Investment in bridges continues to fall well short of needs, despite widespread agreement that our national bridge infrastructure is failing and in desperate need of attention. Unfortunately, the problem is often ignored until it is already too late, putting lives at risk and ultimately costing more money in the long run because of the economic costs of decaying infrastructure.

A recent short documentary by The New York Times in collaboration with Retro Report, a nonprofit video news group, highlighted the danger of ignoring bridge infrastructure. The video revisits the tragic collapse of the I-35 W bridge in Minneapolis in 2007 that killed 13 people and injured nearly 150 others. Though this bridge had been rated in poor condition for 17 straight years by inspectors, its repair was continually postponed.

In the documentary featured below, Tom Johnson, author of the report on the I-35 bridge’s collapse for the Minnesota state legislature, identified the reason repairs were postponed as a lack of funding, not a lack of awareness. “We came away from our investigation that these are professionals trying to do their job, but they had some very severe restrictions about what they could do, largely because of lack of money”, he said.

While the I-35 tragedy put the issue of bridge safety in the national spotlight and led to numerous pledges that bridge inspections and repairs would be given priority and funding, these promises have largely rung hollow.

Last year, in their national infrastructure report card, the American Society of Civil Engineers gave the nation’s bridges a grade of C+, a slight improvement from the score the society gave bridges four years earlier. The ASCE notes that one in nine of the nation’s bridges are “structurally deficient” and that the average age of the nation’s bridges is 42 years.

Transportation experts agree that the gap between actual and needed investment in bridge infrastructure is vast. According to estimates by the Federal Highway and Safety Administration, fixing all the nation’s deficient bridges by 2028 would require $20.5 billion in investment annually, while the country is currently only spending $12.8 billion annually. Similarly, the National Bridge Inventory estimates that the backlog of structurally deficient bridges is $121.2 billion (in 2008 dollars) and that if 2008 levels of bridge investment remain flat through 2028, this backlog will only be reduced by 11.2 percent.

Bridge repairs and other types of infrastructure investments, especially maintenance, are often delayed for two reasons:

The first is that bridge repairs are often extremely costly and can amount to hundreds of millions of dollars. This is a particular problem in the current climate of fiscal austerity where federal, state, and local budgets are tight. With regard to bridges and highways, the ever-shrinking Federal Highway Trust Fund, which is funded by gasoline taxes, poses a long-term challenge. With better gas mileage and the lack of political interest in raising gas taxes, the fund is growing smaller.

The other reason is that investing in infrastructure doesn’t usually grab enough headlines for ambitious politicians. As The New York Times puts it, “How many elected officials are just dying to preside over a ribbon-cutting ceremony for a new gusset plate?”

But failing to maintain bridges costs the economy. In a Wall Street Journal article last year, business owners spoke of how deferred maintenance meant higher costs for them. For instance:

Donald Maier, senior vice president for a Lancaster, Pa. firm making floor and ceiling tiles, reported that a fully loaded truck trailer traveling to or from its Marietta, Pa., ceiling tile plant would have a 25-mile detour to avoid a two-lane state highway bridge will no longer accommodate fully loaded heavy-duty trucks. The company projected the additional miles would add about $200,000 to $300,000 a year to the plant’s transportation costs.

Investing in bridges may be expensive, but the costs of not doing so are even higher, especially when human lives are at stake. In a country with the wealth and resources of America, failing to invest in bridges just doesn’t add up.