Modeling of Effects of Peak Load Pricing on Metropolitan Network and Activities

Peak load pricing has long been seen as a way to internalize externalities, as a set of incentives to shift peak hour trips to off-peak periods, and as a mechanism to generate revenues. However, how travelers trade time for money and respond to peak–off-peak pricing differentials is an open question that generates some timely and related questions, including the following: (a) How can the activity location and traffic implications for multiple times of the day in a major metropolitan area be modeled? (b) What are the network effects of peak load pricing on selected routes on level of service and urban development? It is possible to conduct simulations on actual highway networks to treat these questions. None of the urban models, however, can examine simultaneous route choice and time-of-day choice involving millions of travelers, thousands of traffic network zones, and hundreds of thousands of network links in an equilibrium system. This research addressed these questions by extending the Southern California Planning Model so that it could be used to determine the effects of pricing schemes on the time-of-day choice for travel, trip distribution, and network traffic for the greater Los Angeles, California (five-county), metropolitan area. The model estimated improvements in levels of service throughout the highway network for alternative toll charges. The model examined how drivers traded route choice with time-of-day choice against the option of traveling less. The approach also estimated the revenues implied for local jurisdictions as well as the possible effects of altered development pressures on land use throughout the region. The effects of two different toll scenarios were compared, and policy implications were offered.