Interstate 2.0: Modernizing the Interstate Highway System Via Toll Finance

The 20th-century fuel tax cannot deliver a second-generation Interstate highway system, 21st-century all-electronic tolling can

The Interstate highway system is America’s most important surface transportation system. With just 2.5% of the nation’s lane-miles of highway, it handles some 25% of all vehicle miles of travel. It served to open the country to trade and travel, enabling the just-in-time logistics system at the heart of U.S. goods movement. Yet the first-generation Interstate system is wearing out. Most of the pavement has exceeded or is nearing its 50-year design life, meaning that nearly the entire system will need reconstruction over the next two decades. In addition, more than a hundred interchanges are major bottlenecks, needing redesign and reconstruction, and about 200 corridors need additional lanes to cope with current and projected traffic.

The need for massive investment to transform the first-generation Interstate into what this report calls Interstate 2.0 occurs just as our 20th-century highway funding system—based on fuel taxes and state and federal highway trust funds—is running out of gas. Steady increases in vehicle fuel economy, the lack of inflation indexing of fuel tax rates, and political gridlock over increasing fuel tax rates all make it very difficult even to maintain current pavement and bridge conditions and prevent congestion from getting even worse. The transportation community agrees that we need to phase out fuel taxes and replace them with a more sustainable funding source, generally agreed to be mileage-based user fees of some sort. But no consensus exists on how and when to do this.

This study seeks to address both problems: replacing the aging Interstate system with a 21st-century Interstate 2.0 and taking the first major step toward implementing mileage-based user fees. It proposes that the United States finance the Interstate 2.0 project based on per-mile tolls collected using all-electronic tolling (AET). Over several decades, the transformation of the Interstate system, state by state, would convert at least one-fourth of all travel from per-gallon fuel taxes to per-mile charging.

The study makes quantitative estimates for each state of the cost of reconstructing the existing Interstates, identifies specific corridors in each state that need widening, and estimates the cost of doing so. Reconstruction is estimated at $589 billion in 2010 dollars and lane additions at $394 billion, for a total 2010 cost of $983 billion. To get a handle on the feasibility of toll financing, the study models a tolling system based on 3.5¢/ mile for cars and 14¢/mile for trucks, indexed annually for inflation. Using state-by-state estimates of annual growth in travel by cars and by trucks, over a 35-year period, it calculates the net present value (NPV) of toll revenue and compares that with the net present value of construction and reconstruction costs. Overall, the NPV of revenue equals 99% of the NPV of cost, indicating that the overall system is likely to be toll- financeable.

Since the calculations were done state by state, using the latest cost data from the Federal Highway Administration and state-specific forecasts of vehicle miles of travel based on a recent FHWA forecasting model, the study provides toll-feasibility estimates for each of the states. While not all states could fully toll-finance their Interstate modernization based on the low toll rates used for the national analysis, all but five or six rural states could do this with somewhat higher toll rates than the baseline ones used in this study—rates comparable to those on recently financed toll roads.

The cost estimates include fitting the entire Interstate highway system, both rural and urban, with state-of-the-art all-electronic tolling (AET) equipment. Fully interoperable tolling already exists statewide in California, Florida and Texas, as well as the 15 E-ZPass states in the Northeast and Midwest. With AET there would be no toll booths or toll plazas, and by 2016 nationwide electronic tolling interoperability is expected to be in place. That will mean a motorist needs only one account and one transponder to travel throughout the United States.

To make the transition attractive to highway users, the study proposes it be implemented on the principle of “value-added tolling.” That means tolls would only be introduced in a corridor once it was reconstructed and modernized, designed to operate at a higher “level of service” than today’s design standards call for (technically, LOS C on rural Interstates and LOS D on urban Interstates). If a state has not yet replaced its per-gallon fuel taxes with a standard mileage-based user fee at the time Interstate tolls are introduced, the AET system will permit rebates of fuel taxes generated by the miles driven on the tolled Interstates, thereby avoiding “double taxation.”

The study also explains why per-mile tolling is a better highway user fee than per-gallon taxes. The reasons include:

  • Per-mile tolls can be tailored to the cost of each road and bridge, rather than being averaged across all types of roads, from neighborhood streets to massive Interstates; this ensures adequate funding for major highway projects like Interstate reconstruction and modernization.
  • Per-mile tolling reflects greater fairness, since those who drive mostly on Interstates will pay higher rates than those who drive mostly on local streets.
  • If per-mile tolling is implemented as a true user fee, it will be self-limiting, dedicated solely to the purpose for which it was implemented (and enforceable via bond covenants with those who buy toll revenue bonds).
  • Per-mile tolling will guarantee proper ongoing maintenance of the tolled corridors, since bond-buyers and other investors legally require this as a condition of providing the funds.
  • Per-mile tolling also provides a ready source of funding for future improvements to the tolled corridor.
  • Toll financing means needed projects, such as reconstruction and widening, can be done when they are needed, and paid for over several decades as highway users enjoy the benefits of the improved facilities.
  • Finally, a per-mile tolling system using AET can easily implement variable pricing on urban expressways to reduce and manage traffic congestion.

Converting from the 20th-century Interstate 1.0 to a toll-financed Interstate 2.0 would be a major change, which elected officials may be leery of leading. That’s why it is critically important that one pioneering state step forward to be a role model for the others. Currently, federal law prohibits tolling for reconstruction of Interstates—except for a three-state pilot program. However, all three slots are now occupied by states that have not solved the political problem of getting legislative approval to go forward. And the pilot program permits only a single facility in each (e.g., I-95 in North Carolina) to be rebuilt using tolls. This situation could be changed by Congress in the 2014 reauthorization of the federal surface transportation program. The one needed step is to “mainstream” the tolled-reconstruction pilot program, so that it is (1) available to all states, and (2) applicable to all of a state’s Interstate facilities.

America needs a second-generation Interstate highway system. The 20th-century fuel tax system is inadequate for this trillion-dollar task. This study shows that the alternative of financing this transformation via all-electronic tolling is feasible. The one needed enabler is permission from Congress to begin this transition.

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