August 8, 2007

Inspection Reports Show Pier Changes

Inspection reports on the St. Anthony Bridge show one of the pier supports had shifted in 1996, and made numerous observations of cracks and fatigue in the approach spans in the years since. MnDOT repaired most of these, but the bridge continued to show more significant problems in the years approaching its devastating collapse:

State bridge inspectors warned for nearly a decade before its collapse that the Interstate 35W bridge had "severe" and "extensive" corrosion of its beams and trusses, "widespread cracking" in spans and missing or broken bolts.

Not only was the superstructure in poor condition, but certain components were "beyond tolerable limits," and one of the bridge's piers had "tilted to the north," they reported.

By 2000, the inspectors wrote that "eventual replacement of the entire structure would be preferable" to redecking the bridge. They added: "If bridge replacement is significantly delayed, the bridge should be re-decked."

That recommendation was repeated in every report afterward, but it never happened.

If the inspectors recommended replacement of the bridge, that recommendation did not make it out of MnDOT. Governor Tim Pawlenty insists that MnDOT has consistently recommended replacement in 2020, and that he, former Governor Jesse Ventura, and state legislatures over the last several years relied on MnDOT's decisions in this arena. MnDOT, which did not send anyone to answer questions at the various press conferences, insist that they made repairs to specific areas of concern of the inspectors, and that replacement did not get considered because the main truss spans did not show any fatigue or cracking.

This could be true, and the bridge still could have failed. As I noted before, the design lacked redundancy, something that apparently did not get calculated into the recommendations from MnDOT. The bridge could have suffered a failure somewhere away from those main truss spans and still have brought about a collapse. Newer and older bridges have redundant supports that would prevent this, but bridges built in the post-WWII era to around 1970 did not.

One point will certainly cause some curiosity. The main truss spans connected to the piers on either end of the bridge. If one of those piers began to tilt in 1996, how could that not have affected the main truss spans? In a bridge with no redundant support structures and no center piers, wouldn't that have been a red flag?

In the meantime, plans for a replacement bridge have begun -- and have expanded beyond replacement:

Calling for a 10-lane bridge that would meet the growing demands of Twin Cities commuters, political leaders on Tuesday described a replacement for the collapsed Interstate 35W span that would be built swiftly, "right and safe."

The successor to the eight-lane bridge will be two spans with five lanes in each direction, including a transit option, Gov. Tim Pawlenty and Minneapolis Mayor R.T. Rybak said as the state moved to have eligible design-build teams for the new bridge construction in place by the end of the week.

It makes sense to build a wider bridge now rather than wait for later. The traffic over this bridge would have called for an expansion soon anyway -- at which point perhaps the flaws of the previous bridge would have become obvious -- and it will cost less to start now. An expansion will put pressure on Minnesota to expand the I-35W corridor in the southern approach, however, and there is not much room to do so. Will Minnesota have to start using eminent domain to knock down the residential neighborhoods on either side of the freeway? I-35W only has six lanes of traffic for most of the southern approach.

Also, the transit option looks like another way to siphon money out of highway-maintenance funds. We should put the light-rail pet projects aside for a while and spend our money on fixing the rest of our bridges, or replacing them if necessary. So far, Northstar has been nothing but a boondoggle serving few Minnesotans and distracting from the maintenance of highway systems that get far more use.

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Comments (18)

Posted by Cindy | August 8, 2007 7:44 AM

Cap - we are stuck with the Central Corridor. The bridge that they were talking about using for the Central Corridor is not able to handle the weight. Rather than rebuilding two bridges, why not build it into the new one. It would certainly be a more efficient way of doing it.

Cindy

Posted by Al Maviva | August 8, 2007 8:06 AM

Hmmm. So it is as the Democrats allege, all George Bush's fault. MNDot, Pawlenty, Jesse Ventura... all Bush acolytes. So too the Transportation Secretary, another Bush hack crony appointed because of his connections. Heckuva job, Minetta. Heckuva job.

/sarcasm

How they can spit out the "It's all George Bush's fault" talking point without it sticking sideways in their throat and causing them to choke to death, is well beyond my understanding.

Posted by TomB | August 8, 2007 8:07 AM

The infrastructure is getting old all over the place. When facing the costs, we have to expect more calls to "end the highway expansion madness" and replace it with "an efficient", nineteen century concept of a railway network (this time it is called "light rail", or something). Those systems never work, but do-gooders are very good in ignoring reality. Just a thought on a side ...

