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One entire span of the Minneapolis 35W freeway bridge has collapsed into the Mississippi. WCCO-TV is carrying live streaming video.
We have so many friends and readers in Minneapolis/St. Paul. Could you please let the rest of us know how you are? Minn-StF has a check-in site.
More: Elise Matthesen says that cellphone service in the Twin Cities appears to be scrod—not surprisingly, since the bridge carried a lot of telecommunications infrastructure, and everyone’s simultaneously trying to phone their friends and relatives there. She suggests you send e-mail instead.
This is the sort of thing that the Incident Command System (ICS) was designed to handle.
No surprise that cell phones are clobbered. When you're making your emergency plans, make comm plans that don't rely on cell phones.
And, consider setting up rally points -- places where you and your party will re-gather if the world falls apart, you get separated, and comms are down hard.
The newscasters are blathering about heavier-than-usual traffic, resurfacing repairs, and a reported jackhammer as possible reasons for the bridge's collapse. None of those sound to me like they're anywhere near the right magnitude.
Whoever's in command of the situation is smarter than Rudi Giuliani -- they're keeping responders out of areas that could get hit by a secondary collapse.
We took notes on what happened, I think. Because yeah, preserving responders and all that, it's kind of key.
Heavier than usual traffic?
Teresa at #2: I agree with you about magnitude. Maybe I just don't understand anything about what makes a bridge collapse, but I'm looking at the pictures of the bridge on CNN, and if "heavier than usual traffic" does THAT, I'm not driving anywhere, any more, EVER, until someone tells me all about the unique structural defects of that bridge. Because, um, oh. my. God.
In the view CNN keeps showing, there's a lonely white car that looks like it was one moment from plunging in over the edge of the collapse. How on earth did that driver keep the car from going over? There's an Explorer a bit further back that seems to have had the right idea and turned the car sideways to keep from sliding in. And it's all godawful. But that white car...we keep coming back to it. If I'm the white car owner, and I'm okay, well then I just got religion, writ large.
OK, for those of you watching news coverage, here's what they aren't giving yet on MSNBC, because as they said they don't have a Minnesotan handy:
They are showing footage of the collapsed 35W freeway bridge, and right next to it is another bridge with arched supports. That bridge is the 10th Avenue bridge.
I hate to contradict a Minneapolitan, but according to Google Maps, while that other bridge connects to 10th Avenue on the east side, it's in fact called the Cedar Avenue Bridge.
punkrockhockeymom: They were reportedly doing construction on/near the bridge when it went down.
MSNBC just said "cellphones are inoperable at this time -- can't explain that in the slightest." Well, the 35W bridge carried a LOT of fiber, a lot of telecommunications infrastructure. Dunno if that is why, but might factor in.
The "nearby pedestrian bridge just out of frame" that MSNBC referred to might be the pedestrian bridge that they made out of the old railroad bridge James J. Hill built across the Mississippi. (For those of you who have played the computer game Railroad Tycoon, that railroad bridge is the bridge that Jo Walton exclaimed over when she saw it for real, because it's the image of what you get in the game when you upgrade to stone bridges.)
Good GRIEF. I've never seen anything like this.
I don't see how the injury count can be low, but I hope it is.
The ASCE puts out an annual report on the nation's infrastructure. The 2006 report reads as follows under the Bridges section:
Between 2000 and 2003, the percentage of the nation's 590,750 bridges rated structurally deficient or functionally obsolete decreased slightly from 28.5% to 27.1%. However, it will cost $9.4 billion a year for 20 years to eliminate all bridge deficiencies. Long-term underinvestment is compounded by the lack of a Federal transportation program.
So I suppose this shouldn't come as a huge surprise.
Yeah, you're factually correct.
http://en.wikipedia.org/wiki/Cedar_Avenue_Bridge_(Minneapolis)
"The Cedar Avenue Bridge crosses the Mississippi River near downtown Minneapolis, Minnesota and also in proximity to the University of Minnesota. An established street name is Tenth Avenue Bridge since the north end of the span meets 10th Avenue Southeast. "
I'm showing my age, and my U of M vintage, I guess.
A note to underscore what Jim is always telling us, this report was on WCCO's website:
"I thought it was just construction going on ... it was a free fall all the way to the ground," said one person who was on the bridge at the time. "Thank God I was wearing my seat belt. The only thing I was hit was the steering wheel."
See? WEAR YOUR SEAT BELTS. It helps in more situations than you might imagine.
Jayminy Crismuss, they already have the Wikipedia article on Interstate 35W updated with news of the collapse.
Glad to see people checking in. It looks pretty horrendous.
I, too, will be very surprise if there are indeed only three fatalities. That's a lot of cars falling a long, long distance.
It sounds pretty horrible. The pic on CNN.com makes it look as if the bridge was sliced by a gigantic knife.
I rarely decloak on ML, but Oleander and are fine. I was on that bridge coming home from work about 4.5 hours before it collapsed. I've been telling him for 6 weeks that I've been scared to drive on it with all of the jackhammers taking off the bridge deck, and now this. I can't think, all I can do is sob and wait on word from our friends and family...
Patrick, I think you may have just done the equivalent of telling someone "No, that's not the 59th Street Bridge, it's the Queensboro Bridge."
Also, while researching this comment, I discovered that there's something called the National Bridge Inventory that assigns unique ID numbers to bridges.
How awful. My thoughts are with the people there.
If it had been a suspension bridge, I could see how one support strut going could bring down the whole span. But it looks like a trestle bridge, and I don't know if the same dynamics apply.
What was the weather like the last couple of years? If the temperature changes were very drastic, with a lot of moisture, that possibly could have weakened the structure with many thin, deep cracks not readily apparent to inspectors.
Melody at #16:
My heart goes out and my prayers are with you and your loved ones. I'm glad you're safe. I hope everyone else is.
