Economic, Environmental and Social Impacts of Changes in Maintenance Spend on the Scottish Trunk Road Network

11 Impacts on customer satisfaction

11.1 Overview

Transport Scotland carried out road user satisfaction surveys in 2007, 2009 and 2010. However, many questions changed between 2007 and 2009 so the two surveys which are most comparable are the most recent 2009 and 2010 surveys. As part of this study the feedback received from these surveys was reviewed and interpretations have been made based on an understanding of road user surveys identified in the literature survey.

11.2 Literature review

A recent study (Ramdas, Thomas, Lehman, & Young, 2007) showed that user requirements and levels of acceptability of the surface condition of paved surfaces are influenced by more than just the condition of the surface. Other effects include media reports, experience in other parts of the country, or other countries, and non-condition related factors (e.g. congestion, traffic management measures such as speed humps).

That study concluded that the two main condition factors that influenced user opinions and satisfaction were 'safety' and 'ride comfort'. Sudden unexpected bumps were classed as unacceptable. It was observed that users expect to not notice the road surface they travel on. In general, any condition aspect that caused them to react to the surface condition and took their attention away from driving was construed as unsafe and unacceptable. User requirements were mainly centred on the need for safe surfaces (i.e. level with good grip) with no unexpected or sudden changes in ride quality. Comparison between user perceptions and engineering data showed that the condition parameters related to ride quality (i.e. 3m LPV, 10m LPV and the bump measure from SCANNER surveys) aligned well with user perceptions of poor ride quality. The other condition aspect that affected ride quality was poor or failed patches. The RCI was high on most roads which users perceived to be in unacceptable condition.

Road user participants in that study showed a good level of understanding of issues related to highway management, including the types of defects commonly encountered, maintenance treatments used and also the budgetary constraints under which highway authorities often operate. It was found that expectations could be managed if users understand the constraints associated with the current maintenance budget and Road Administration objectives. Road closures for maintenance were acceptable if they meant the road surfaces would be repaired to a high standard with good quality materials and would last for many years.

A similar study (Benbow, Nesnas, & Wright, 2006) found that the LPV wavelengths that cause users most discomfort are those in the range of 1-5m. Wavelengths of 5-10m had a much smaller effect and higher wavelengths had no effect. IRI values did not correlate with the user perception as well as 3m LPV.

In summary, if user expectations are managed with additional knowledge of why decisions have been made and how these decisions will not put road user safety at risk, user satisfaction can be kept at an acceptable level.

11.3 Customer satisfaction surveys and potential impacts

From the subjective assessment described in Section 6, the main effect of the lower maintenance budgets that users will see will be reduced roadworks, deteriorating network conditions in the longer term, and possible reductions in operations such as less maintenance to keep street lights operational. The subjective assessment made limited cuts to operations which maintain route reliability, accessibility and safety.

From the results of the 2010 survey by Transport Scotland, it is clear that the area of most concern for road users on the Scottish trunk road network is the general condition of the road surface. The key observation in the report is that with the significant reductions in the pavement budgets, this concern is likely to increase.