Planning for People and Pedals: Integration of Walking and Cycling in Transport Modelling and Analysis
Martin Wedderburn, Independent Consultant
Active modes are under-represented in transport data capture, analysis and modelling. While there has been progress in single mode analysis techniques, a number of challenges remain for their full integration into multi-modal modelling tools.
There is general agreement on the benefits that can be derived from an increase in either walking or cycling activity. While the term ‘walking and cycling’ is frequently used by transport professionals, a number of commentators have pointed out that walking and cycling are different in many ways and that very different approaches are required to increase walking and cycling levels.
One factor common to both modes is their traditional under-representation in tools for transport data capture, analysis and modelling. This paper presents some examples of progress in the development of single mode forecasting techniques. Pedestrian movement has been modelled through the use of calibrated mode-specific impedance parameters to distribute and assign walking trips in detailed area models. A number of studies have sought to quantify the role of different factors including infrastructure, trip purpose, user demographics and lifestyle, and end-of-trip facilities on the propensity to cycle.
However, if the impact of serious investment in walking and cycling measures is to be assessed using the current suite of mainstream multi-modal modelling tools, a number of significant challenges remain. The absence of reliable methods to quantify the complex range of determinants driving changes in walking and cycling behaviour has implications for the choice hierarchy underpinning strategic transport modelling as a whole. This paper summarises the definitional and sampling issues that affect our interpretation of walking and cycling data, including the treatment of walking and cycling as public transport access and egress modes. Finally, whereas progress has been made in developing pedestrian-specific assignment models, the interaction between cyclists and vehicles presents challenges in predicting cycle route choice, and the assessment of highway capacity impacts has been assessed in highway assignment and micro-simulation models.
While progress has been made in many areas, the author will highlight several key gaps and priorities for further research. It is important to acknowledge the different challenges and research priorities facing walking and cycling.
Association for European Transport