Collapse

This week everyone has been talking about the collapes of the 35W Bridge in Minneapolis, which was a very tragic event. I have been over that bridge at least a couple times over the last several years when I have been in Minneapolis. I have friends and relatives who live in the Twin Cities who could have been on that bridge when it collapsed, but as far as I know they were not. We can praise God that the anticipated number who perished is much lower than initially expected.

Now comes the investigation period. How did it happen? Why did it happen? Who was at fault? I am sure by incorporating video footage, forensic evidence, and circumstancial evidence (loads, temperature, etc.) that the first two questions will be answered fairly conclusively.

The last question is the one that could continue for a long time--"who was at fault?" I am guessing there will be a lot of finger pointing. The government will probably blame the engineers, and the engineers will blame the government. There will be a lot of finger pointing within each group as well. Of course everyone will want to pass on the responsibility. And in reality, the responsibility does not likely rest on one individual and is probably shared by many. Many times engineering decisions are not based solely on observed data, but are tempered by financial and political considerations. Too often significant repairs are not undertaken because the cost is great and useful service of the entity will be diminished or closed while work is being done.

I have absolutely no basis for assuming the following scenario, but this is a situation that I imagine could have happened. I imagine a meeting where bridge inspectors reported their findings to a group of decision-makers. They probably said that the bridge had some deficiencies that needed to be corrected. The people controlling the budget probably said that there was no money for such repairs and asked for a plan that would streamline the cost for incremental repairs, so they could be planned in the budget for years ahead. This scenario happens all the time in the engineering world. Engineers give recommendations for proper repairs, and the engineering plans are cut back to fit the budget. In some cases, this may not necessarily be a bad thing as it may force an engineer to focus on the essentials, and perhaps cause him/her to think outside-the-box on how to accomplish the goals in a more cost-effective manner. (I am sure we can all think of times when a "Cadillac" solution has been suggested when a "Kia" would be sufficient.) However, when budget constraints overpower sound engineering judgment, the consequences can be devastating. We probably won't really know what happened in this case for many months, but we all can learn some lessons here.