When entering a parking structure in the Big Smoke have you noticed how there is generally a bar of some sort hanging from a couple of chains that you are required to drive under? There is also a sign that advises you the maximum vehicle height that can safely park in the structure. But, because people don’t like to read signs, or they don’t have a good sense of heights and numbers, the hanging bar acts as a check. If there is a bump as you pass under the bar you know that you have bigger problems ahead. Time to back up and park somewhere else.
So what do you think would happen if a parking garage posted the correct maximum height sign but set the bar a foot higher? Do you think people would look at the sign and think that the bar is set too high? Or would they simply ignore the sign and see if they fit under? If they are driving a vehicle that is a bit higher, perhaps a pickup truck with a camper unit on the back, they would probably inch forward cautiously, and once they passed under the hanging bar, assume they are okay and drive into the garage. Surprise!
This is basically the situation on William Street in Parry Sound and the CN trestle where there have been three ‘decapitations’ complete and partial in the past year. As you approach the trestle there is a frame structure about 15 feet in front of either side of the trestle. The sign on the trestle says that the maximum height is 10’6”. That seems like enough information to warn the truck driver with an 11’ height to take another route. What would you think if I told you that the clearance of the trestle, where the trucks hit the trestle, is greater than 11’, offering drivers a considerable margin of error. But perhaps 10’6” is actually more reasonable. As you look at the photo below you realize that there is a drop down as the truck travels under the trestle but the box of the truck would still be at the higher road level. That would lead to an angle which might actually make it an effective 10’6”, even if it’s actually three-quarters of a foot higher directly under the trestle.
The problem is not just professional drivers not knowing the height of their rig, or not paying attention, it’s also the support frame about 15 feet in front of the trestle. This structure has a clearance of 13’. I can well imagine that a truck driver might cautiously approach this 13’ frame and, discovering that they are able to get under it, assume they can fit under the trestle. It’s a bit of an optical illusion the way the road dips down, suggesting there is more clearance than there is.
The answer it seems is pretty simple. Suspend a bar on chains under the two support frames at 10’6”, much as you see in parking garages. A truck would pretty quickly figure out that they weren’t going to fit if they heard a thump well before they ventured forward and tore the top off their trailer.
We have had three such incidents just this year. You would think that CN would have figured it out by now that something needs to be done.
Has the Town received a formal report from CN attesting to the integrity of the trestle? Three dings in the past year and many more over the past few decades could mean there is unrecognized structural damage. But, it seems the railways always find it cheaper to apologize and make repairs after the fact than practice prevention.
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June 16, 2017 at 7:25 am
I rented a truck not too long ago. I drove right under that trestle. I didn’t stop, I didn’t even slow, because, I realized afterwords, I subconsciously thought “oh, that’s only a thing for real trucks” . Somehow I didn’t think I was part of that category. After passing the bridge though, I noticed a sticker on the dash of my rented truck “Warning: Requires 11″ clearance”. I remembered that the trestle had said it was only 10’6″. Yet I had made it through! Clearly someone was exaggerating, I concluded. Some might call that “margin of error” , others might call it “wiggle room.”. Whatever, by including it, they think they’re being cautious, but all they’re really doing is training the people that such signs for don’t need to be taken very seriously – ” oh, I’m sure they don’t really mean that, I’m sure i’ll be fine.”. And they are fine. Till they aren’t!
June 16, 2017 at 8:24 am
It was your lucky day. That’s why they offer renter’s insurance.
Measuring the trestle height at the ‘strike points’ revealed that it is about 11’3″ or a couple inches more to the bottom of the leading edge of the trestle. That’s 9″ above the 10’6″ marked height. It’s probably a reasonable number to post given that in the winter the snow and ice might effectively reduce the clearance. It’s also likely that your truck also ‘fudged’ a bit with it’s height for exactly the same reason, erring on the side of caution.
The answer, installing hanging chains or a swinging bar, still seems the right thing to do. Even if a truck were driving too quickly to stop when they hit the dangling chain/bar they could perhaps slow down enough to minimize the damage. And a cautious driver with a truck height close to the stated limit could use the ‘early warning system’ to see if they might be able to squeeze through.
It seems strange that the CN hasn’t done something to remedy the situation since it would be so inexpensive. I wonder why the Town hasn’t demanded the change. Yes, the Town claims no responsibility for the trestle or the accidents, but they still have an obligation to the neighborhood to ensure there isn’t collateral damage resulting from a ‘decapitation’. Perhaps they are afraid to ask the railway for this simple safety improvement much less a report on the structural integrity of their many trestles in Parry Sound.
June 16, 2017 at 8:54 am
Oh I agree with you that the hanging bar would be a good idea.
But who would install it? Who pay for it? The town would probably be wary of doing it themselves because it would imply them accepting liability.
The train company probably wouldn’t do it, partly because to install the bar enough in front of the bridge would likely entail mounting it on town land, but also because they’re typical M.O. is to not bother spending money to change the status quo if the status quo isn’t really bothering them – regardless of how much it is a problem for others.
I think you’re right that the real concern here is the safety of that bridge: how is the structural integrity holding up? Those things are engineered to bear load from above, not lateral impacts from the side. Again, it’s the train company that should be on top of that, but see the point I just made about the status quo. The train companies aren’t the ones who have to bear the risk of driving under that thing!
Now, the town does have the job of looking out for the safety of its citizens, and so I think you’re right, maybe they should request a report. Unfortunately, if the town’s experiences with the road construction last year are any indication, they’d probably have better success calling up Putin and requesting a report on the 2016 election!