Nearly 70000 (11.5%) of bridges in the US are deemed structurally deficient and need significant rehabilitation, while federal and state governments are not spending enough to keep the numbers from growing, according to a new report by T4America.
The report, The Fix We're In For: The State of the Nation's Bridges, by Transportation for America, says, "For bridges, lack of maintenance can lead to the sudden closure of a critical transportation link or, far worse, a collapse that results in lost lives and a significant decline in regional economic productivity."
The report cites the US Federal Highway Administration (FHWA), which estimates that the backlog of potentially dangerous bridges would cost US$ 70.9 billion to eliminate. Federal spending for bridges amounts to slightly more than US$ 5 billion per year, says the FHWA.
The report ranks US states in terms of the overall condition of the its bridges, with one being the worst, 51 being the best. Twenty-three states across the US have a higher percentage of deficient bridges than the national average of 11.5%.
The five states with the worst bridge conditions have over 20% structurally deficient bridges: Pennsylvania has the largest share of deteriorating bridges (26.5%), followed by Oklahoma (22.0%), Iowa (21.7%), Rhode Island (21.6%), and South Dakota (20.3%).
At the other end of the spectrum, five states have less than 5% of their bridges rated structurally deficient: Nevada leads the rankings (2.2%), followed by Florida (2.4%), Texas (3.0%), Arizona (3.0%), and Utah (4.5%).
"Since the 2007 collapse of the I-35W bridge in Minneapolis, Americans have been acutely aware of the critical need to maintain our bridges," said James Corless, director of Transportation for America.
That need is "growing rapidly", said the report, as the average age of bridges passes 42 years for bridges that mostly were designed to have a 50-year lifespan before reconstruction or replacement.
"As Congress takes up the next six-year transportation bill, it is imperative that we devote a larger share of funding to protecting our bridges" said Mr Corless.
"Americans also want to see more accountability for maintaining our infrastructure: 64% of voters say that the way government currently spends money on building and maintaining our transportation infrastructure is inefficient and unwise, according to a February poll for the Rockefeller Foundation."