Posted by Halffasthero | August 8, 2007 8:31 AM

So the warnings went ignored. Why am I not surprised? And I don't think anyone was saying it was "all George Bush's fault". There is plenty of blame for everyone. As to widening the bridge, I actually like the idea. Or perhaps keep it the same and design rail to go along. It works in Chicago for the most part. There is no room to widen the Eisenhower freeway and rail runs along side. Ultimately, 35W and I-94 will follow the same fate, Eminent domain will only work in the short run.

Posted by amr | August 8, 2007 8:41 AM

I disagree with putting off a light rail/monorail system in conjunction with the new bridge. Having previously lived in San Francisco and in the region commuting to the downtown area, at one time the city with the most dense vehicle traffic, I tried driving, taking the express bus and finally settled on the BART system (light rail). I actually saved money by paying for public transportation rather than driving to and parking in the city, all things considered. And the stress was considerably less too. For those who have a routine requiring few side trips, light rail access to a city is the best method of transportation. Last month I spent 3 days in Vancouver, B.C. and traveled extensively in the city and surrounding area by their Sky Train (light rail) and bus system. I specifically picked a hotel with easy access to the Sky Train. I did the same for two weeks in Europe a few years ago.

I worked in the power industry and consider myself a practical person who relies on logic to attack a problem. I now have a small farm in a very rural area with no public transportation but if I was to return to a city, I would again utilize the public transportation systems available.

I have always marveled that we build ribbons of highways to cities having center median strips with park and ride areas and no small footprint electric monorail system running down the median. It always seems to me, having lived allover our country in the past 45 years that the more highways we build, in a short time the number of vehicles seems to multiply to fill the created space. A 10 lane highway into the Twin Cities will direct even more traffic into the same area and streets that are probably now overtaxed. Eventually we will run out of space for all of these vehicles in our cities. We need to think outside of the box we know and plan for the future when opportunity or a tragedy presents itself.

Posted by RBMN | August 8, 2007 9:12 AM

I wonder if the people evaluating the steel truss for MnDOT, and the people evaluating the concrete piers for MnDOT were the same people. And if not, were they talking to each other...enough...about how flaws in one system affect the other? Somebody was making terribly flawed assumptions about this bridge. Was it the same problem we had in homeland intelligence collection? "Stovepiping."

Posted by Al Maviva | August 8, 2007 9:25 AM

>>>There is plenty of blame for everyone

Absolutely. Which is why we should blame George Bush, and for that matter, perhaps the Pentagon, and while we're at it this guy who runs a deli in Woonsocket, R.I.

/Sarcasm (again)

There isn't plenty of blame for everyone. States and localities have to take some responsibility for themselves. Attempting to pass the buck upwards on what appears to be a string of state level screwups is fairly disgusting, and only serves to further concentrate power over local issues in the hands of the people who are least suited for dealing with local problems, the Federal Government.

Posted by Redman | August 8, 2007 9:28 AM

Isn't that nice: the politicians in your city screw-up, and now I have to pay for your bridge. And you call yourself Conservative? You suck at the same tit as Sheehan. How about refusing federal this federal gift, taking responsibility for your own bridge and cleaning-up your own house.

Posted by Gary Gross | August 8, 2007 9:32 AM

As I said here, the tax increases that seemed inevitable last weekend isn't inevitable after all. The highest priority is for reprioritizing our transportation spending.

It's encouraging to see that a solid majority of Minnesotans agree with my reprioritize & reform agenda rather than on increasing taxes.

Posted by Insufficiently Sensitive | August 8, 2007 9:46 AM

From a position of exalted wisdom in Seattle, I must protest the neanderthal concept of building the bridge wider for future traffic. All we illuminati know that it is the job of the community to PREVENT transportation alternatives that furnish choices of routing and scheduling to individuals, such as the motor vehicle. Therefore, the proposed bridge replacement must provide only half the capacity of the original, to begin the weaning process.

Better for the community to gather together such significant amounts of taxpayer capital, by whatever political means are necessary, that they may be diverted to fund mammoth public transportation schemes such as light rail. Benefits, in Seattle's experience, accrue immediately to the political class and their wholly-owned allies such as labor unions and law firms - oh yes, and to the three percent of commuters whose homes and work sites allow use of the light rail. Additional benefits include the deprivation of funds to the Highway Department, thus preventing the devotion of resources to drivers-choice-enhancing roads. This is facilitated by always denying the public a chance to vote on a choice between roads and rail - after they've been mendaciously suckered into the first vote enabling light rail, as we accomplished in 1996.

