Distance-based Road User Charging: from Theory to Practice
WINNER OF The Neil Mansfield Award
A Balwani, B Arch, Halcrow Group Limited, UK
This paper investigates the issues involved with the design of universal distance-based charging for implementation of National Road User Charging schemes and evaluates its impacts on route-choice, travel characteristics and demand for road space.
Pricing for road use has emerged as a tool to manage travel demand. The current implementations of road user charging are largely limited to cordon and area-based charging with limited examples of distance-based charging. However, there is wealth of theory available on the subject and the concept is fast gaining momentum in light of the recent promises towards National Road User Charging by the Netherlands and UK. While there are examples of distance-based charging for road freight charges in Germany and partial national schemes exist in Austria and Switzerland in the form of lorry road user charging schemes, distance based charging is now being seen as the only mechanism that can match the sophistication of national road-pricing schemes in addressing congestion.
This paper investigates the theoretical aspects of distance-based charging that distinguish it from other charging practices and conducts research into the design and impact of the implementation of a universal distance based charging system using a real life network. The city of Leeds in the UK has been taken as a case study on the grounds that it is a large urban conurbation, which represents a typical urban city with appropriate network hierarchy, size and structure for assessing the effects of charging. Several distance based charging regimes comprising of different charge rates varying by road type, location and time of the day have been designed based on travel and congestion characteristics of the given city. The work incorporates procedures within a detailed network supply model to represent how a range of different permutations of distance based charges across a given network (charging regimes) affect route-choice, travel characteristics and demand for road space. A social cost benefit analysis of the various charging regimes under ?revenue neutral? and ?revenue additional? cases has been undertaken to conclude on the economic benefits of various regimes.
Evidence suggests that distance-based charging can reduce number and length of trips, reduce congestion, accidents and pollution, and provide net economic benefits and revenues but it may not be as non-disruptive and equitable as advocated. Distance based charging can lead to traffic-disruption in the absence of a cautious decision on the ?charge levels? for various roads; the hierarchy of these charge levels across the network; and, the difference between the charge levels. Analysis suggests that a successful charging scheme requires a strategic hierarchy of charges with lower charges on principal roads than minor roads at a given time. With re-routeing as the dominant response, large variations in charges across the network yield unexpected results and simpler regimes with less variation perform better with lesser transfer of traffic from high-charged to low-charged routes. It is also found that the sensitivity to small charge differences is less for low charge-levels, compared to high charge-levels, hence, low charging regimes produce better results with lesser traffic rerouting. The social cost benefit analysis further reinstates that low-charges with less variation across the network give good results if revenue generation is a minor objective, offering a more acceptable version of distance based charging.
Overall, the results indicate that although universal distance-based charging has a lot to offer, a careful design of the scheme based on the network-conditions and sensitivity to charge-levels is critical to achieve the maximum benefits.
Association for European Transport