I usually make a policy of lurking heavily, but wanted to say thanks for the post. I work at the U of M, drive over the 10th ave bridge every day and saw that bridge chock full about an hour before it collapsed. I'm trying to account for everyone without being able to use a cell phone, and while I don't think anyone from my Real Life posts here it really helps to know that I'm not actually isolated, even though I feel it.
Sorry for babbling. And thanks.
CaseyL, you may be more correct than you know. About an hour ago, our Channel 5 news had a bridge expert on air, when they received a report from 2006 that there were cracks reported in the supports. He backpedaled and generalized his response after his first WTF reaction, but it was evident on air that it shocked him to some degree.
Summers here are almost always steamy, and it has seemed particularly hot the last few years, but that could be just my imagination.
...and many thanks to you all from myself and Ed (Oleander) for your thoughts and good wishes, they mean a great deal.
Though the odds of them being in that part of the Twin Cities at rush hour was slim, calling my parents and getting the "all lines busy" message from cel and land lines for ten minutes was still a pretty horrifying experience.
Luckily, I've been able to get in touch with my sister and other friends in the area (including one who works less than a mile away) via email, IM, and forums.
So I fully support what Jim said in the first response: in a time of crisis, be prepared to use alternate communications channels. And I'm going to take to heart what he said about planning those channels before the disaster occurs rather than waiting until it does and scrambling. It might just be what convinces my mom to treat email more seriously.
Unique ID numbers, good idea.
Jim, they did an interview with the ICS guy who was recently training the local DOT guys, but they just kept asking him about the bridge -- didn't understand what he was about.
Elise, Karen says she heard about it from your mother, and they all say thank you very much for getting word to them.
Avram, #17: "Patrick, I think you may have just done the equivalent of telling someone 'No, that's not the 59th Street Bridge, it's the Queensboro Bridge.'"
That exact thought had just occurred to me.
Has anyone had any luck dialing land lines in the 612 area code? Some folks I know are trying to get in touch with a friend there to verify she's okay, but we're getting nothing but fast busy.
For those of you who have friends or family in this area, the Red Cross is setting up a web site (don't have the URL yet). check redcross.org
HCMC patient info hotline...612.873.3400
Cell phones are still mainly out; I couldn't reach my boss at the Red Cross chapter where their doing triage and feeding the rescuers...
I got through to my family (651 area code), and they're ok. Haven't tried anyone in 612 though. Supposedly there's a baseball game tonight, so lots of people may be downtown for that.
Has anyone had any luck dialing land lines in the 612 area code? Some folks I know are trying to get in touch with a friend there to verify she's okay, but we're getting nothing but fast busy.
Best I managed was a single ring from a 612 number, after which it dropped immediately to a busy message rather than voice mail.
Anticorium, the cellphone service here is hosed, and probably landline service is hosed too, due to lots of fiber being carried by the bridge. Telephone calls crossed that bridge all the time, and nobody thinks about them....
My suggestion: if they can possibly try e-mailing, that'll work a lot better.
Ah! Some local cellphone service working now.
Tristan, there is a baseball game going on. They didn't cancel it because that would just dump a lot more traffic into an already difficult situation.
Anticorium #26 .... We're having some luck with 612 from local landline here... send me the info and we'll try for you... RNcalledEd@comcast.net
Oleander, that's the same thing I was doing on 9/11 -- people could get through to me long distance via chat, and I could get through to their friends and relatives on local land lines.
The video I saw (from the Fox News(!) affiliate -- both the CBS and ABC affiliates have much less useful coverage) made it clear that both north and south piers are still standing, so whatever happened to the bridge happened in the span, not in the supports.
My family is all okay; my aunt had crossed the bridge only a minute before it collapsed, but is uninjured. Not that you know any of them :-)
I'm in shock. I grew up in Minneapolis. I have friends who went to the U of M. I've driven over that stretch of highway. My thoughts are with everyone who's still waiting to hear.
I suppose we'll have an explanation for this eventually, but right now it just seems so random. I think I need to stop looking at the pictures.
See also: Making Light--Tips for an apocalypse
#1 Jim, #24 Teresa--I think I heard the same guy on MSNBC that Teresa mentioned--he finally got what he had been doing with the local emergency responders across, and was able to explain that they looked to him to be doing what they were supposed to--he mentioned staying back in the safe area, and setting up a system that avoided political issues, among other things, such as getting good communications going among the responders, IIRC.
I have to cross the Cumberland River twice a day, going to and from work, as does my landlord--we are looking at the tube and feeling our skins crawl from head to toe.
When I visit my mother and brother in Kansas City, I cross the Ohio and the Mississippi twice, and the Missouri four times, in a round trip. On my next trip, I imagine I'll be even more skittish about them than usual.
Bridges need constant, active maintenance, and too many don't get it. Corrosion is a big enemy, and can work on structure unseen and unsuspected--and please take that as a general observation bridges in general, and not a wild-assed guess about the cause of this horrible event.
Our best wishes to everyone in the Twin Cities area, and strength and courage to the emergency workers on the scene.
And while we're on the subject of the news from Minneapolis, Steve Brust is now a grandfather.
The reports I've been seeing say that the bridge was a single-span steel bridge. If true, collapse in the middle would be enough to bring the whole thing down.
Teresa, I posted that in the Open Thread yesterday. I meant to post it sooner, but forgot.
Oh. My. God.
My thoughts go out to all of you in the Twin Cities area. Hoping all is well.
And for those in the PDX area...um, you might want to have cautious thoughts about the Sellwood Bridge. I have nightmares about that one, and they're saying it should have been repaired or replaced 30 years ago.
Minneapolis mayor reported 6 confirmed deaths at a press conference about 45 minutes ago, but that recovery was still ongoing in the river. There are at least 2 dozen injuries. There have been many survivors, even people who dropped the full height in their cars, as well as a school bus full of children.
The bridge was built so that there are no pylons (spelling on that might be botched) in the center of the river - the span is supported entirely by the supports on the two banks. The construction on the bridge was resurfacing and apparently involved lots of jackhammering for several days. No one knows if that contributed or not. One of the construction crew workers is still unaccounted for.
