Falling Down

Chuck Hoffman was just seconds from plunging into the water.

The 60-year-old computer specialist from New Brighton had driven his green Subaru Forester over the bridge to solid ground as the 400-foot stretch of motorway collapsed behind him—splashing down some 10 stories into the Mississippi.

"I was going southbound at six o'clock, and I felt my car going up and down. Traffic was about 20 miles per hour. It was strange, like being on a diving board or something, and I thought 'What is going on?' I had no idea.

"And I glance in my rear view mirror, and I saw the bridge collapse right behind me. It just disappeared.

"I didn't know if more bridge was going to collapse, so I look forward, and I saw the bridge ahead of me undulating up and down, and I thought, 'This could collapse too.'

"I saw people going down—it was kind of over the brink from where I was. You could see cars on the other side going down.

"I was right on the edge when it all went down." —G.R. Anderson Jr.


President Bush didn't bother waiting until all the bodies had been recovered from the Mississippi river to politicize the disastrous collapse of the I-35W bridge at a morning press conference the day after the tragedy.

After briefly mentioning that Minneapolis was in his prayers and mispronouncing Governor Tim Pawlenty's name, Bush quickly segued into what appeared to be a previously planned speech haranguing Congressional Democrats for not sending him spending bills to sign, including an annual transportation appropriations bill.

Although Bush said the federal government "must respond robustly" to the bridge collapse, he used the majority of his airtime to argue against increasing federal spending, which could provide the money to shore up our crumbling transportation infrastructure.

"Massive tax hikes are the last thing the American people need," Bush said.

It was perhaps the president's most embarrassingly ill-timed performance since he strummed a guitar while New Orleans drowned. —Kevin Hoffman


One of the more frightening pieces of information to emerge shortly after the disaster is that many of the state's bridges are in even worse shape than the one that collapsed.

The Minnesota Department of Transportation ranks bridges on a 100-point scale in terms of structural adequacy. According to an April 2005 report by the agency's Bridge Management Unit, 72 bridges in the seven-county metro area scored 50 or lower, marking them structurally deficient.

The I-35W bridge that collapsed scored an even 50. In other words, there are 71 other bridges in the metro area that were considered more likely to falter. —Paul Demko


Elwyn Tinklenberg, who served as the state's transportation commissioner under Jesse Ventura, says the I-35W bridge collapse is emblematic of an eroding, underfunded transportation system.

He points to a recent MNDOT assessment, which concludes that the state is underfunding transportation maintenance by a billion dollars a year.

"That is not sustainable," Tinklenberg says. "We can't afford to do that and expect our system to continue to perform safely."

So, what to do? Tinklenberg calls for a gasoline tax hike. The last time the state raised the gas tax—which stands at 20 cents a gallon and is a key component of the state's transportation budget—was in 1988. In May, Governor Pawlenty vetoed a five-cent gas tax increase, saying such a hike would be "untimely and misguided." —Jonathan Kaminsky


Investigators looking into what caused the collapse will have an invaluable tool at their disposal: a computer model of the I-35W bridge that an employee of the Federal Highway Administration designed while pursuing a Ph.D. at the University of Minnesota.

National Transportation Safety Board chairman Mark Rosenker declined to provide the name of the FHA employee responsible for creating the computer model, but estimated that the program's existence will save investigators months of work.

"We'll take apart every one of the elements (in the model bridge) that creates the picture we now know," Rosenker said. "This will speed up our understanding of which one of the components failed." —Matt Snyders


So exactly how do you inspect a bridge that hangs 60 feet above a river?

Bridge inspections, it turns out, are a decidedly low-tech procedure, according to transportation department officials in Wisconsin and North Dakota. Essentially, they're a more complicated version of a pilot's walk-around of a plane before takeoff. Inspections are primarily visual: a crew visits the site and inspects the structure for obvious flaws—corrosion, cracks in the steel or concrete, or peeling paint that could lead to corrosion.

The crews are small. For a bridge the size of I-35W, a crew of two to four would be typical, and they could be on the job for several days.


Before beginning, inspectors familiarize themselves with the bridge and past inspection reports, which could include photos and even hand-drawn sketches of problem areas.

Many parts of the bridge can be inspected from some distance away. The most important parts of the bridge—including "fracture critical" components at stress points, whose failure could spell trouble for the bridge—are viewed more closely, ideally from an arm's length away.

Inspectors, for example, will close lanes and walk the roadway looking for potholes. They will examine the steel beams supporting the deck for cracks and corrosion. They look at the concrete abutments holding it all up for cracks or settling. They check that bearings the bridge rests on are aligned correctly and painted.

