| dc.description.abstract | The goal of this research was to develop a mileage-based user fee (MBUF) system that incorporated air quality goals through the use of performance measurement. A framework of performance measures was developed that addresses multiple aspects of transportation which affect air quality. In this research, performance measures were selected that relate travel to the emission of air pollutants. Better performance would contribute to achievement of objectives, which would in turn contribute to achievement of air quality and energy goals.
Performance measures included aspects of driver behavior and characteristics of the vehicle being driven. Average vehicle characteristics were used to determine base emission rates for five pollutant types, which were scaled to reflect characteristics on an individual’s vehicle. Driving behaviors were translated to changes in emissions based on emissions software modeling. Based on these results, base emission rates were adjusted to reflect an individual’s performance in terms of driving behaviors and vehicle type. A performance score was then determined for each pollutant type by comparing the scaled emission rates to anticipated rates across the population. These performance scores were then aggregated into a final score. To determine the actual mileage fee assessed to an individual, the resulting final performance score and system-level average score were used. An example of the performance measurement framework and pricing system was provided through a small case study. Use of transportation elasticity values was demonstrated to relate desired mileage changes to required changes in pricing. A decrease in mileage would have a direct decrease in the amount of pollutants emitted.
Air quality concerns are one policy goal that has the potential to be included as an important part in any road-pricing system. While such goals are not currently given priority in mileage-based pricing pilot studies, the framework developed in this research illustrates how air quality could be included in pricing attempts in the future. With any mileage-based fee system, extensive public outreach and education would be vital to implementation, and use of a pilot program would be recommended. Mileage driven would likely decrease in response to pricing, and over time the vehicle fleet will improve as well. Consideration must be given to equity concerns, as lower-income drivers may have more difficulty changing driving patterns or purchasing better vehicles. Finally, policy-makers would have to determine the extent of data desired. Increased data would help to address air quality goals, but the benefit of improved data would have to be weighed against the cost of obtaining it. | en |
