Lessons From the Bridge Collapse in Minneapolis?

I grew up just a few miles from the bridge that collapsed in Minneapolis. We were a family that was terrified of heights. At least once a month, my father would mention how he thought a bridge over the Mississippi was going to collapse. We would be calling him Nostradamus today, except that his doomsday prediction was about a different bridge (the old Lake Street Bridge, for those who know the Twin Cities). In fact, when officials tried to demolish the Lake Street Bridge to make way for a new one, the first round of explosives proved inadequate — they had to bring in a second round to bring it down. So that bridge proved sturdy, despite my father’s premonitions.

But what, if anything, can we learn from the recent bridge collapse?

One thing I suspect we will learn about is the government’s response to tragedy. No doubt there will be a lot of time and effort spent on extra bridge inspections, and probably a lot of money wasted because no one wants to be at risk for blame if something like this happens again. Now, I’m not saying we shouldn’t spend money on bridges; indeed, my friend Tom Paper (who also grew up in the Twin Cities) at Data360.org sent me this link to a chart depicting U.S. government spending on infrastructure as a share of GDP, which has fallen from 3% in the late 1960s to 2% currently. I’m not sure how much of that 1960s spending was put towards building interstates. But my guess is that the money spent in the wake of a tragedy like this one is not spent well.

Something about the events following the bridge collapse that makes sense, but which I never would have thought about, is how a sharp rise in cell phone usage alerted T-Mobile that something had happened before they heard the news reports. This would seem to hint at strategies that could be useful for coordinating quick emergency response more generally, as well as military/intelligence applications.


Why should the government spend money on infrastructure? Surely the free market will cause corporations to step in to avert failures that could cause an increase in their costs.


Making roads safer for bicyclists reduces injuries and deaths for not much infrastucture $.


I am sorry but if the gov didn't spend the money on infrastructure, I would totally ignore State troopers!

The cell phone spike question is a very good one and I would imagine that the AP probably has someone on that at all times. (Cell phone spikes)


Apparently, we need to replace a few bridges across MN: http://www.startribune.com/10204/story/1341088.html


About cell phones being used to coordinate emergency response- good idea, but surely there are a number of possible false positives?

Isn't it possible that the T-Mobile people just suffered from a sort of confirmation bias? It's possible that these spikes happen relatively frequently, but that after this particular one happened, they selectively remembered "knowing" something was wrong. (It's similar to how some people claim they can predict the weather through, say, their arthritis- they remember the times they had boneaches before a storm and forget the other times their bones ached).


"But my guess is that the money spent in the wake of a tragedy like this one is not spent well."

I would argue that whether any problem bridges are identified, the government is purchasing peace of mind right now. I agree that it is not money well spent if people are rational and more spending would only help identify problem bridges. On the other hand, if people are frightened and reactionary (which they are), this is money well spent calming the public.


I struggle with what our interest in this story really is? Is it about the loss of life? If so, in comparison to starving children or other deaths that occur everyday, it's quite minuscule. Not to discount the tragedy but it seems to me this is more about rebar and concrete than the loss of life. Certainly the sensational nature of the disaster intrigues us but in terms of loss of life, there are many other tragedies much more horrific than this.
I'm not suggesting we don't examine and consider solutions but in terms of priorities....it's quite far down the list.


One question in whether or not to spend money on infrastructure is the question of which investments are worth it. Some research indicates that money spent on roads is in general a poor investment. E.g., research by Cliff Winston at Brookings and others concluded that the economic benefit from highway investments is plummeting: from 17.6% annual return in the 70s to 4.9% in the 80s and to 1% in the 90s. The authors attribute this decline to several factors, including Congressional earmarks and failing to charge people appropriately for the costs they impose in using roads. Other research indicates that costs of infrastructure are very frequently underestimated and benefits overstated-this pattern is so common that researchers say it can only be explained by "strategic misrepresentation", i.e., lying. So it makes sense to require careful cost-benefit analysis to avoid the many expenditures on wasteful projects.
Chad Shirley and Clifford Winston, “Firm Inventory Behavior And The Returns From Highway Infrastructure Investments,” Journal of Urban Economics, Volume 55, Issue 2 (www.sciencedirect.com), March 2004, pp. 398-415.
This article reports on research that shows that large scale projects that get built are generally those with: underestimated costs, overestimated revenues, underestimated environmental costs and overestimated economic benefits.

Flyvbjerg reports on a study by Wachs in which he says that "in case
after case, planners, engineers and economists told Wachs that they had had to "cook" forecasts".




It's not just in the US where extra resources and money are being spent: http://news.bbc.co.uk/1/hi/magazine/6929777.stm details how the UK Highways Agency is now going to spend extra resources looking at the bridges in the UK (even though they have confirmed that none of them are the same construction as the one that colapsed).
Does this mean that they needed to spend more looking at bridges in the first place or just your Atlantic cousins following suit?


