Joint venture contractor Sir Robert McAlpine-Wayss & Freytag-Bachy had a very tight programme to construct the huge station box which measures 405m long by 32m wide by 25m deep.
By any standards it was a big dig. But working in the contaminated former gas works site on Greenwich Peninsula and excavating through two aquifers at different levels required both dewatering and a high level cofferdam before the anchored secant piled sides could be installed.
The giant cathedral-like station was engineered by Robert Benaim-Works joint venture with architect Alsop & Stormer. It was originally intended as the focus for redeveloping a rundown area of south east London. This remains key to the plan but has been superseded by the station's role as the main terminus for the Millennium Dome.
Over 100,000 visitors are expected at the Dome each day next year, with the majority arriving by Tube via North Greenwich. However, once the Millennium celebrations are complete the new station is expected to handle around 7,000 passengers in the weekday peak rush hour from surrounding office and residential developments which will be constructed on the former gas works site.
In addition, a new bus terminus above the station and extensive long term car parking will allow commuters from outside the capital to use the station as a point of entry in to the Tube network.
Excavation had to be completed in time to launch the two Lovat earth pressure balance tunnelling machines on their journey to the Canning Town portal. Extra internal walls were built at each end to section off the critical areas and ensure the deadline was not missed.
But while the excavation went ahead of schedule, construction was slowed after the project team had to reappraise the design and increase the steel content of the box to improve longterm robustness.
The result is an huge underground space, which with its raked, elliptical, blue-tile-clad columns and hanging concourse, will delight passengers throughout the next century.