A friend was on the river on the Mississippi Queen for his company annual party when the bridge collapsed, about 15 minutes from going under it. At last report nearly an hour and a half ago, they were heading back upriver to de-board at some as-yet-unknown port.
(And I think that occasionally should be added to your spelling reference. I can never remember how to spell that one!)
punkrockhockeymom @ 5: Heavier than usual traffic does not do that, at least not by itself. It may possibly be that if the bridge is already essentially broken for some other reason, the traffic is enough to be the final straw, but that's about all it is.
My impression of the usual safety factors on bridges is that they're very well beyond sufficient to make it safe to pack cars on top of them as tightly as they will physically go.
CaseyL @ 18: The same dynamics apply to truss bridges as suspension bridges, though not necessarily as strongly. It's still a matter of the fact that having one support go will cause all of the corresponding supports to suddenly carry a lot more load, a that may be enough to break them too, at which point you've got a chain reaction gone critical.
I've also seen cases in engineering textbooks where some undetected cracking was happening in the supports, so that when one of them failed, the others were already weakened by corresponding cracks, and definitely couldn't handle the sudden extra load.
The newscasters are blathering about heavier-than-usual traffic, resurfacing repairs, and a reported jackhammer as possible reasons for the bridge's collapse. None of those sound to me like they're anywhere near the right magnitude.
Every once in a great while, a barge going down the Miss will hit a bridge and take it out.
Exxon Valdez, but with a boatload of corn.
I would not be surprised, however, if it was something small. Stress cracks. Rusted cable. Galloping-whatever that bridge taken out by wind that hit resonant frequency. Or maybe someone cut a bolt to replace a beam, but didn't realize that the guy who was supposed to put in the support jig beforehand didn't get around to it.
We are at NASFIC and someone (I think coming from the Minneapolis direction) told us about it when we were on our way out to dinner. What we were intitally told is that it was a construction error.
Siince we came back, we've been watching CNN for a little while and there's not a whole lot of info. (Anderson Cooper seems to be trying really hard to get someone to tell him why, but it ain't happening.)
Oleander@33: Thanks for the offer, but it turns out the number I have is outdated. I got through but was rewarded by a message telling me the number is changed, but not to what.
My local news is saying the mayor said 7 dead.
The Mianus River Bridge, carrying I95 in Connecticut, collapsed in 1983 from the failure of just two pin and hanger assemblies.
@9: "Good GRIEF. I've never seen anything like this."
I have. And that was at rush hour, too. Fortunately, the World Series between Oakland and SF, was to start minutes later, and a huge fraction of folks the Bay Area were perched in front of their TVs instead of clogging I880 as they normally would.
Like everyone else here, my thoughts are with thefine folk of the Twin Cities. Hope as many of you and yours are as safe as possible.
What I think, in the end, is that this will be seen as symptomatic of the same problems that lead to the destruction of New Orleans: inadequate attention to national infrastructure. However, the key phrase I just heard from MSNBC was "work on the joints," which is to say that they were doing repair work on the joints of the bridge. 2 of the 4 lanes were closed because of construction.
I have a fascination with the collapse of the Tacoma Narrows Bridge. Resonance patterns were important in that bridge collapse. I am very curious about what might be meant by work on the joints, because that can take us into Tacoma Narrows territory.
Wow. I'm looking at that as a former bridge structural engineer (small e, not a PE). Wow.
There are a lot of secondary failures there, mainly spans being pulled off of their expansion joint pads. That's the sort of thing that they've spent the last 30 years fixing in earthquake zones after the Loma Preita quake.
I can see two possible main failures:
A stability failure over the abutment could lead to the bridge collapsing down and sideways. This would probably be related to heat or corrosion, but there would need to be some other trigger. An unbalanced load, or something.
It's also possible that it was a tension failure over the other abutment, but that's been discounted a bit by the engineer in one of the clips. This one could be related to the construction or corrosion or cracks.
And, I note, there are a few bridges that look a little like that one in Seattle...
Key phrase from Fox News "more of a metal fatigue failure than a concrete fatigue failure."
This is why I am keeping my landline. I haven't been able to check on friends with cell only, but someone who was supposed to stop and couldn't by got through a little while ago, no problem - landline to landline.
If you want to check on MnStf and other locals, there is a check-in post on Live Journal:
http://community.livejournal.com/mnstf/94019.html
Whoops, didn't notice that the check-in was part of the main topic. I'm a bit fried.
And it hit 92 degrees today, and is still in the upper 80's. May have been a contributing factor.
Actually, on closer examination, turns out those bridge ID numbers are only unique within a state. Given that, you'd think they'd stick a state identifier on 'em, but it doesn't look like they do.
Teresa and I saw the same thing that "George Smiley" (hey, tell Karla hello!) links to in #50 -- just a few days after the event. Along with the World Trade Center site a few days after 9/11, it's one of the truly weirdest and most upsetting things I've ever seen.
I read Linkmeister @ 10 and my first thought was 'a month's worth of Iraq could have paid for that.' (Probably wrong, but it would surely have paid for a year's worth of repairs.)
I second George Smiley's comment on the Bay Bridge. There's a picture in my memory of a vehicle perched on the edge of the place where the section dropped. Also memories of similar pictures from other quakes in other locations, where the structures failed and the brakes didn't.
One reason I have a roll of quarters and a pre-paid phone card in my Urban Survival Bag is because in the event of a major catastrophe cell-phone service won't be reliable.
While it's possible that a lot of cable was taken out with the bridge, another factor in the phone problems is the everyone calling everyone else problem - the exchanges are overloaded. I saw this with Mt. St. Helens, and I've seen it several times since as a result of being responsible for business telecommunications for a business on the same exchange as a major ticket company.
Eric @ 52 - er, which Seattle bridge? Galloping Gertie was a Tacoma bridge. Mind you, it's not like ours don't fall down.
