Did climate change contribute to the Minnesota bridge collapse?

Climate Progress: The thought didn’t cross my mind until my Minneapolis-based brother suggested it. I had asked him for his thoughts on the collapse, and that is the question he posed.…

...Why did this happen? Structural integrity will obviously be a huge concern. Minnesota experiences extreme temperature fluctuations throughout the year and this summer has been extremely hot and humid. During my time working there, road buckling from extreme heat was very common. You have to wonder if the bridge buckled.

And consider the remarkable conclusion of one Minneapolis resident: “…I am reasonably certain that authorities and investigators will find that the extreme heat of the last several days in Minneapolis had caused the expansion joints in the bridge to close completely. When this happens, the pressure building up between the sections of concrete can amount to thousands of pounds per square-inch. As the pressure goes beyond the compressive strength of the concrete, the roadway will “buckle”. When this happens on a regular highway, it is a major or minor nuisance, depending upon the size of the buckle. However, a truss bridge is a delicate balance of tension and compression in the structural components….

…Melissa Hortman of the Minnesota House of Representatives “speculated that 90-plus-degree heat Wednesday and the above-normal temperatures of the past two summers may have been a contributing factor,” and said “You wonder if this bridge was built to withstand the massive heat we have had this summer.” Or even if it was built to withstand heat, whether its structural deficiencies undermined the design integrity to a point where heat contributed to the collapse.

My brother also wonders if the low level of the Mississippi played a role…The water level has been lower but the less-than-optimal conditions” could have been a stressor. “Not a cause, but one of the myriad things that can go wrong with a bridge rated among the nation’s worst, one that has been designated ‘structurally deficient‘ since 1990.”

…Certainly climate change will have the biggest infrastructure impact on our coastal cities, water and sewage systems, levees, and electric grid. But given that a remarkable 70,000 other bridges in the country are also structurally deficient, we should seek to learn whether such troubled bridges can take the ever-growing stresses generated by global warming. We need to be as prepared as possible for a changed climate — as the Center for American Progress has previously argued. Indeed, if the adapters have their way in blocking serious efforts aimed at prevention, we’ll need to be prepared for the very worst.