But in many places (especially in the east) the system co-opted existing roads and bridges so there were some low clearance situations.
The adopted criteria provide vertical clearance values for the various highway functional classifications (Table 19). These criteria are set to provide at least a 1-foot differential between the maximum legal vehicle height and the roadway, with additional allowances for future resurfacing. These clearances apply to the entire roadway width (traveled way and shoulders). A formal design exception is required whenever these criteria are not met for the applicable functional classification.
The specific standards for vertical clearance adopted for the Interstate System maintain its integrity for national defense purposes. On Interstates, the clear height of structures shall not be less than 16 feet (4.9 meters) over the entire roadway width, including the useable width of shoulder. In urban areas, the 16-foot (4.9-meter) clearance shall apply to at least a single routing. On other urban Interstate routes, the clear height shall not be less than 14 feet (4.3 meters). A design exception is required if this standard is not met. Exceptions on the Interstate must also be coordinated with the Military Surface Deployment and Distribution Command Transportation Engineering Agency of the Department of Defense.
In restrospect, which does no good other than to guide others, the load needed to detour to one of the parallel bridges or take an alternate route.
However again, it was probably not likely to be going through Mt. Vernon proper as the detoured are now and the cargo would possibly be a political football given the howling over 'megaloads' being permitted over Hwy. 12 in northern Idaho.
As for the claim of rust, the bridge was inspected regularly and not found to be structurally deficient, just OBSOLETE. This does NOT mean it was ready to fail but that the design was outdated and in need of replacement at some point.
The Alaskan Way Viaduct inside Seattle is rated far lower than this bridge was and THAT has been getting retrofitting and replacement.
The reality of it all is that Washington state is not any different than the others. People hate taxes but love getting places on the roads and the balance has shifted from fixing old viable roads to just building new ones sometimes, only to revert to constant patching of potholes and little else. Washington has some of the worst budgeting woes in the West...not a California but they are NASTY and they had to balance the budget as it's a constitutional mandate just like it is in most every state,
Eisenhower didn't build the Insterstate system for the MILITARY...he saw the benefits of the Autobahn and other important European roads during the war and used Communism as an excuse to get Americans to stomach the project. When all the nice shiny cars and suburbia, ease of travel with cheap fuel followed that there was no turning back at that point.
Now the Interstates were built for high speed and quick travel and down the road (not a pun) this meant lots of straight and monotonous driving that pacified drivers into a false sense of confidence, complacency and carnage from bad habits and fatigue with no real chance of those Utopian automated roadways of car shows ever occuring...folks like to control their vehicles (one REAL reason public transportation isn't very popular in the US).
Lots of work to fix dangerous curves and build warning 'rumblers', eliminate certain entrances and exits to prevent wrong way driving etc and not enough time spent replacing bridges and overpasses due to the massive traffic headaches (until it fails and you absolutely DO have one).
We were brought up on inexpensive travel and learned to ignore the dangers until now, and may well forget again. Still, as suggested by the content of another member's comments, expensive fuel isn't the answer and won't teach any lessons. The rest of the world is no different than we are. We introduced cars to them and while they have their own systems they still feel that cars are not only necessary (some truly are) but somewhat vital to the quality of personal living. There are persons with more practical means in mind, but humanity has spread out so far from central living than ever with transportation and our cities are crammed to where it made production less profitable and in turn the cheaper labor areas have less of these problems, people still leave the farms and villages to work in the cities andthe same patterns of blight and dysfunction occurs over and over.
Does it mean I'm going to forego seeing my relatives until they are dead though? I'm not at all into camping.
Thoughts for you.
The age isn't the biggest factor there and the structure was extensively repaired and modified over the years. The DESIGN of this bridge was the obsoleting factor.
The load was not proper for it and evidence of other accidents shows yet this event was so catastophic it caused failure where other incidents didn't and in fact could be repaired.
Also to consider: the security camera on a lot facing the bridge on the other side clearly demonstrated the speed of the failure and perhaps points out excess speed added to the equation?
Would the driver have cleared the span otherwise is the implied question.