And of course, unforseen consequences of such deprivation may provide a leverage effect, such as the occasional collapse of an unmaintained bridge (a perfect lesson to those obnoxious motorists who rely on highway infrastructure), although in the case of I-35W it appears that MnDOT was in bonanza for funds and had simply allocated them elsewhere.

Bring on the light rail! Those driver whose daily commutes can't utilize it can all report to the community re-education camp (funded by the light rail agency of course) for consciousness-raising.

Posted by Dave | August 8, 2007 9:51 AM

George Bush doesn't care about Norwegian and Hmong people.

Posted by RBMN | August 8, 2007 10:17 AM

Re: Redman at August 8, 2007 9:28 AM

Redman wrote: "How about refusing federal this federal gift, taking responsibility for your own bridge and cleaning-up your own house."

Hey genius...it's part of an INTERSTATE HIGHWAY:

See:
http://en.wikipedia.org/wiki/Interstate_35

Posted by La Mano | August 8, 2007 11:29 AM

As I have been reading about the 'aging infrastructure' and the 'fractures and fatigue', 'widespread cracking', 'exceeding tolerable limits', the urgent need for 'repair and reinforcements' and even 'replacements' .............. I first thought the topic was Congress.

Posted by Ray | August 8, 2007 11:43 AM

"Will Minnesota have to start using eminent domain to knock down the residential neighborhoods on either side of the freeway?"/i>

That is exactly what happened in the 60's when I 35W was expanded into 6 lanes. There was a lot of resistance to that expansion then and there were some terrible design decisions made, like the I 35W/Highway 62 interchange which has caused incredible traffic flow problems ever since it was completed. That design itself lead to the death of a woman the first day the interchange was opened to traffic.

Since a lot of people are still dealing with the consequences of the bad planning and construction of the I 35W corridor through Minneapolis, I doubt that any further expansion will be greeted with much enthusiasm by the residents and businesses in the area, especially in Downtown Minneapolis, and there would be considerable resistance, so much so that such an expansion would not take place.

Posted by pk | August 8, 2007 12:40 PM

listen up gang:

i have been a railroad fan since 1954. and i know that a ten foot right of way will carry (in commuter mode) more people than a six lane highway.

i live about a mile from the blue line in long beach california and it is far more successful than the admittedly rosey predictions used to justify the construction. we have the red line, the blue line, the green line, metrolink etc. etc. etc. and they all suffer from the same problem. they need monstrous parking lots at the outer ends. if you want to use one during the day you better get a parking spot before 8:00 a.m. or you won't get one. a side problem is that the parking lots have to be patrolled in some areas or the local car stripping firms will make adjustments to your wallet.

yeah.

but you know that creates a bottle neck.

our current society will not stand around twiddling its thumbs waiting for the trolley especially if it does not start right at their front door and stop right at their office.

the earth huggers will tell us until they are blue in the face that we should strive for a caveman society, but we're builders and that dosen't go down with builders very well.

think about it, when the price of gasoline is down the whole country seems to "get going".

yes i know that "leading and trailing" indicators say other things (like why does the price of every thing go up when the price of gas goes up and it is attributed to fuel for delivery trucks. [nearlly all of the delivery trucks and trains use diesel fuel and that price has been somewhat at odds with the price changes of gasoline.])

like i say: even though i am a train fan, dump the light rail commuter system and build the new bridge twelve-fourteen lanes wide.

as a tip look at the overpass bridges on that same road and see if they are over lengh to allow for more lanes on the road below without having to rebuild them.

C

Posted by Redman | August 8, 2007 1:21 PM

RBMN: Pathetic attempt, guy. Morons like yourself make great hypocrites. The fed reimburses states thru the highway trust fund for certain projects, not specific jobs. The fed does not dictate what the state should build or when with their share of the trust finds; the state does. There was more money to fix that bridge in the state budget than China has Chins. You're just an idiot. That's a fact, and an apologist for a fraud.

Posted by AnonyMousey | August 8, 2007 1:50 PM

Don't put rail on the new bridge. Run some Personal Rapid Transit lines across it. Hanging compact-car-sized vehicles over University Avenue parking lanes won't wreck the street like their antiquated toy train will.

Posted by burt | August 8, 2007 7:34 PM

Something is rotten in the kingdom of MnDOT.

A letter of condolence from the Hungarian embassy.
http://www.huembwas.org/

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