Great points. If they need more money for the infrastructure on interstates, why not do what we do in Chicago and charge tolls, i.e. a user fee?
They also do it in downtown New York – I
Maybe this was the cause of the bridge collapse, maybe it wasn’t. We will find out when they officially say what caused it. Until the official cause is determined, what caused it will remain a question. In any case, Illinois (and I am sure other states also) is supposed to step up bridge inspections and close any bridge during construction. I don’t know if that is possible becuase closing an major highway in this area would cause more traffic on already backed-up roads.
First, call me very skeptical about this. The acid formed is very weak and once it has been reduced chemically, its dried remains should shield the steel from further damage from subsequent droppings.
Second, using the word guano is incorrect unless a pigeon is a bat or seabird. Using an incorrect word tainted the accuracy of the rest of the article.
Like most major failures, the bridge collapse will probably be the result of a series of smaller contributing factors. Remember the plane crash in, IIRC, the Everglades that was the result of a $0.10 light bulb? The cockpit crew was so worried about the indication (or lack thereof) from the landing gear light that no one noticed the plane was losing altitude until it was too late.
As far as the pigeon poop, maybe this is a job for the Mythbusters. Plausible is my guess. BTW, didn’t they once do an electochemical experiment about the effect of salsa on the steel bars in a jailhouse?
Jay
I would not be surprised if pigeon poop caused corrosion. Even the spiders might have contributed some detriment with their digestive products. And there would be other types of birds as well, no doubt. Speaking of guano, the bridge was also probably home to a large numbers of bats. I can attest to the fact that bat urine will take solid color stain finish right off of a house. I would assume that the inspectors were not only prevented from seeing the steel because of all this icky stuff, but they also probably felt that it was unfair that they should have to be exposed to it.
It has also been suggested that a de-icing system installed a few years ago that might have caused chemical corrosion. And of course road salt has been implicated as a cause of corrosion. But even though all of this could have been part of the cause, it was the responsibility of the inspection authority to learn the factors leading to a collapse and prevent it. The one good thing about corrosion is that it gives you time to catch it.
So it all comes down to this question:
Why is the public being offered these explanations for a possible cause?
There are two possible answers:
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Inspection authorities are demonstrating diligence in probing the cause, making an honest effort to satisfy the public’s need to know with as much information as possible.
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Inspection authorities are making a smokescreen to obscure the fact that they failed to perform their job.
If number two being the correct answer is not obvious, it can be arrived at by eliminating answer number one. These inspection authorities are always telling us that they cannot speculate about a cause. They must let their investigation run its course, and it might take a year or more. The new b
I wonder what the rate of highway bridge failures is as compared to the rate of railroad bridge failures.
Obviously, there are many more highway structures, but I can think of three or four modern highway failures and no comparable railroad problems (burned bridges don’t count).
Is the premise of a much greater failure rate for highways correct, or am I just remembering selectively?
Perhaps the Minnesota DOT would have us believe railroads don’t attract pigeons and spiders as highways do!
I personally think the basic design of the bridge in the first place contributed to this unfortunate tragedy.
If you’ve seen the pictures of the bridge pre-collapse, note the following:
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The spindly structure of the steel lattice framework beneath the roadbed.
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The steel is exposed to the elements (note several spots of rusting, especially around the rivet joints).
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The entire bridge over the Mississippi is held up by four very small concrete posts.
I’m surprised the bridge didn’t collapse years earlier. I do see the replacement bridge to be more a traditional reinforced concrete arch structure, something that has lots of structural strength and weather resistance to start with.
Hmm…last I heard (few days ago in various media) here in MN, was that the contractor doing construction on the bridge was being looked at, for overloading the bridge with equipment, materials, etc…hmmmm…
At the time of the collapse, there was 288 tons of equipment and supplies that was placed on the bridge by the contractor who was working on the bridge. I wonder what their contract stipulated in regard to the weight of equipment and materials that was permitted to be placed on the bridge during this work. Perhaps the contractor exceeded the stipulation, or maybe the stipulation mistakenly allowed too much weight. Or maybe there was no stipulation.
I overheard someone on talk radio screaming about how the MDOT was responsible because they funded the construction of a “useless” light rail system for the Minneapolis/St. Paul region, and could have used that money for upkeep of the bridges. While disagreeing with the main principle, there is some truth that maintenance and upkeep are the step-children of the transportation budget in most cases. It is tough enough to get tax funding for new roads and bridges where they are needed. Mass transit is often demonized as a waste of money, many voters will reject funding it if they don’t think they would use it. But I am sure that a few more folks in Minnesota may be considering it now.
Not really (MN mass transit). The main “problem” in MN regarding metro roads, transit, etc. is that the Metro area is the only part of the state that it pertains too.
I.e., every year or so, the legislature comes up with a multi-million dollar transit project, be it new construction, repairs, mass transit or whatever. Of course, such projects require more taxes, etc. usually.
If you’re not familar with MN, outside of the metro area, it is basically a rural state. A very BIG, in area, rural state; the metro area is a small part of overall MN. In terms of mindset, lifestyle, etc.
Very few non-metro MN residents, myself included, get excited about having to pay for the metro areas transportation projects. They want it, they can pay for it in other words.
And so many times, such projects don’t happen.
Exactly. Haven’t heard any more details; been to busy.
There is a lot of controversy over the issue of Minnesota transportation dollars going to non-road uses. It is pretty obvious that most of the political class in Minnesota are New Urbanists, and as such, they hate private automobiles and highways, and love light rail and bicycles. What seems to work for them is to let highway construction and maintenance fall behind so there is always a public clamor to fix it, and in exchange for promises they make to fix it, they get the tax funds to divert to their favorite darlings.
So broken highways and traffic jams are their golden goose. They feed the goose deferred highway maintenance and the goose lays golden eggs for light rail and bicycle trails. Apparently, in the case of the bridge collapse, they got a little careless about what they fed the goose. Broken highways and traffic jams are the perfect goose diet, but a bridge collapse should not have been on the menu because they guaranteed the bridge would not collapse.
I hear what you’re saying, but if there’s anything to learn about this collapse, it’s the fact that we shouldn’t jump to conclusions about lack of maintenance $, etc. being the cause.
If the contractor overloading the bridge turns out to be the “final” cause of the collapse, lack of maintenance $, etc. had nothing to do with the bridge failure.
I absolutely agree, but just to be clear, I am not jumping to a conclusion that a lack maintenance funding had anything to do with the cause. In fact I insist that such a cause would be impossible. Stopping the required maintenance for any reason while leaving the bridge open for public use would be criminal negligence. So a lack of funding cannot possibly enter into the equation.
My previous mention of funds being diverted was not to suggest that diverting funds shortchan
[quote user=“Bucyrus”]
I absolutely agree, but just to be clear, I am not jumping to a conclusion that a lack maintenance funding had anything to do with the cause. In fact I insist that such a cause would be impossible. Stopping the required maintenance for any reason while leaving the bridge open for public use would be criminal negligence. So a lack of funding cannot possibly enter into the equation.
My previous mention of funds being diverted was not to suggest that div