I had put off complaints that the huge equipment Idaho had initially allowed to move along Hwy. 12 would damage the road at that speed but them again the condition of bridges, even at a scant few miles per hour could have been a problem for the streams.
This load was at 20' if I remember it right and maybe the left lane might have worked but also remember that the truck driver is following a pilot car that is tryig to guide them safely and they have to rely on the pilot's judgement. The top ~2' of the load was damaged and suggests it was just barely over, actually! The force of the impact at whatever speed it was did not have to involve a large error and the design itself held the flaws that made it collaspe as severely as it did.
I suppose that we can speculate this for ages but it's really for the state and NTSB to figure out and they have a lot of work to do.
Meanwhile a two train wreck took out an overpass in the midwest and fortunately casualties seem minimal there as well but that was not a design problem, it was a trainwreck breaking the bridge.
Well, thanks to this one incident, the interstate traffic will now overflow onto some generally quieter roads that are more frequented by non motorized traffic, greatly affecting their personal safety. How's that.
Not many involve 70,000 vehicles running through the middle of a small town. That must be a treat for the kids.
Truck load struck the girders with around a million Newtons of force. That means your average 220 pounder (cycle + rider) hauling butt at 22,000 mph. I suggest we all slow down and not get the NTSB too excited.
This bridge has stood for many decades, probably due to stricter regulations with a lower minimum set height. Today, taller loads were allowed to cross this bridge as long as there was a pilot car equipped with electronic height warning sensors proceeding the loaded truck, and I know this technology did not come about until recently.
While the technology may be new, we've been safely transporting oversize, (wide or high or both) loads for decades using pilot cars and follow cars. Unfortunately improvements in technology often don't bring about the expected improved outcomes predicted because humans rapidly adapt to them and lower their attentiveness making it a zero sum game. Someone here flubbed, and the investigation will try to answer why and how it happened, and possibly have recommendations for "improvements", but don't hold out for miracles.
The northeast is loaded with low clearance overpasses, and over the years we've moved form simple signage, to telltales, to crash bars, to radar activated lights and sirens, and folks still manage to run into them. There's no substitute for driver alertness, whether it's avoiding low clearances, or bicyclists along the road.
Maybe within a few years there's be crash avoidance systems for trucks similar to those we're seeing come out for cars, but I'll venture that even then folks will figure out a way to have accidents. Don't expect too much from technology or regulations as long as humans are involved anywhere along the way. As has often been said, "nothing is foolproof because fools are too ingenious".
From the early reports (story may have changed since) the driver changed lanes from the one he was directed to (human error), so while he might have otherwise fit under a crowned clearance, now he didn't.
If there had been one maximum height limit, set to the lowest number, then this incident would have not occurred and would have been a moot issue.
I don't have a clue where that comes from. The clearance stated is almost always the minimum available, and where I've seen multiple signage was at toll booths, where drivers are split into multiple lanes to speed the flow at the payment booths and not all may notice otherwise.
I was watching the coverage and this man was interviewed who said he was PASSING the load while ON THE BRIDGE, and from what I could gather he probably shunted the driver into that lane not having a clue about anything except the notion that the left lane is 'passing lane'.
Those of you who state that the driver was supposed to be in the LEFT lane and jump to blame the pilot or driver immediately seem to have missed something. The average commuter sees an oversized load sign, or ANY truck load and feels like they need to pass that truck PDQ (and recent, regular news reports of improperly secured loads hitting cars and badly injuring or killing motorists only make this feeling worse).
Motorists have no idea about such things so what the permit said or didn't at this point may have been rendered moot by one foolish person driving neither vehicle.
As the NTSB and WSDOT have been saying, armchair science needs to be suspended and cold, hard facts must be INVESTIGATED.
Oversights and really alarming things concerning crossings are still nothing new. There was a 1927 bridge at Payette, Idaho near me restricted to one lane always-it's twin, if any was replaced years ago but you could see spots at the edges that had NO BEDDING and axle limits were low. This was a scary bridge to ride across on a bike! Drivers routinely did over 50 crossing it as if a game of chicken were involved. There were even scarier parts where the cross-structure was damaged badly on a section!
