mode (diesel and electric) intercity trains along the Great Western line.
The stations that will be covered in the programme include Oxford, Swindon, Reading, Cardiff, Swansea, Bath and Bristol, as well as East Coast Main Line stations, such as Peterborough, York, Doncaster, Newcastle, Edinburgh, Aberdeen and Inverness.
Hitachi will build the trains at a new factory in County Durham, north-east England, which will be in operation by 2013.