The largest portion of the federal-aid went into the existing system.
Out of $41 billion in federal-aid highway contract authority states had in fiscal 2013, only 5.9 percent was used to build new highways or bridges.
“Another 15 percent went to adding new capacity (usually, but not always, new lanes) to existing highways and bridges,” said the Nov. 10 report.
Upkeep of current systems was by far the biggest area in which states obligated federal highway funding.
Analysis of the report also finds that 8.5 percent of their contract authority to support operations including engineering, right-of-way acquisition, planning and utilities.
6.3 percent of contract authority went to safety projects, while smaller amounts went to areas including federal lands, research, enhancements and environmental work. 2.5 percent went to state or local debt service.