For those interested in this stuff, Shaun Kelly has been posting his observations from listening in on the radio chatter in his LJ: kalikanzeros.livejournal.com
And Nancy McClure posted a good picture to give you a better idea of where the bridge is located:
http://www.hand2mouse.com/mcclure/bridgecollapse.jpg
Re: #58
If we paid for bridge repair at the rate we're paying for Iraq, we'd get 'em all done in a bit under seven years.
As I keep saying: Who need bin Laden when you have Murphy?
One of the locals interviewed on NPR said something interesting:
The fallen deck floated for a time, allowing passengers in the car to get out.
I've avoided TV coverage up to now. I might just turn on CNN for a bit so I can visualize what happened.
* * *
Discussion about cell phone outages makes me think:
Man, I wish we had a competent Federal government. Incidents like this should lead to Lessons Learned conferences and fixes to our communication infrastructure.
With Bush, we'll get some trite expressions of sympathy and some bluster about building the bridge bigger and better.
Update:
7 confirmed dead, one construction worker missing. As of 2230, there were 60 people taken to local hospitals, with at least 6 critical, but likely more.
No attempts have yet been made to get under the main sections, especially under water. Rescue workers will try searching the river tonight, but this is difficult due to currents and darkness. Just now the operation went from "rescue" to "recovery" mode.
The bridge passed muster in 2006, but there were notes made regarding cracks in the crossbeams that support the girders running with the road bed. That note clearly alarmed a safety engineer KARE interviewed, but he admitted that he is not familiar with this bridge.
The main bridge was a single span arch bridge built in 1967. It was considered unique at the time for the size of the open central span (about 550 ft long and 65 ft above the water at the apex). Overall the bridge was about 1000 ft long and the entire thing went apparently within just a few seconds.
No clear word on where the collapse started. One woman saw light poles swaying and stopped in time. A school bus with 50-60 kids was on the bridge but were all rescued by others involved in the collapse (Some of whom had just fallen 50 feet...now THERE is real balls!). 12 kids were taken to the hospital and 2 were serious. See the City of Minneapolis website for a hotline for out-of-towners. Also see www.redcrosstc.org for info or to donate to the Red Cross.
The Red Cross can be reached all night at 612.871.7676 for those seeking loved ones.
Estimates vary, but between 50 and 100 vehicles may have been on the bridge. No idea on how many are under water or under the larger sections.
The phones are in better shape now, both cell and landlines...
MY THANKS to everyone for their words of comfort. Melody, who works just a couple blocks from the bridge, drove over it just a few hours before the collapse, and several of her co-workers also use the bridge during rush hour. She was quite upset, and also sends her thanks to everyone.
Credit where credit is deserved:
Target Stores just delivered an entire 18-wheeler full of water and food supplies to our Red Cross chapter for the EMS and investigative workers.
Apparently there's some locals liveblogging over on Firedoglake and DailyKos as well.
Margaret Organ-Kean @60 I think eric was referring to the I-5 bridge over the Lake Washington Ship Canal, which is of a similar vintage and even higher than the 35 bridge, or possibly the long viaduct over the southern end of the Duwamish Valley. Or the Albro bridge, perhaps. Seattle is full of bridges in bad repair, with known problems. The Ship Canal bridge is undergoing repairs right now, as is the much older )and more like the Embarcadero Fwy) Alaska Way Viaduct.
Going cheap on road taxes (thanks, Tim Eyman, you asshole) is an invitation to disaster. Today, disaster took up the invitation. (And I'm freaking out about my cousins and Uncle in the twin cities).
Seattle had Galloping Gertie, the Tacoma Narrows bridge, back in the 40's. It had just opened, too. Also, a few years ago the brand-new I-90 concrete pontoon bridge sank when the access doors to the pontoons were left open and lakewater flooded in (years of lawsuits over that one; but no injuries, because it sank slowly enough to clear everyone off).
The current Big Bridge Issue here is the Alaska Way Viaduct, a huge elevated highway that runs along the waterfront. It's a vital part of the transportation system, and was badly cracked in the February 2001 earthquake. It's been repaired and retrofitted, but the feeling is that it needs to be replaced. The city is divided over whether to build another elevated viaduct, or dig a huge tunnel and run the highway through that, or build a surface highway. (Whatever they do, while it's being done, the commute - already a nightmare here - will resemble one of the Outer Circlesof Hell.)
This being Seattle, where we study and discuss things to death and our city officials are chronically unable to make decisions, I had doubted anything would actually be done until the damn thing up and collapsed. But the 35W disaster will likely concentrate a few minds here.
Just checking in. I was about two exits south at the time, headed further south and away while entirely oblivious.
Seattle =/= Tacoma, please. I'm traumatized already by sitting on the bus in Olympia and hearing people say "here in Seattle."
Seattle has plenty of problematic bridges (I didn't mention the Lacey V. Murrow /520 floating bridge, even) and doesn't need, really, to appropriate the ones belonging to entirely different counties.
(Sorry, but I socialize with WS-DOT bridge inspectors, and it takes me strangely some times.)
Oh, I've seen plenty of disasters, but usually there is an earthquake, a flood, a fire, a collision with a plane, or SOMETHING. The Tacoma Narrows had resonance (so did the pedestrian bridge in front of the Tate Modern, aka The Wobbly Bridge, but they fixed it.)
This... is like a piece of the sky falling down.
The Vajont Dam disaster was worse, but I wasn't born yet at the time.
Edward Oleander: "A school bus with 50-60 kids was on the bridge but were all rescued by others involved in the collapse (Some of whom had just fallen 50 feet...now THERE is real balls!)."
Indeed so. I love my town. As the WCCO website says:
"New at 10:34 p.m.:
One young man helped all of the children out of the back door of the bus that contained 60 children. Instead of rushing to safety many other people ran to the bus to help the children. All of those kids are safe."
Because that's what ya do. Having just fallen 50 feet or not.
There's an interesting article in one of the local papers about witnesses who became rescuers. For those (like me) who like reading the EMS Geekery posts here, it's fascinating reading.
