Thomas Light

Making Congestion Pricing Equitable

Transportation policy makers increasingly consider congestion pricing a promising option for addressing urban traffic congestion problems. Although some congestion pricing projects have been undertaken in the United States, many proposals have been rejected because of concerns that congestion pricing is inequitable. This paper identifies and assesses ways of making congestion pricing equitable. The authors review notions of equity applicable to congestion pricing and explore the equity issues that arise in the context of cordon and area pricing systems and high-occupancy toll lanes.

Understanding the Potential of Variable Tolling to Smooth Congestion on Downstream Facilities: Applications of a Joint Time-of-Day and Route Choice Model

The aim of this research was to understand the conditions under which time-varying tolls could be used to effectively smooth congestion on a downstream, untolled roadway. This question was answered in the context of the 183A Turnpike in Texas, but the analysis was extended to draw lessons for the potential use and evaluation of time-varying tolls as a congestion management strategy elsewhere. The study relied on two primary data sources: license plate reader data, to observe traffic routing, and a stated preference survey, to understand travelers’ trade-offs between travel time, tolls, and time-of-day shifts. A joint time-of-day and route choice model was developed and implemented in a spreadsheet for the rapid evaluation of a range of scenarios. Model inputs were then varied across key dimensions to achieve a better understanding of the conditions under which such a strategy might or might not be effective. The analysis revealed that under the conditions and constraints specific to the 183A corridor, time-of-day tolling would have a limited effect, but that there are a range of conditions for which time-of-day tolling could be a cost-effective means of managing downstream congestion.

Comparison of Wind-Tunnel Pricing Models for Government Facilities

NASA’s national-class wind tunnels are almost equally dependent on fee revenues as on government funding. Changes in wind tunnel fees can significantly impact annual revenues. This paper explores six approaches for pricing the use of NASA wind-tunnel test facilities: (1) marginal cost pricing; (2) two-part pricing with full cost recovery; (3) two-part pricing with subsidization; (4) average cost pricing; (5) average cost pricing with subsidization; and (6) a policy where testing facilities can be used at no charge. The analysis compares these pricing strategies in terms of their efficiency, effect on NASA’s budget, and fairness, using a simple economic framework. Not charging for use performed poorly on all criteria; the other five approaches performed well on at least one criterion.