Predictions have been made of the distortions and changes in clearance in the Bakerloo Line tunnels where they pass beneath the excavation for the Waterloo International Terminal (WIT). To make the predictions a comprehensive site investigation was carried out at the site and aimed, inter alia, at determining the in situ stress state and non-linear small strain stiffness of the soils. The sequence of soils at each location is described. It consists of alluvial clay and Thames gravel. The former contain sand/silt seams. The effect on the in situ stress state of the construction history at Waterloo, including driving of the tunnels, and of groundwater flow towards the tunnels was taken into account in the modelling. Modelling was carried out using a series of plane strain finite element analyses. It was carried out using the ICFEP program. The construction sequence modelled is described in some detail. Brief details of the in situ measurements made to monitor the distortions on the Bakerloo Line tunnels are also provided. The predicted distortions and the measurements made during construction are compared. For the covering abstract see IRRD 859983.