One thing I've not seen mentioned anywhere yet is how deep the river is, how wide, how fast the currents, etc. Does anyone know?
Joyce @ 42 -- I thought the same thing about the Sellwood Bridge.
It looks like The Oregonian had the same thought:
http://www.oregonlive.com/news/oregonian/index.ssf?/base/news/1186026912213310.xml&coll=7
#74 -- The river is about 300-400 feet wide there, and for the most part less than 10 feet deep. There is significant silting, so a dredged channel is maintained. There is a lock and dam just upstream, so the current is fairly swift and visibility poor. Considering the debris involved, diving will be very hazardous, even in daylight...
Margaret Organ-Kean @60 -- I was referring to the Fremont bridge and the I5/ship canal bridge, both old trusses. There's also Deception pass as well, but that's hardly Seattle.
Re Concrete vs steel failures: Concrete really doesn't fatigue in the same way that steel does, since steel fatigue is a tension failure, and tension failures in concrete are quick and dramatic. That's why concrete is never designed in tension. Fatigue failures in steel are very slow until the crack reaches a critical length, and then suddenly very fast.
It's unlikely that the bridge deck caused this failure, since anything that would fail with the deck would tend to be pretty locally redundant and not supporting a whole lot. It could have contributed to it by allowing access to tension members, but that's a different issue.
I'd put my money on either a tension member going in fatigue or a buckling failure as the whole truss flopped over. Or both, in either order.
JESR and Casey at #67, #68, #70
I live in West Seattle - the Alaskan Way viaduct is a major big deal to me! When the Nimitz went, the first thing I heard on the radio made me think it was ours.
The Alaskan Way viaduct is a real mess - it's built on fill and there's the earthquake damage. On the othe hand, an engineer I know has talked to some of the engineers inspecting the viaduct and he thinks they've been pressured to turn in reports that things are worse than they are. Take that for what it's worth - second hand gossip. If you want a motive - well, whether the viaduct is OK or not, the sea wall in that area is definitely not, and if the city builds the tunnel, they could use part of the federal/state funds to rebuild the seawall.
If the seawall goes, I don't give a hoot for the chances of the viaduct or the buildings down by it. They're all on fill, and the one I worked in for five years (a new building, too) used to rattle like there was an earthquake going on every time a freight train went through.
Don't even get me started on the commute - the day after the 2001 earthquake it took us 2 hours to get out of West Seattle, because the viaduct was closed.
I was just curious as to which one Eric was thinking about, since I have several personal disaster candidates - including the South Park bridge, the 520 (getting hit by a barge cannot have helped it), and the Fremont bridge (not that it will fall down so much as that it will get stuck some fine day).
And, what I forgot in my earlier post - good thoughts to the Twin Cities and those with relatives and friends there.
Here's a blog post from a Minneapolis blogger who lives across the street from the bridge. His photos have been posted to Flickr.
There's not much I can say or do just now to help in this situation, except that I hope for the best for all who were on that bridge, and for all who had friends and loved ones there. I can say, FWIW, I've been very impressed with what I've heard about the reactions of people on the scene; they're in the best Jim Macdonald tradition.
For Portland people worried about the Sellwood Bridge: the best course is just to keep your eyes on the traffic when you go across. Looking at the pieces peeling off the bridge will only lead you to dark thoughts of disaster to come. If denial doesn't help, use the Ross Island Bridge instead.
My God. Words fail. Given the extent of the devastation, if the final count is really only seven, it's damned lucky.
As with the hours after the World Trade Center, I am so grateful for the check-in area on the web.
Here in Scotland, I turned on the morning news at 6:30 and the bridge collapse was the first and biggest story. I knew that son Adam and wife Betsy, kids, plus John Sjogren and girlfriend were even then in the air on the way here.
So I was able to relax on that front. But then of course I started worrying about all my many Minn. friends. Various websites helped. Still need to know about the rest of the Pucci clan, but sure that Betsy will know about that and will tell me when they get here this afternoon.
Jane
What exactly happened: excellent visual storytelling from the Minneapolis Star-Tribune.
(And yes, they label the non-collapsed bridge the "10th Av. Bridge," so Elise and Avram were both right.)
On cells phones. If you have a tower connection, but you can't make a call, you can often get a text message through. SMS runs on the control channel, it doesn't need to setup and tear down a full voice connection for the message. Cell networks are built around having many phones talking on the control channels, to track what phones are in what cell at a given moment.
But the better answer is "do they *need* to know this bit of information right now?" And often, even the message "I ain't dead" isn't crtical.
"I'm not dead, but I might be soon..." is, but an hour's extra worry is an annoyance, not a critical problem -- esp. if the calls you are trying to make keep the person who's in real danger from calling for help.
So. In an emergency, ask yourself -- does the person I'm trying to contact *need* to know what I'm going to tell them *right now.* If the answer is no, wait until the comm crunch has cleared.
#76 Edward Oleander: Thanks muchly. Dive rescue was exactly what I was wondering about...
I passed that Star Tribune diagram to the folks over at Wikinews, and now they're looking into making a free version of it for their article.
Incidentally one of the passing comments they had in the IRC channel was:
"07:34:34 <DragonFire1024> whay does FOX News have to lie: The bridge was NOT ruled structurly deficient"
Thought some of you might find that amusing. ;) (And on an even farther, completely unrelated tangent, this article might be entertaining.)
I must say, the press conferences from both Hennepin County Medical Center and from the Minneapolis police are very impressive. People seem to really know their stuff and be covering every angle I can think of (and then some).
Neil Gaiman's been listed as "okay" on the check-in page for quite some time. We're still awaiting word on some local fans.
I've now gathered all the links I've posted in one place with more to come I'm sure.
