Developing a method to search for the causes of uncertainty in a nascent transport planning project

Abstract

The transport planning decision process is, in theory, underpinned by rational analysis of travel behaviour and application of transport economics but project outcomes do not always follow the results of that analysis. Uncertainty is evident at all stages of the project development; as the concept emerges and as it moves through the subsequent assessment and decision processes. This research has investigated and demonstrated a method that identifies uncertainty focussing on the early stages of the project lifecycle and also provides an understanding of the factors that drive it. The method used a backcast scenario to elicit the causal relationships between elements of the planning and decision process in structured interviews with stakeholders. Qualitative analysis techniques were used to identify the active elements of the process, the causality between the elements was explored using the Cross Impact Matrix Model to evaluate their influences and dependencies and identify those driving uncertainty in the planning process. In this research, the Cross Impact Matrix Model was extended to analyse stakeholder opinions both individually and collectively, and investigation was undertaken into the parameter sensitivity of the analysis method. The case study was based on a disused railway where several studies into re-opening it have resulted in contradictory views on its mode of use and on the achievable benefits. In the scenario used in the case study, the rail service is re-instated for light rail use in conjunction with a new sustainable urban area anchored on an existing small village. The findings in this case study were that presence of strong leadership and collaboration between Local Authorities were the most influential determinants for progress and the prime causes of uncertainty were the economic environment, planning policies, and perceptions of passenger utility. Although these results emerged from a specific scenario, the methodology was demonstrated to be a powerful generic tool to identify the elements that create criticalities in planning for any scheme.