Highway Safety: Bridges – What is the condition of the bridges in your state, city or town?

Our goal at the InjuryBoard is to prevent injury. To prevent injury let’s examine the available data and government policies that predispose this country’s infrastructure to increased risk of injury. In this post we examine bridges in our states, cities and towns asking the question: Is your hometown beyond the sudden failure and collapse of the I-35W Interstate System Bridge in Minneapolis?

Many parents have to wonder if the bridge your family drove over during rush hour traffic or with an oncoming farm equipment is one of those bridges classified as structurally deficient. You have a right to know.

There are sources available on the Internet where you can examine the condition of bridges in your hometown. There are a couple of different ways to determine which bridges in your community are safer than others. But of course there is no way of knowing if any one bridge is likely to fail because the weight on every bridge changes by the minute. What this information does reveal to us is whether or not failure is more or less likely based on age, existing condition and design that is combined to give each bridge a rating. The ratings go from zero to one hundred with the highest rating being good. A rating below

1. Which bridges in my hometown are not considered sufficient for today’s traffic? (For an explanation of what is and is not structurally deficient or functionally obsolete see the definition below or the previous post Highway Safety - Finding information about bridge safety in your hometown.

Short Answer: Without knowing your hometown there is no way to tell, but you can check those bridges and each sufficiency rating along with the traffic numbers.

2. How do bridges in my hometown compare to the Minnesota Bridge that failed?

Short Answer: Without knowing your hometown there is no way to tell for sure, but you can check those bridges and each sufficiency rating along with the traffic numbers. After you know the sufficiency rating and daily traffic count compare it to the following information. The I-35W Minnesota Bridge is Bridge No. 9340. The bridge catastrophically failed during the evening rush hour on August 1, 2007, collapsing to the river and riverbanks beneath.  

What was the sufficiency rating of Bridge 9340?

The June 10, 2005 bridge inspection report noted Bridge No. 9340 to have critical fractures and cracking.  The June 15, 2006 bridge inspection report noted fatigue cracks in the approach decking and fatigue cracking was noted. On 8/02/2007 the sufficiency rating was a 50 per Minnesota DOT Bridge Inventory Inspection Report for Bridge 9340. Inspection reports were issued in 2005 rating the bridge as structurally deficient and suggesting replacement. See the U.S. Department of Transportation's National Bridge Inventory database. Problems were noted in two subsequent inspection reports. [42][43]

Makes me wonder whether we can trust the engineers calculations.

3. How big is the bridge problem in the United States?

Short Answer: I’m not sure anyone can really say. We have sufficiency ratings based on data but with weight on the bridges changing by the minute how can anyone really be sure of the rated condition? For the most part bridges that are unsafe are either replaced or have the use restricted.

I’ve commented in the past about how after going to law school no lawyer can ever look at the world in the same way. We know too much and little things mean a lot to us. What I’ve learned from reading about bridge safety ratings is that when you see a sign limiting the weight of trucks that are allowed to use a bridge, that’s a pretty good indication the bridge, is structurally deficient. Knowing that of the 600,000 public road bridges listed in the National Bridge Inventory, roughly 12%, or 74,000, are classified as structurally deficient, you shouldn’t be scared but you should be concerned.

So where can you check on the function and structure of the bridges you drive on? You can find the rating of any bridge in your state at the AASHTO site where the information is listed by state and hyperlinked.