I had the same thought as George @50 re: disasters of this magnitude. (And actually, every time I drove the Bay Bridge, or the route off of Cesar Chavez to downtown, my mind would inevitably run the "What if there's a big earthquake right NOW," scenarios. Also, a few months ago, they had a major overpass collapse in the Bay Area right near the Bay Bridge when a tanker truck full of gas crashed, exploded, and then proceeded to burn down the overpass that was directly above it. Fortunately nobody got hurt in that one though....but it's easy to imagine the toll had the overpass been crowded with folks. As it was, transit in the Bay Area was pretty affected, and the repairs--not cheap.
I can imagine the impact with this incident will be felt for some time in the Twin Cities but it looks like the people on the ground are acting intelligently, so hopefully the reconstruction and revival will go well.
My thoughts are definitely with the folks of the Twin Cities at this time. I'm a little selfishly glad that everyone on my F-list has checked in BEFORE I heard the news--I didn't even have time to worry about any of them. Stay safe, folks.
"Between 2000 and 2003, the percentage of the nation's 590,750 bridges rated structurally deficient or functionally obsolete decreased slightly from 28.5% to 27.1%. However, it will cost $9.4 billion a year for 20 years to eliminate all bridge deficiencies. Long-term underinvestment is compounded by the lack of a Federal transportation program."
First off, I'm a civil engineer, licensed PE, working as a highway design engineer. NOT a bridge engineer, but I work with those guys all the time, every day, so I'm familiar with what goes into a bridge.
That quote above is very, very misleading. A bridge can end up on the "deficient" list for something like too-narrow shoulders, old bridge rails, bad pavement, narrow lanes, etc, that don't mean "it will fall down if nothing is done soon". Not saying all bridges are ok that are on that list, just that not ALL of them are like that.
RE: this bridge collapse. Eyewitnesses said it was groaning and shaking right before it collapsed. To me, that sounds as if it had a failure in some critical member (and in a steel truss bridge, ALL the members are critical) that cascaded into more and more members as they couldn't take the extra stress. I don't think the work on the bridge caused it to collapse, or "heavy traffic". Even cutting a bolt by mistake shouldn't have caused this, given the high factor of safety built into every bridge. No, something gave way that shouldn't, and the rest of the support members couldn't handle that sudden extra loading.
The Washington Post got hold of the latest bridge inspection report that said there were signs of fatigue in structural members, but nothing to warrant immediate replacement.
Which makes me wonder; was it inspected completely (metal truss bridges are maintenance whores), did they inspect 'nearly' all the bridge, or just representative parts of it (i.e. the easiest to reach portions)? If they did inspect all the bridge, then did the engineers realize that a truss structure is stable only as long as all the members remain intact, and one failure (given deterioration everywhere) can lead to a catastrophic collapse?
Or, did the inspection report deliberately downplay the severity of the fatigue so as to not force the state to spend hundreds of millions of dollars they didn't have to repair/replace the bridge?
This article says that there are 20-30 people still missing, a number of cars underwater underneath the bridge, and that the road crew had been working on the joints of the bridge.
John #90: If they did inspect all the bridge, then did the engineers realize that a truss structure is stable only as long as all the members remain intact,
How likely is this? I mean, I know this from my structures lectures, and I was an aeronautical engineer (although I don't do it professionally). Is it really plausible that you'd have engineers inspecting a bridge with so little knowledge?
I understand that the maintenance works were on the bridge deck. I'm assuming that whatever they were doing there wouldn't affect the primary structure, unless they accidentally damaged it in some way. Or managed to tweak the bridge's resonant frequency in a bad way.
Stefan @63:
With Bush, we'll get some trite expressions of sympathy and some bluster about building the bridge bigger and better.
That and the Republican governor of Minnesota vetoing a gas tax that would have helped pay for infrastructure. I wonder how long the higher taxes = bad equation will hold up when you add death and destruction to the math.
#68 CaseyL
Boston's Big Dig is continuing in the news.... the good news and the bad news about modern design and engineering, is that with all the high resolution modeling, designers don't do the level of overdesign/overbuilding that enabled e.g. the Empire State Building to be essentially undamaged from being smashed into by an airplane.
Engineers used to have to use much larger amounts of safety margin in their designs, because the slop factors regarding how "safe" something was were larger... and when in doubt, overbuild/make stronger.
The nasty thing about modern design, is that it doesn't allow for implementation errors... or trying to speak English instead of "you have been working with too damn much badly written engineer-generated stuff!," people make mistakes, designers made bad assumptions about e.g. "manufacturability" (oops, too much geekspeak again... there's what the design expects, and then there is what can actually be built... one of the most representative examples was commercial defense contractor versus MIT Lincoln Lab, and I heard -both- sides of the stories.... commercial defense contractor: "Lincoln Lab designs equipment it takes a Ph.D to manufacturer and maintain." Lincoln Lab, "If they were competent they wouldn't have any problems building it!"
Reality check--MIT Lincoln Lab designers almost all have at least masters' and most of them doctorates, and the technicians who do most of the equipment building (some of the designers have made stuff, but it takes time away from designing; one of my old college dormmates when he worked there, who was a very hands-on designer, was frustrated for months at the lack of a tech meaning he had to build the hardware himself, which meant taking time away from his design work) have bachelor's degrees. They do precise specification of tolerances--tolerances which commercial organizations have trouble meeting on production lines--Lincoln Lab is an R&D outfit, not a production facility, and works to narrower tolerances than the commercial world... so, Lincoln lab designs assume a higher level of skill and stricter tolerances than the commercial world, while the commercial world looks at Lincoln Lab and sees a bunch of MIT academic-world R&D people with no concept of commercial realities and capability and limitations. The Lincoln Lab types don't allow for commercial organizations being sloppier than the techs and designers at MIT/less able to work to very precise narrow tolerances, and the commercial types are annoyed that Lincoln Lab doesn't take into account what the tolerances that commercial productions lines are, and that ordinary mortals working at defense contractors aren't going to achieve on a production line what R&D techs overseen by PhD designers at MIT, can do on experimental and prototype equipment.