For hard-to-reach places, crews employ a "snooper truck," equipped with a long arm and bucket that swings a crew member over the side for an up-close inspection.

If they find something wrong, they can bring in diagnostic equipment such as ultrasound to get a better look at the problem.

Small cracks in steel can be easily repaired by, paradoxically, drilling small holes at either end of the fracture, which stops the crack from spreading. But repair crews have to be careful to drill at the end of the crack, which often can't be seen by the naked eye. To find it, they can use a dye penetrant test, in which they coat the surface with a red dye, wipe it off, and cover it again with white dye. The red coloring will seep through the white dye along the crack and reveal itself.

Bridge workers can also outline a crack by the magnetic particle method. They use magnets to create a magnetic field in the steel beam, then sprinkle the area with a powder of iron filings, which will outline any cracks present.

Bridge inspections are conducted at least every two years (the I-35W bridge was looked at annually). Special fracture-critical inspections were conducted every four years, but the federal government recently recommended two-year intervals.

When the inspection is over, crews rate the deck, superstructure, and supports on a scale of 0 to 9, with 9 being the safest. The I-35W bridge's superstructure was rated 4, meaning inspectors found it in poor condition. —Matt Smith


Will the I-35W bridge collapse have serious environmental ramifications? The massive heap of concrete, steel, vehicles, and lord knows what else would seem to pose a danger to the well being of the Mississippi River.

Environmental concerns initially focused on three railroad cars that were crushed by the collapsed bridge. There could have been serious ecological harm if those cars had been carrying a highly toxic substance, such as benzine. But as it turned out one of the cars contained plastic pellets, while another held plastic powder. The third was empty.

"There was a little bit of spillage," says Sam Brungardt, public information officer for the Minnesota Pollution Control Agency. "Nothing that would pose an environmental or a health threat."

Another possible environmental issue stems from gasoline seeping into the water from crushed vehicles. But oil pollution appears to have been surprisingly limited. "There was a little bit of oil but that dissipated very rapidly," says Brungardt. "We never really found pockets of oil."

A concern going forward will be air quality. As workers untangle and remove the debris, the MPCA is worried about what types of particulate matter will begin circulating in the air. The agency has done preliminary testing near the site of the bridge collapse to establish baseline levels of lead, asbestos, silicates, and other potentially dangerous materials. "Those are all things that are known to affect health if they are breathed in," Brungardt says.

But overall it doesn't appear that the bridge collapse will have any serious, long-term impact on the health of the Mississippi River. "One could imagine scenarios where much worse cargo could have been on that bridge," says Whitney Clark, executive director of Friends of the Mississippi river. "That does not appear to have happened."—Paul Demko


The Star Tribune and Pioneer Press newsrooms recently received an unexpected box of junk food, courtesy of The Roanoke Times. The spoils include spicy pork rinds, moon pies, Virginia peanuts, Hostess cupcakes, and Dove bars. "There's also one very out-of-place looking can of lima beans," Pi Press metro reporter Frederick Melo reports via email.

This sweet tradition was apparently started by The Oklahoman newspaper, which learned the stresses of covering a major breaking news story after the Oklahoma City bombing of 1995. Last April, after Seng Hui-Cho killed 32 people at Virginia Tech, the Roanoke Times received a large box of artery clogging edibles from their counterparts in Oklahoma. "It was just like a big hug," recalls Carole Tarrant, editor of the Roanoke daily.


The loot is apparently equally appreciated by newsroom staffers in the Twin Cities, many of whom have been logging long hours since the I-35W bridge collapsed last Wednesday evening. "I'm in fat boy heaven," reports Melo.

Tarrant says she only asks that the Pi Press and Strib reporters reciprocate the gesture down the road. "Tell 'em to pass it on," says Tarrant. "That's my only request." —Paul Demko


The collapse of the I-35W bridge has suddenly shoved the relatively obscure science of bridge engineering and inspecting into the spotlight. Here's what you need to know:

What does "structurally deficient" mean? It's a federal designation based on annual or biannual inspections. The feds use a nine-point scale to rank the structural soundness of bridges in three different areas—the deck (which is what you drive on), the superstructure, and the substructure. If a bridge ranks four or lower in any of these areas, it makes the list.

Are such bridges safe to drive on? So they say. "We view that term as a programmatic classification rather than an indication of level of safety," says Tom Everett, of the National Bridge Inspection Program. "It is not a classification that indicates a bridge is dangerous, nor that that bridge must be replaced."

