The future development of the railway system in Great Britain is considered a central feature of the Ten Year Plan for transport and the decisions as to the scale and distribution of funding required and its impact on travel and transport provision are being determined in the first instance through the use of the National Transport Model (NTM). The NTM has been undergoing a wide ranging programme of development in order to make it more spatially orientated and capable of assessing transport impacts on a corridor basis rather than on a regional, conurbation or national level. One element of the development programme has been the specification and implementation of a detailed rail demand and network based modelling framework that integrates with the core NTM components, facilitating an integrated approach to both individual and policy choices across different modes of travel. The objective of the exercise was to provide a modelling framework that would enable the impacts of wide ranging national policy assumptions on issues such as road infrastructure provision, charging options, and rail investment to be assessed for the main inter-urban rail corridors and rail commuter services. The rail modelling framework integrates the growth projections derived from the limited area types and distance bands used in NTM to a detailed rail demand model. The detailed model has a network basis and comprises over 1300 zones, and represents all stations on the national rail and London Underground systems. The development of the model has raised many issues with respect to the integration of coarse and detailed model frameworks and the paper presents an overview of the key issues and the insight that these provide for the development of spatially hierarchical structured modelling frameworks. The paper also describes the development of the detailed rail network and demand models, the integration of growth projections from the NTM; the cost interface between the detailed rail model and NTM, the validation of the detailed rail network model; and the output modules for user benefits, overcrowding assessments and environmental emissions. For the covering abstract see ITRD E124693.
Abstract