The U.S. Department of Transportation’s (DOT) Bureau of Transportation Statistics recently released the latest Transportation Statistics Annual Report, which includes figures on employment, bridges, roads, inspections, fatalities and more.
Various agencies within the government have accumulated information for the annual report since 2013. Not all of the categories are analyzed on a yearly basis, which is why some of the figures may be from 2011 or 2012.
The report states that as of 2012, there are 4.1 million miles of public roads within the U.S, an increase of 2.8 percent. Of the miles, 47,400 are interstate highways, which amounts to just 1.2 percent of U.S. roads. This small percentage belies the fact that these interstates frequently have the highest traffic volumes of any roads within the U.S.
Analysts used the International Roughness Index (IRI) to determine the conditions, smoothness and roughness of roads and bridges. An unsatisfactory rating with the IRI is 170 or more; 35.3 percent of U.S. urban roads and 13.9 percent of its rural roads were reported as having an IRI rating of 170 or more. In 2011, the IRI stated that the all-road categories, omitting urban collector roads and urban minor arterials, improved their ratings between 10.4 and 15.8 percent.
Further report details can be found online.