Getting back to bridges and other things--people make errors doing things, and sometimes the errors are deliberate--a contractor just agree to cough up $40,000,000 or more for deliberately using substandard concrete in the Big Dig. That is ONE of the causes of the tunnel leaks--corrupt contractors putting in lower quality material than the design calls for.
Then there's the epoxy, one of the causes of a failure that killed a woman some months ago, the epoxy used was not the correct grade needed for the application, and it failed, and the bolts failed, and down came the now-unbolted panel onto the car.
There's the originally-called-the-John-Hancock-tower, of which the lawsuits resulted in -sealed- documents determining the causes of that building's problems sending glass panes sailing down into the streets of Boston... some if it may have been that the design was one which was impossible to be constructed to the as-designed tolerances, there were also rumors that the pile driving wasn't done as designed, and there were issues about the design, too--exactly what happened, again, was kept -secret-....
But again, modern design, there is the issue that there is the design, and there is the issue of what peope build/can build/errors in materials, tolerances, putting things in backwards, inspection (things don't always get properly inspected, and some things are almost impossible to inspect properly), fake paperwork... how much can/should be allowed on design, to accommodate "the contractor is going to use substandard materials intentionally or by fraud from the subcontractors or by unintended happenstance," the labor makes minor mistakes while constructing things, etc.?
But back to tunnels--the Big Dig involves mega-engineering. But it leaks... a lot of that is from not enough margin to allow for incompetence and fraud, along with having slime like Bechtel management controlling things and the Republicraps calling the shots that gave slimeball Bechtel the control.
If Seattle-Tacoma want to put in a tunnel, there's the experience of The Big Dig to consider...
Puala L @ 94
Leaks in tunnels ... part of the Red Line tunnel in downtown LA leaks. Seems that when they built the first phase of it, when they installed the semi-permeable membrane that was supposed to keep moisture out, and let it flow out from inside, they installed it wrong side to. So they have a tunnel section where moisture comes in, and stays in. (I have an opinion of that kind of construction, which can't be printed.) They haven't yet figured out a way to moisture-proof the outside of the concrete tunnel. 'I don't woory about lava in the subway, just floods.'
The bridge on route 2 in Cambridge over the railroad tracks near the Alewife MBTA station has never been anything OTHER than "deficient" from the day that Cambridge forced the state to limit it to being two lanes in each direction... it's inadequate in capacity for traffic, and was from the get-go, the day it opened it was deficient, even though it was brand new bridge and structurally sound...
There's "deficient" because something is structurally flawed, "deficient" because the maintenance is creating flaws, and "deficient" because it's in the wrong place, the design has issues for traffic flow and capacity that were INTENTIONAL as with that bridge in Cambridge, etc.
It's possible for something to have structural flaws and be safe--ugly additional supports to prop something up, for example, that take the load off the flawed part, or for there to be design flaws that additional support compensates for (for years, the roof of Kresge Auditorium at MIT was covered with lead, that annually the flowed down load got trimmed off, and perhaps melted, and reapplied to the top of the dome, to compensate for design flaw which generated a crack in the roof, until eventually the building got a new domed roof replacing the flawed design one...)
CNN has security camera video of the collapse. It looks like the failure point might be to the right of the picture. I clearly shows distinctly the failure of the center section, then the approach sections.
@97 Argh. That security camera footage doesn't show where it started, only where it didn't. But it clearly explains the part of the bridge that fell onto the railroad tracks.
It looks to me like the side that started it all fell slightly to the side, so I wonder if some of the bracing failed, starting the box of the truss to rack sideways.
Last night on MSNBC, Olbermann talked to some kind of expert (I didn't note exactly who he was). The guy mentioned that he's in the Northeast, where bridges were recently evaluated and found to be in very poor condition. Olbermann was stunned. I just thought, "Old news." In Massachusetts, anyway, they rechecked all the bridges (as I recall) a few years ago and found a ludicrous number of problems due to lack of maintenance or regular inspection. There hasn't been money ... and there still isn't. The story just got old and forgotten.
I want states to add a huge gas tax for bridge remediation.
But several years ago, on a three-day weekend, a policeman noticed that one of the bridges on the north side of Boston had a large drop at one of the seams. They shut down the bridge, causing backups for tens of miles, I think. A lot of people were cranky that the bridge was shut down as a precaution when officials weren't sure it would fail. I thought it was a pretty smart decision, and right now I'm loving the policeman who reported the condition.
Eric, there are eyewitness accounts to the effect that one side failed first, then the rest went with it. (There are others reporting what looked like concrete dust being blown out to the side as the first noises occurred.) I agree, this video does not show the failure itself, but it pretty much identifies were to start looking for evidence of the cause.
Patrick, one of the reasons we call the Cedar Avenue Bridge the 10th Avenue Bridge is because we call the MN-77 Bridge the Cedar Avenue Bridge. Hope that clears the whole thing up.
Along with the Cypress structure/I-880 collapse, I still remember the Sunshine Skyway collapse (following a freighter hitting the bridge). It's a little hard to forget, since the state turned long sections of the old bridge into what must be the world's longest fishing piers when they built the new bridge. Every time I visit my mom and go over the new bridge, I look over and see the remains of the old.
OOps. My link-fu is weak, apparently.
It should be http://www.johnweeks.com/bridges/pages/mn03.html
for the MN-77 Bridge link.
Drat it all, it won't let me post the link to the picture. I must be doing something wrong. Text keeps disappearing as I preview it.
Going to go do something constructive now.
If Seattle-Tacoma want to put in a tunnel, there's the experience of The Big Dig to consider...
Oh, yeah. Believe me, the Big Dig gets mentioned quite a bit - in a cautionary, not exemplary, way.
Folks, we've been coasting for 20 years on not maintaining things as they were designed to be maintained. Bridges, airplanes, school buildings, sports stadiums... if there's no money to be made doing it - if, indeed, it's going to *cost* money and cut into the bottom line (or, worse, if it means raising taxes) - then it just ain't gonna get done. And all the structural bills are coming due at once.
