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The American Road and Transportation Builders Association estimates that there are over 4 million miles of roads in the United States (U.S.) with the majority (approximately 77%) maintained by local governments [1]. State Departments of Transportation (DOTs) manage approximately 19% of the miles, comprised largely of high-volume facilities such as Interstates and other highways. The remaining 4% of the road system in the U.S. is managed by the federal government, which is responsible for roads in National Parks and Forests, military installations, and other federal facilities. These transportation agencies manage and maintain the pavements bridges, culverts, signs, signals, guardrails, tunnels, and many other ancillary assets that keep people and goods moving in a safe and efficient manner. Other transportation modes, such as transit and ferries, are also important parts of the U.S. transportation system. These alternate modes of travel are also managed at the federal, state, local, and regional levels.