All of the resources and effort spent on the investigation are definitely worth it. While some waste may happen with regard to CYA and blame deflection, I think the largest benefit comes from the fact that there are hundreds of thousands of bridges in the US (not to mention the rest of the world) and likely hundreds that have some important similarities to the one that failed in Minneapolis. Failures like this one sometimes identify problems with a particular class of bridge that were previously unknown or whose risk level was not properly assessed. Perhaps microscopic cracks in the steel were considered to be a mild risk to be monitored, but this will discover that if they exist near a particular location in the bridge that they need attention. Or maybe they'll identify a problem with how recent work was done which will change procedures in future related bridge maintenance. They may find none of these, but given the number of bridges involved, and the lack of understanding of the failure, this is money well spent.



I utterly disagree with the cynicism of this post- this really is the perfect time to buttress infrastructure spending- it's the wisdom of looking at what good can come out of this tragedy- presuming that spending outlays are cyclical, and that the bean counters can always argue for and against any spending projects, what better way to shift public spending than when public sentiment is high?- the spotlight is now on government neglect of infrastucture- so let's work at improving it and we'll all feel better about the ramifications of this event

Big Hal

"Isn't it possible that the T-Mobile people just suffered from a sort of confirmation bias?"

Possibly but telephone traffic is fairly predictable so abnormal traffic shows up fairly distinctly. When I worked in a long distance call center operators would routinely ask supervisors if something was going on in various places based on the number of calls they were handling from and to a given area.

The problem of course is identifying the cause of the spike. The classic example is the radio station giving away a $1000 dollars to the 26th caller. Generally those sort of spikes are of fairly limited duration though.


Infrastructure in America is going to be a bigger problem in years to come. We have taken for granted all the building that happened in the post-war years. Our patterns of life have become dependent on structures that we think are permanent, but in fact are coming to the end of their useful life. It's no coincidence that our freeways and sewer systems are getting decrepit just as the baby boomers are - we were all made around the same time.

When we think about the legacy we leave our grandchildren, we need to think about leaving them a country in good working order.


pparkman, I couldn't agree more. What about public transportation? Can we not upgrade and improve that infrastructure? Or are we too afraid we'd be giving terrorists better targets?


The lesson here is that the governing body spending money on new infrastructure should be required by law to appropriate money to maintaining that infrastructure for the predicted useful life of the project.

Or voters who use infrastructure projects should reward candidates who maintain those projects over candidates who build new projects.


Angry Bear blog has details of spending by President.

Reagan, Clinton and GWBush are the 3 making the cuts.
While GHWBush merely sustained Reagan's cuts.

Why am I not surprised?

Our current gov in MM - Pawlenty - pledged to Never Raise Taxes. Kind of a box for him at the moment.

If you look at the list of deficient bridges linked in Post 4 above you will see the 35W bridge over 62. That is actually an interchange with bridges over city streets and the replacement started this summer. There is a bit of a sad-joke story about the project.

The state did not have the funds but had decided to do the project. So 2 years or so ago they put the project up for bids with NO FUNDING. They asked the contractors to Trust that the state would come through the following year. Guess what? No Bids.

So they finally borrowed enough and got going this summer.

I have no clue how the state will fix the rest of the listed bridges.

NOTE also: How few of the bridges got inspected in 2006 vs 2005.



to find Angry Bear posting go here:

(I hope the link comes through in one piece.)


We should be careful to separate the basic issues. One is that unsafe bridges should not be kept open (unless travelers are specifically warned -- I don't much care if someone who knowingly crosses a defective bridge gets hurt; that's their lookout). It's negligent to leave an unsafe bridge open, whether it's publicly or privately owned. So if the government doesn't want to pay to keep all the bridges safe, some of them need to be sold, given away, closed, or demolished. That's common sense.

Regardless of whether bridges are public or private, or whether infrastructure spending should be increased or decreased, anyone who maintains the pretense that an unsafe bridge is safe is indulging in negligence.

As for making a big show out of closing the barn door after the horses have escaped, who is going to be fooled by this? Bridge safety is a highly technical, long-term proposition. Politicians can do nothing useful in the short term other than closing the most dangerous bridges. I predict they will prove very reluctant to do this, due to the inevitable uproar. So most of what will be done will be fake. Hopefully the civil engineers will get more mindshare for a while, though.



In case you're not aware of it, the Lake Street Bridge DID collapse. One section of the new one, which is of concrete arch construction, collapsed during construction because the concrete form for the arch was insufficiently supported. IIRC, there was one fatalaty.


This is when one can really identify how government truly works.
It isn't about return on investment, in terms of comparing the benefits society gains as a result of society's money(taxes) spent. It is about return on investment, in the terms of how many votes will I Senator John Doe get next election as a result of a government spending project I sponsor.
Government spending on roads is not popular, because it really doesn't win you votes in an election, unless of course the roads reach critical mass and an infrequent event occurs that scares people enough to believe that their vote might need to be bought through government infrastructure spending. Although, human beings have terrible memories, so I doubt this will go very far.