Jakob #92:
The inspectors looking at bridges often aren't engineers; they are state personnel trained on what to do, what to look for and how to fill out the report. MNDOT may have engineers inspecting their bridges but that would surprise me if they did.
RE: modern structures built to closer tolerances and smaller safety factors due to better design and materials. Wasn't this bridge built, though, back 40 years ago? This structure should have been designed with redundancy all through it.
Looked at the CNN video; it doesn't really tell me anything that could lead to finding out what happened (other than the center span didn't snap in two in the middle and fall). Not seeing the end to the right, which is where the collapse started, means we don't know if it buckled near the pier, slipped off the pier somehow, or what.
John (90):
"RE: this bridge collapse. Eyewitnesses said it was groaning and shaking right before it collapsed. To me, that sounds as if it had a failure in some critical member (and in a steel truss bridge, ALL the members are critical) that cascaded into more and more members as they couldn't take the extra stress. I don't think the work on the bridge caused it to collapse, or "heavy traffic". Even cutting a bolt by mistake shouldn't have caused this, given the high factor of safety built into every bridge. No, something gave way that shouldn't, and the rest of the support members couldn't handle that sudden extra loading."Thank you! There was no way that jackhammer vibrations or bumper-to-bumper traffic could have taken down an otherwise sound bridge. Suggesting that resurfacing operations might have done it was even dumber -- not only was it the wrong magnitude of fault, but the road surface was visibly the only part of the bridge that held together.
My guess when I saw the former bridge was that one section had collapsed and the others followed it down, the same way that one standard coming loose can take down an entire wall-to-wall bracket-and-standard shelf system.
That was interesting, about all the members of a steel truss bridge being critical. They always look so squared-up and sturdy.
Margaret Organ-Kean @78, believe it or not, the WS-DOT bridge inspection people have no agenda in "making things look worse" since their inspections are primarily internal documents used for setting priorities on maintenence, repair, and replacement. That the politicians and newspapers filter them to the public through their own lack of structural engineering and mathematical skills is where the bunkum comes in.
I sat through twenty years of squabble down here about the 4th Street Bridge over the Deschutes at Budd Inlet; luckily, we were close enough to the epicenter of the Nisqually Quake that it took that bridge out of debatable status without injuring anyone. It was in slightly better shape in the matter of concrete and steel wear than the south entrance to the Viaduct (which is being repaired, now, independent of any other outcome).
Why the Roman Empire is better than Gorge Bush's Amerika:
1. Roman roads, bridges, aquaducts, sewers, and even some buildings are still extant today and many of them in everyday use
OK, label this completely premature and underinformed speculation . . .
Looking at the photos and the visual that Patrick referenced, it appears that the video I linked to above is on the western or downtown side of the river, looking across to the eastern side. What we see is the failure appears to occur to the right of the picture, at the western side of the bridge. The bridge snaps off rather cleanly at the eastern support, and you can see the straight edge of that clean break through the dust, until the now unbalanced load from the rest of the eastern approach pulls it over.
Looking at the whole bridge from the north you can see the clean break on the eastern side clearly on the right, the central span looks like it dropped and hit pretty much in one piece, but the western side (to the right on this picture) looks like a mess.
Here is a picture of what looks like that eastern side where that clean break is quite visible -- this matches what is seen in the video.
The western pier shows a very different story. The break appears to be ragged and violent and you can see that the bridge frame has been twisted over flat -- completely off it's support, in fact.
I wonder if when the cause is determined, if it will involve just this area of the bridge.
Whoops, one too many if's on that last post.
John @105, the Bridge Inspectors I know have usually got ASE degrees (paid for by the state and focussed on bridges). Strangely enough, people with ME degrees are not especially eager to take jobs which involve tedious and meticulous work and high levels of physical risk (from being attacked by nesting Perigrine Falcons to being whacked on the bottom of a bridge during an earthquake- there's a BI in a persistant vegetative state from injuries incurred in the Nisqually Quake). They couldn't design a bridge from the ground up, but they are experts at what makes bridges fall down.
But there are a whole lot of damned bridges, they can't be inspected daily, and some things, especially metal fatigue, don't give a lot of warning. And then there's the problem that bridges that were designed 40-60 years ago, using what were then novel materials and techniques, are now at the point where they are showing unexpected problems. The I-90 and Hood Canal floating bridges sunk when a combination of materials degradation and wind load overcame their designed bouyancy, for instance.
Finally, there's the Silver Bridge factor: flawed materials, included in the bridge construction due to incompetence or malice, failing catastrophically on a bright afternoon. It's a lot more common than Galloping Gertie, which was a straight failure of engineering imagination to take the effect of cross winds into account.
Teresa,
A truss is a very strong structural design; it can withstand forces a lot greater than any of the individual members could handle because the forces are spread out among all those segments. But, it has to stay intact; if, say, a lower tension member failed, the other members could be overloaded to the point that they'd fail too.
That CNN video is so frustrating. If the start of the collapse had been in the screen, that could provide a clue as to what started the failure. If the deck just suddenly fell in an intact piece, then something caused it to slip off the pier holding it up. If it buckled, then that would be similar to a structural failure in the truss itself. Either way there should be evidence remaining that the investigators will find to determine what happened.
John @ 112
It makes me want to post a simple load diagram somewhere. Maybe several, for the various truss types, with the same overall load. (The best part of statics class, IMHO.)
Scary, scary stuff. I ride (rode) my bike under that bridge almost every day.
The folks pitching in and the emergency responders from HCMC (my employer) and elsewhere were amazingly efficient and brave.
Apparently they've decided it's safe enough to send divers down.
P J Evans #113
I know what you mean; trusses are odd creatures and force diagrams often explain better than trying to describe what's happening.
#109: are you sure the bridge started collapsing from the west end? If that's the twisted end, then the center span did not just slip off that pier; it got pulled off and took the western end span with it until everything tore apart. A failure in the main tension members somewhere in that truss might have done that; the deck would buckle and drag the nearest end off the pier.
The eastern end was probably seated on the pi
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