In wake of the recent tragedy in Minneapolis on I-35 last week, many are still asking questions about the quality of Oklahoma's bridges. Are we at risk? What's the lifespan of a bridge anyway? ODOT reports that of the 6700 bridges in Oklahoma, 1600 are functionally obsolete or structurally deficient.
The bridge that collapsed into the Mississippi River in Minnesota was an arch steel deck truss bridge and ODOT officials say there are 62 county bridges that are fracture critical and of those, 15 are a very similar type of bridge to the one that collapsed in Minnesota. One is in Comanche County, a "pony truss" bridge. Luckily it has been closed since 2003. There's also one in Caddo County and three in Jefferson County. And some of these Oklahoma bridges have been around since as early as 1918 according to our Oklahoma Department of Transportation expert Gary Ridley.
Originally, highway bridges were made for less of a load than they carry today and several decades ago most families only had one car. Last year, ODOT celebrated 50 years of a successful world-known interstate system, which Gary Ridley feels is both good and bad. Fifty years is a long time, and the bridges are beginning to show their age. "I think anyone can see the amount of truck traffic has exploded for the last 20 30 years," Ridley says. "And what's really scary is freight movements will double over the next twenty and triple over the next 30."
Ridley thinks about highway and bridge safety every day, but he says there's a funding crisis nationwide - not just in Oklahoma. "If you don't invest in infrastructure and allow it to deteriorate problems will manifest that you wish hadn't," he said. Ridley says it's important to evaluate and inspect these bridges no matter what the cost, but they will have a better idea of how much in a little over a month.