Worst off were the nation's levees and inland waterways: Each got a D- from the engineers' group.
Solid waste, drinking water, wastewater, roads, and bridges all saw slight improvements from four years ago, and no sector got worse.
"While the modest progress is encouraging, it is clear that we have a significant backlog of overdue maintenance across our infrastructure systems, a pressing need for modernization, and an immense opportunity to create reliable, long-term funding sources to avoid wiping out our recent gains," the ASCE report said.
It noted that the nation would need to spend $3.6 trillion by 2020 to bring U.S. infrastructure into good repair.
State-by-state analyses were not as current as the national assessment.
A 2010 report card for Pennsylvania gave the state a C-, with the dubious distinction of having the highest percentage (24 percent) of its bridges deemed structurally deficient.
A 2007 report card for New Jersey gave that state a C- as well, with $8 billion needed for drinking-water improvements and $32.5 billion needed for improvements to wastewater-treatment facilities. And that was before Hurricane Sandy hit the state.
"A report card grade of a D+ is not indicative of a first-class infrastructure," said former Pennsylvania Gov. Ed Rendell, now a co-chair of Building America's Future, a group that advocates for increased spending on infrastructure. "For America to stay competitive in a global economy, we must significantly improve our energy, transportation and water systems."
The report is available on-line at www.infrastructurereportcard.org.
Contact Paul Nussbaum at 215-854-4587 or email@example.com