It’s time to get serious about fixing our nation’s highways, concludes the Transportation Research Board (TRB). Worsening congestion damages public safety and economic growth, the TRB warns in a recent congressionally-mandated report.
“Unless a commitment is made to remedy the system’s deficiencies and prepare for these oncoming challenges, there is a real risk that the nation's interstates will become increasingly unreliable and congested, far more costly to maintain, less safe, incompatible with evolving technology, and vulnerable to the effects of extreme weather,” says the report.
TRB is a division of the National Academies of Sciences, which co-sponsored the report along with the U.S. Department of Transportation (DOT).
“The interstates have long been the backbone of our country’s transportation system, but most of them have exceeded their design lives and in many places are worn and overused,” says Norman Augustine, former chairman of Lockheed Martin Corp. and chair of the committee that wrote the report. “These aging interstates are highly congested oftentimes and in need of reconstruction.”
Infrastructure funding, the lion’s share of which is spent on highway construction and maintenance, enjoys widespread bipartisan support even in this age of political polarization. The only real roadblock to a new program being swiftly adopted is the lack of any kind of agreement on the funding source.
For example, more than one-third of interstate bridges have been in service for more than 50 years and will require repair and renewal investments that will add significantly to the major outlays required for rebuilding the system’s original pavement foundation.
The report calls for a 20-year “blueprint for action,” which includes Congress acting to create an “Interstate Highway System Renewal and Modernization Program (RAMP),” increasing the federal fuel tax to help pay for it, and allowing tolls and per-mile-charges on more interstate routes.
TRB says RAMP would reinforce a partnership where the federal government would provide leadership, vision and the bulk of the funding, and the states would prioritize and execute projects in their traditional role as the owners, builders and maintainers of the system.
The report also notes that advances in technology—ranging from more efficient and faster construction methods and more durable materials to electronic tolling and increasingly connected and automated vehicles—could make the rebuilding of the Interstate Highway System and the allocation of its capacity more manageable, while also furthering the continual goal of increasing the system’s capacity and level of safety.
Augustine points out that technological advances are offering new opportunities, but may also undermine a principal source of income for the interstates, namely the tax on fuel, which hasn't been increased since 1993. “We recommend a course of action that is aggressive and ambitious, but by no means novel. Essentially, we need a reinvigoration of the federal and state partnership that produced the Interstate Highway System in the first place,” he says.
The TRB report adds, “Lifting the ban on tolling that applies to most general purpose interstate lanes would provide states and metropolitan areas with more options for raising revenue for their share of RAMP investments and for managing the traffic demand on and operations of interstate segments that offer limited opportunity for physical expansion.”
Rough Pavement Ahead
Between 1980 and 2015, vehicle miles traveled on interstates grew by more than 160%, compared with a 90% increase on all other public roads. Interstate highways at present are only about 1% of the total public roadway mileage in use today, but they represent 25% of all vehicle miles traveled. That includes about half the miles traveled by commercial trucks.
The board identified both long-standing and emerging challenges confronting the future of the interstates. These include rebuilding the system’s pavements, bridges and other aging assets before they become unserviceable and less safe.
Another is the need to add more traffic capacity and demand management capabilities, especially on congested urban segments. This must be designed to ensure the system’s coverage keeps pace with changes in the location of the country’s population and economic growth. Other needs include improving safety as traffic volumes increase and adapting to changing vehicle technologies.
“Large metropolitan areas are expected to continue to account for most of the country’s population growth, yet their interstates have little room to expand locally and are likely to require innovative solutions to accommodate growing travel demand,” the report predicts.
Another issue is the fact that while thousands of miles of high-quality highways other than interstates connect the country’s population centers, lack of access to the interstate system is seen by some smaller communities and emerging cities as detrimental to their growth and development. This is particularly the case given that the interstate system includes the country’s main trucking corridors and links to other modes of transportation.
Recent combined state and federal capital spending on the interstates has been approximately $25 billion annually. To renew and modernize these highways over the next 20 years, $45 billion to $70 billion will be required annually, depending on uncertainties, such as the rate of growth of vehicle miles traveled, the report observes.
TRB also urges Congress to direct DOT and the Federal Highway Administration (FHWA) to establish criteria for “rightsizing” the interstates—which would extend the system’s length and scope of coverage and seek to minimize the impact of disruptions caused by highway segments that are viewed as intrusive to local communities, such as neighborhood roads used by drayage carriers near ports.
“These criteria should be developed in consultation with states, local communities, highway users and the general public and take into account the needs of growing regions and cities for improved access to the transportation network, as well as the interests of jurisdictions that have been harmed by interstate segments that divide or isolate neighborhoods,” the report states.
TRB also recommends that Congress tell DOT and FHWA—working with states, industry and independent technical experts—to start planning for the transition to more automated and connected vehicle operations.
This should embrace the needed research and updates to Interstate Highway System requirements and standards to ensure that basic intelligent transportation system instrumentation is adopted on a consistent and systemwide basis, TRB says. It stresses that this effort should promote uniformity and other attributes of pavement markings, interchange design and the like should be capable of facilitating eventual interstate use by connected and automated vehicles.