When the East Idaho Avenue overpass and I-84 interchange were torn out and rebuilt with a new layout some years back they did it one side at a time (it wasn't falling apart really, just inadequite) and one day I drove over the I think the bew half when to my utter HORROR I saw a person SITTING on the edge that was now without a barrier! When they finished a tall fence was installed to thwart jumpers, but how that person got there I still don't know nor understand why they did it...they weren't a suicide attempt, no reports came in about a jump either.
I can understand how this thread would naturally shift into this discussion but that still wasn't why I opened the thread. My point was that cyclists were under great pressure from overloaded traffic patterns forced on their streets by tragedy and how to alleviate the problem. To add to it all some businesses are doing exactly waht you could expect and tryng to drum up business at their drive-thru shops...
That could cause a lot of stop and go carnage right there but fortunately people seem more intent to get down the road and home.
There are many things to consider here that impact everything as well as cycling but they all go together in a place like NW Washington with it's massive automobile traffic.
Rollfast, here's an excerpt on Wash. load permitting:
"It is the responsibility of the permit applicant to check or rerun the route to insure it is free of overhead obstructions. WAC 468-38-100 http://apps.leg.wa.gov/WAC/default.aspx?cite=468-38-100
Pilot cars are required for any load that exceeds 14’6” in height. WAC 468-38-100
Pilot cars are to be equipped with a height measuring device to detect overhead clearances. The device must be extended between 3 and 6 inches above the maximum height of the load.
The pilot car must be far enough in front of the over height vehicle allow the over height vehicle to stop in a safe and timely manner if needed."
Washington State does not require minimum overhead clearance signs, until the overhead clearance happens to be less than 14' 6".
Here in California, I believe the sign requirement is for any overhead clearance less than 16', since I've seen a number of our older local bridges and overpasses being marked at 15' 5" (or more)
Having height clearances determination left up to one person in a pilot car will eventually keep leading to mishaps such as this one.
I can guarantee that some special load height provisions for this bridge will be made when it returns back into service.
Well the early reports are out and it looks like YES, the right lane was a problem as it was lower, too low...
and previous incident reports as recently as October 2012 indicate that the structure was a frequent victim of scrapes.
Now WSDOT has announced they will install a temporary replacement span with no overhead steel within the next 6 weeks (maybe June 15, the governor says) while they work to replace the bridge. OVERSIZED LOADS WILL BE FORBIDDEN...
Fortunately for transporatation authorities and commuters drivers have adapted quite well and things are a lot better than expected but it's still not bike paradise.
It is no wonder that there has not been any response from anyone regarding how cyclists can alleviate the "great pressure from overloaded traffic patterns forced on their streets by tragedy."
Or anything about cycling at all.
The title asked it and if you don't live there initially then it might not have much effect.
Since the permitting process seems to have been a problem that factored into the eventual accident and in the end it does make bicycle traffic much tougher for their residents the question ultimately could come to you in the end. You may live in a small city of under 30,000 and it might not be such a problem but what if the Great River Bridge were closed for some period or there were a disaster nearby or near Moline? You have US Route 34 running through the middle of town, Route 61 and what would happen if Quad Cities were closed due to a catastrophe? Would commercial transport be more reliant on short trucking to the railroad?
The town I was born in was at 25,000 population until the 1980s and SW IDAHO has more than TRIPLED in size over the last thirty years. The bottom corner of eastern Iowa might be quiet but this is the new Wild West and built from stem to stern with stupid anchored malls and houses from Mountain Home to Nampa and Caldwell and they jammed Everything next to the interstate here in beautiful Erewhon, Ontario, Oregon as well. With over a quarter million in the Treasure Valley I-84 is probably a bit more critical than Route 61 (although a singer or two might not agree).
But at some point you learn how important the overall network is and how it affects YOU in the end. You will need to address this.
And I figured that since I asked I should be trying to find things out and add whatever answers I could as well.
In the end all things affect you and I, the cycling public.