The key themes and case studies on this site refer to many of the tools that are available to support strategic decision making on land use/transport issues. This page provides references and links to these tools and others relevant to the topic.
Scenario building methodologies are used to help imagine and examine the future more effectively (Kahn and Wiener, 1967; Schwartz, 1996; Van der Heijden, 1996). The typical scenario process highlights the current drivers of change and uncertainties and explores how they might develop in the future. The result is a set of images that offer alternative views of what the future might look like. Originally developed in the corporate world to examine business futures, they are increasingly being used in governmental studies to examine possible societal futures, including in land use and transport planning. The Foresight Intelligent Infrastructure Systems project and the current Land Use Futures project provide examples.
A subset of scenario methods is backcasting – where desirable futures are imagined and a programme of implementation ‘cast back’ from a future date. The OECD study (2000) on ‘Environmental Sustainable Transport’ and the ‘Visioning and Backcasting for Transport’ series of studies (Hickman and Banister, 2004-ongoing) provide examples of some of the methodologies available.
Transport models forecast future travel demand based on past behaviour. They usually assume a continuation of past trends subject to a modified transport network (and sometimes a new land use structure). Models are, of course, abstractions of reality but are used by transport planners as a means of clarifying assumptions about travel behaviour and comparing potential future outcomes.
Models take a variety of forms, largely depending on the nature of the study area, the problems to be addressed and the potential solutions to be considered. WebTAG provides a summary of different modelling approaches and tools.
Modelling software commonly used to develop macro-level models in the UK include SATURN and CONTRAM for highway modelling and EMME/2 for public transport modelling. Software such as TRIPS is used to predict public transport mode choice within a multi-modal model based on SATURN or similar software. A number of examples are given below.
- The National Transport Model (NTM) provides a means of comparing the national consequences of alternative national transport policies or widely-applied local transport policies, against a range of background scenarios which take into account the major factors affecting future patterns of travel. TEMPRO allows access to the national Trip End Model projections of growth in traffic demand, and the underlying car ownership and planning data projections.
- Accession – software for developing a model of accessibility. Can be used in Local Transport Plans and to assess the accessibility of individual sites or areas. Travel time maps are used to indicate accessibility to/from a given location using contours (or isochrones) of equal travel time. Various approaches can be used to calculate travel time maps as described in the DfT’s Guidance on Accessibility Planning in Local Transport Plans.
- SATURN – Simulation and Assignment of Traffic to Urban Road Network. Highway modelling software used to model a range of different types of traffic network from individual junctions to major infrastructure.
- CONTRAM – software to model traffic demand and congestion.
- EMME/2 –software designed for modelling multi-modal networks with all modes integrated, particularly used in public transport modelling.
- Railplan – a model based on EMME/2 software to model the public transport network (particularly in London and the South East).
- PTAL – Public Transport Accessibility Levels. Used in London to measure the accessibility of a particular location in relation to the public transport network.
- VISSIM – A simulation and modelling software package for modelling complex interchanges and interactions between different transport modes.
- PEDROUTE/LEGION – software that models pedestrian movements in confined spaces such as stations.
- Space Syntax – a set of theories and techniques for the analysis of spatial configuration, often applied to the design of streets and buildings and in correlating layout with social effects such as crime and traffic flow.
- ARCADY – Assessment of Roundabout Capacity and Delay.
- PICADY – Priority Intersection Capacity and Delay.
- TRANSYT – Traffic Network Study Tool. Software allowing a network of linked signalised junctions to be modelled to determine optimum signal timings and junction capacities.
- OSCADY – Optimised Signal Capacity and Delay.
- LINSIG – software allowing the modelling of signalised junctions.
- TRICS – A UK-wide database containing trip generation data for a range of developments.
- TRAVL –software allowing access to a range of travel surveys carried out for developments (across London).
In the UK, the MEPLAN and LILT models, among others, have been used to forecast the travel behaviour outcomes of the interaction between land use and transport over time (known as land use and transport interaction models, LUTI). LILT is one of the earliest LUTI models that was applied first in Leeds. It can be conceptualised as a looped iteration of the four stage model over time. The MEPLAN modelling package integrates land use and transport elements within an economic framework, and has been used in the UK for regional forecasts. In 1999, the DfT commissioned a review of LUTI models that is available here.
The Highways Agency has commissioned the Penelope (Program Evaluating North of England Land Use Options and Population Effects) tool. Penelope is a GIS-based tool that is an add-on to a generic regional transport model. It estimates the distribution of traffic associated with new developments (based on the original model forecasts) and the results can be fed into a Traffic Analysis Tool that is used to assess the impact of all developments on the Strategic Road Network within each Local Authority.
Transport appraisal is a core part of the transport planning process, allowing the comparison of different investment options or strategies. Again WebTAG provides guidance on appropriate methodologies.
Transport Assessments (TAs) are carried out to examine the potential impacts of a new development, particularly where they are likely to include significant transport implications. A TA is usually prepared and submitted with a planning application for the development. It is used to determine whether the impact of the development on transport is acceptable. TAs are normally produced by developers and are used by decision makers in the planning process.
Travel Plans are produced to encourage staff to use alternatives to single-occupancy car-use. A Travel Plan, for example, could include car sharing schemes, cycling facilities, a bus service or restricted car parking allocations and flexible-working practices such as home working, remote access and video conferencing. Travel plans can be developed for employment sites, schools and areas of new housing; they are often conceived as part of wider ‘smarter choice’ behavioural change initiatives.
The purpose of Sustainability Appraisal (SA), mandatory under the Planning and Compulsory Purchase Act 2004, is to promote sustainable development through the integration of social, environmental and economic considerations into the preparation development plans.
Regional Planning Bodies and Local Planning Authorities must also conduct an environmental assessment as part of their development plan process, in accordance with the requirements of European Directive 2001/42/EC "on the assessment of the effects of certain plans and programmes on the environment" (the Strategic Environmental Assessment or 'SEA Directive'). Whilst the requirement to carry out a Sustainability Appraisal and a Strategic Environmental Assessment are distinct, it is possible to satisfy both through a single appraisal process.
Wider Related Resources and Useful Links
Commission for Integrated Transport Research Studies: a number of CfIT-sponsored reports have been produced from 1999-ongoing. Those most closely related to this project include:
Provided below are links to the CfIT research studies of relevance to this topic:
- Climate Change and Transport: Meeting the Challenge of Ambitious Carbon Reduction Targets, 2009
- Transport and Climate Change, 2007
- Response to the Government’s Planning White Paper, 2007
- Integrated Transport Delivery – Is It Working Across Government Departments?, 2006
- Sustainable Transport Choices and the Retail Sector, 2006
Related Planning and Transport Research and Good Practice Guides: a wide range of research outputs and guides have been produced covering issues related to this project, including by the Department for Communities and Local Government, Department for Transport and the Commission for Architecture and the Built Environment.
The Royal Town Planning Institute, Institution of Highways and Transportation and Transport Planning Society also disseminate best practice and provide professional development for land use and transport planners.