We Americans love our pavement. We drive 3 trillion miles a year on more than 4 million miles of U.S. roadways. Clearly we're a nation on the go and we expect our roads, streets, and highways to be available and ready whenever, and wherever, we are.
But it doesn't come cheap—in 2006 U.S.'s capital outlay for road and street construction was nearly $21 billion, and the government spent another $19 billion on roadway maintenance. With demand increasing and budgets shrinking, it's time for sober reflection on how to get the biggest bang for every buck.
Today roughly 2.6 million of the nation's 4 million miles of roadways are paved. Of that, 94% is asphalt or has an asphalt surface. But traffic has risen to levels far beyond what many roadways were designed to handle. Increases in the number of vehicles and the size and weight of trucks have led to severe deterioration in many roadways.
As the nation wrestles with a challenging economic environment, it also is facing the fact that much of its highway transportation system is in serious need of rehabilitation, even as the need for expansion continues to grow. How do we cope? What opportunities might this offer? As often is the case, a look back may help us see our way forward.
Clear and sturdy pathways always have been desirable. Whether walking or riding, no one wants to get stuck in the mud. Although numerous methods for maintaining good surfaces had been used throughout the centuries, with the coming of the Industrial Revolution alternative solutions began to emerge.
Asphalt paving was used in Europe for footpaths in the early 1800s, and by mid-century was used for roadways. By the 1870s, asphalt roadways had come to the United States, where new ideas and a can-do spirit were in abundance.
“In 1876, Belgian chemist Edmund DeSmedt supervised the asphalt paving of Pennsylvania Avenue in Washington, D.C., and in 1891, George Bartholomew paved Main Street in Bellefontaine, Ohio, with concrete,” wrote Lester Hoel and Andrew Short in the Transportation Research Board's “The Engineering of the Interstate Highway System.” Two years later, the country's first brick road paved Wooster Pike, near Cleveland.
Meanwhile, with the invention of the “safety” design in 1884 and pneumatic tires in 1888, bicycles had become a practical mode of transportation. Bicycling clubs became powerful pressure groups and, in 1892, the League of American Wheelmen began publishing Good Roads, “an illustrated monthly magazine devoted to the improvement of public roads and streets.”
Paved roads grew in number within American cities, but by 1915 most of the nation's 2.5 million miles of rural roadways still were dirt. Only 257,000 miles were surfaced, and only a little more than 14,000 miles had a high type hard surface—10,500 of bituminous, 2300 of concrete, and 1600 of brick. Meanwhile, a variety of factors, including Henry Ford's Model T in 1908, were raising popular support for improved roadways. Indeed, in 1909 the first mile of concrete rural road was constructed in Wayne County, Mich.
By 1920, American cities had a total of 365 million square yards of asphalt paving in place, but the light, water-bound stone roads were suffering even from the traffic of that era. In 1930 Harry Greene, later of Barber-Greene fame, unveiled his bituminous paver that took in heated asphalt at one end and left a lane width of pavement at the other, and asphalt paving took a step forward.
In the late 1930s, concrete became the pavement of choice for the new Pennsylvania Turnpike, which was constructed on a partially completed railroad roadbed. The 160-mile tollway featured two 12-foot-wide lanes in each direction separated by a 10-foot median. By 1939, 50 crews were on a tight construction schedule to build 3½ miles per day of the ribbon of concrete through the Allegheny Mountains. Opening in the fall of 1940, the Pennsylvania Turnpike provided many approaches and concepts that later would be used to construct the Interstate system.
It wasn't until 1954 that commercial production of a slipforming concrete paving machine began. Designed in 1946 by Iowa highway engineers James Johnson and Bert Meyers, the paver was manufactured by Quad City Equipment Co., which later became part of Rex. The technology came into the market just in time for the construction of the National System of Interstate and Defense Highways, a 41,000-mile network authorized in the Federal Aid Highway Act of 1956.
Design criteria for the Interstate system were developed in large part based on a two-year, $27 million research project set up by the American Association of State Highway Officials (AASHO, now AASHTO), the AASHO Road Test. Beginning in 1958, U.S. Army personnel continuously drove a variety of vehicles around six loops consisting of more than 800 concrete and asphalt pavement sections, including 16 short span bridges, in Ottawa, Ill. The test results greatly increased engineers' understanding of concrete's and asphalt's wearing and load-bearing characteristics, and guided highway design for more than three decades.
Over the ensuing years, the nation's highways have led to U.S. growth and prosperity. They also have taken a beating as traffic volumes and truck weights have increased. Consider this example: 2.4 million vehicles used the Pennsylvania Turnpike in 1941, its first full year of operation. By 2005, that number had skyrocketed to 188 million.
The annual number of vehicle miles traveled for the nation as a whole continues to grow at an increasing rate, compared to the growth of public road mileage, as it has since the construction of the Interstate system. The net results are a nation more dependent than ever on its highway system for the transportation of people and goods, and many miles of highways are badly in need of repair or replacement. “As the Nation moves into the heart of the 21st century, the highway system is largely a victim of its own success,” observes the Federal Highway Administration's July 2008 report “Highways of the Future.”
A rebuilding opportunity
In recent years, it has become apparent that the urgency of rehabilitating the U.S. infrastructure—perhaps most visibly its system of bridges and highways—is quickly escalating. At the end of January, the American Society of Civil Engineers released its latest “Report Card for America's Infrastructure” with the observation that since its last report in 2005, conditions have worsened for U.S. roads. Giving roads a barely passing grade of D-, the report cites chronic underfunding and congestion as two of the system's more serious but correctable challenges.
At the same time, the understanding of how to build sustainably continues to grow, and the ability to communicate and share that type of knowledge is at a higher level than ever before. The time has come for action on this front.
Now, in the wake of huge adjustments in the U.S. economy that have been a long time coming, the nation has undertaken a massive spending program that is hoped will help put America's infrastructure on the road to recovery. The ARRA promises inclusion of a $150 billion investment in infrastructure. That represents “the largest increase in funding of our nation's roads, bridges, and mass transit systems since the creation of the national highway system in the 1950s,” according to Recovery.gov, the government's Web site that helps citizens track funds allocated through this legislation.
In planning this program, then President-elect Obama challenged local leaders to put forward an updated list of shovel-ready projects that could be both undertaken and completed quickly. The U.S. Conference of Mayors responded with a 1500-page report, which served as the framework for the infrastructure portion of the ARRA. The report at that time included 11,400 projects (it now has grown to 18,000) in 427 cities that could start quickly and finish by the end of 2010.
Funds are being dispersed through the individual states, which have a great deal of discretion in how they are applied. However, because the primary motivation behind this act is to get the economy moving again, states have just 120 days (until mid-June) to assign funds to specific projects. As a result, many of the highway-related projects now being funded are for smaller, less complex programs that are relatively easy to launch, such as maintenance and upgrades.