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Technologies That Enable Congestion Pricing - Table of Contents

Technologies That Enable Congestion Pricing—A Primer

Congestion-Pricing Options

Photo. Overhead view of a large city block, depicting tall buildings and the city traffic on a large street.

In the United States and around the world, several strategies exist on how to implement congestion pricing. These strategies consider how best to influence traffic patterns, match the local geography, fit political boundaries, and match the policy framework of the implementing jurisdiction.

The four major types of pricing include:

  • Priced Lanes: Fees for low-occupancy vehicles to utilize excess capacity on new or existing high-occupancy vehicle (HOV) lanes (e.g., I-15 FasTrak® between Kearny Mesa and Rancho Penasquitos, California1, or the SR-91 Express Lanes in Orange County). Pricing can be fixed per road segment, vary by occupancy (e.g., HOV2, HOV3, or HOV4+), vary by occupancy and time of day, or vary dynamically based on the degree of congestion in the adjacent “free” lanes.
  • Variable Tolls on Entire Roadways: Fees placed on existing and new roads, bridges, and tunnels to pay for access onto the road or facility and to pay for the cost of maintenance and construction of the road, whether the government or the private sector builds the toll facility. The toll is variable, that is, prices rise and fall depending on the measured traffic level or estimated traffic level based on time of day.
  • Zone-Based Charges: Fees levied to charge for access or use of a designated road network in and around heavily congested areas or urban centers. There are several forms of congestion pricing, including cordon charges, area charges, and zonal charges. These variations are explained as follows:
    • Cordon charge—A flat or variable fee levied for crossing the designated boundary around an urban center. Cordons can be used for entrance or exit of any road designated by the cordon(s). Manchester, England, has proposed a cordon charge to enter the regional center only during the morning peak period inbound and the evening peak period outbound. It uses the natural boundary of the M-60 motorway, which circles the regional center and city of Manchester, and includes a proposed second cordon boundary closer to the city center. Stockholm is an example of a single cordon charge.
    • Area charge—Charge for all trips whether they originate outside the boundary and cross the designated boundary or originate inside the boundary and never cross the boundary during the charging period. The London Congestion Charging System levies a flat fee on any vehicle on public roads inside the designated charging zone or crossing into or out of the boundary. It also charges the same daily fee for all vehicles regardless of size or time spent in the charging zone.
    • Zonal charge—Mini-cordons within or around an urban center where fees are charged for entering each mini-cordon that can be contiguous or spatially separated with free roads in between them. Charging for each mini-cordon can be the same across all cordons or vary between them and can also vary by direction or time of day for peak-period charging or variable charging based on the degree of congestion. Mini-zones are typically drawn around known geographical or political boundaries that are easily and clearly understood by the local residents. Florence, Italy, has several mini-cordons based on centuries-old political boundaries. Residents of any specific mini-cordon are not charged for travel within their “home cordon” but are charged for entry into a neighboring mini-zone or cordon.
  • Area-Wide or System-Wide Charges: Fees levied on a vehicle based on factors such as vehicle type, distance traveled, time of day, type of road, vehicle emissions, or type of power train (e.g., diesel engine, gasoline engine, bio-fuel engine, hybrid, electric, or hydrogen). This type of charging includes:
    • Truck or heavy commercial vehicle pricing—Fees levied only on trucks or heavy commercial vehicles that typically reflect charges for the weight carried (load) and distance carried on the road network. Current truck pricing examples include New Zealand’s Road User Charging, Switzerland’s truck tolling, and Austria’s and Germany’s MAUT systems.
    • Strategic-road-network charge—Levies imposed as spot charges on major roads or congested network links in or into city centers. Strategic-road-network charges can be a continuous series of charging points along a major access road into the urban center. These charges can vary by location and time of day, in addition to type or classification of vehicle. Strategic-road-network charges were considered in the Auckland, New Zealand, Road Pricing Evaluation Study(2) and are part of the Singapore Electronic Road Pricing (ERP) system.(3) In Singapore, these charges apply not only on the strategic road network approaching the central business district (CBD), but also to specific congested areas or streets inside the boundary of the cordon charge.(3)

These options define the major types of pricing that exist today, but the list is not all inclusive, and new concepts or combinations of the above may develop in the future. For example, Milan, Italy, has introduced an environmental charging system, and Hong Kong has explored a concept of eco-point charging or personal carbon-based trading in which users gain or lose “eco-points” based on their travel choices, time, and distance traveled.(4)