How many bridges in Minnesota have been labeled "structurally deficient?" According to MNDOT, there are currently 1,160 in the state that carry this designation. That's roughly 8 percent.

How does this compare to other states? Nationwide, 13 percent of the country's bridges, or approximately 75,000, are labeled "structurally deficient."

How long had the I-35W bridge been deemed "structurally deficient?" Since 1990.

Why was it deemed "structurally deficient?" The I-35W bridge initially earned that designation because some of its bearings were corroded, according to Dan Gorgan, MNDOT's bridge engineer. Subsequent inspections revealed additional corrosion in its joints. Finally, there were "fatigue cracks" on the approach spans of the bridge.

How often was the bridge inspected? It's been inspected annually since 1993. Prior to that it was inspected every two years. "During recent inspections in 2005 and 2006, we found no evidence of additional cracking in the bridge or growth in the preexisting cracks," says Gorgan. The 2007 inspection had been interrupted by construction on the bridge and was to be completed in the fall. In addition, the University of Minnesota's Department of Civil Engineering conducted a study of the bridge's fitness in 2001. The conclusion? It did not need to be replaced in the near future.

Who built this thing? Industrial Construction, a company that is no longer in business. Construction began in 1964 and the bridge was opened to traffic in 1967.

How many cars drove over this bridge? Approximately 141,000 daily. That makes it the third busiest bridge in the state, next to I-94 (157,000) and I-694 (150,000).

What kind of bridge was it? It was a steel arch truss bridge. "It's an underdeck truss, meaning it's supported from below," says Gorgan. "There were two arches that supported this bridge."

Are there any other bridges of this kind in the state? Yes, five others: Inspections on three of them were completed last week and no problems were found. The remaining two are slated to be examined ASAP.

When will the bridge be rebuilt? Nobody knows for sure yet. The city and state have put together a team to study the issue, according to MNDOT engineer Khani Sahebjan. But any rebuilding will obviously have to be put on hold until the collapse of the bridge has been thoroughly investigated, says Sahebjan. "When we get permission to remove the structure, that's when we can start construction." MNDOT hopes the bridge will be rebuilt by the end of 2008. —Paul Demko


John Weeks is what some people might call an obsessive. Over the past two years, he has spent weeks at a time traveling alongside the Mississippi River, photographing more than 300 of the bridges that span that mighty body of water, from Itasca to New Orleans.

His downtime between trips is largely devoted to cataloging information on each bridge, such as its age, construction material, daily traffic count, river elevation, and other factoids that, until last week, might have seemed somewhat superfluous to anyone but himself.

So Weeks is perhaps uniquely equipped to tackle some of the conspiracies that cropped up about the I-35W bridge collapse. And that is what he has done over at his website, Among the more entertaining new urban myths that Weeks has debunked:

  • Numerology predicted this event. If you count the "I" in I-35 as a 1, then 1 + 3 + 5 = 9. Also, the date of the collapse was 8/1/2007. 8+1 = 9 and 2+0+0+7 = 9. Since nines are coming up over and over, the bridge must have been doomed. But there's nothing about the number "9" that would indicate a bridge collapse, Weeks writes. "Just adding digits to find 9 or any other number is contrived."


  • President Bush wants to fast-track the new bridge to be part of the NAFTA highway. Nice try, but Weeks points out: "The so-called NAFTA highway, which would run from Mexico to Canada, is I-69....The I-35 bridge is not critical for the movement of goods on a national scale."

  • Police are covering up the fact that large numbers of Somalis perished in the collapse. Perhaps this is a reaction to the unbelievable good fortune that more people weren't killed, but even a moment of thought is enough to debunk it. "Keeping it quiet would require preventing a large number of people from talking," Weeks writes. "This theory just doesn't make sense."

  • The collapse was caused by the alignment of the planets, which was the same as on the day in 1967 when the Silver Bridge collapsed in Ohio. An intriguing theory, except that it simply isn't true. "The planets were not in the same positions," Weeks writes. Besides, "planets simply cannot put enough force on anything to affect it here on Earth."

  • Russians report that they have evidence that this was caused by a secret U.S. military sound weapon being tested at the nearby secret Rand Corporation physics lab. The answer to this one holds true for all the cockamamie theories you'll hear peddled by wild-eyed nuts over the next few months: "How is it that the conspiracy people got it but the reputable newspapers did not?" —Jonathan Kaminsky

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