Rollfast

With the detouring and heavy usage of smaller routes and city traffic increasing around the area north of Seattle (Mt. Vernon) coming at the very worst of times (during a major holiday traffic period) I would urge cyclists in the area to exercise great caution in traffic as it's bound to be a huge mess.

Stay alert! No lerts were present in the pilot car or truck carrying the oversized load that caused the bridge failure.

dynodonn 

Looks like someone didn't do their homework on the overhead clearances along their route. Definitely going to be a costly error in judgment for at least one local business.

Rollfast

As I saw from KING5 coverage on NWCN the nearby non interstate bridge is taking increased, rush hour type traffic now and heavy trucks are being routed through town.

Do you mean the casino?

rydabent

Casual observation of the news reports show heavy rust on joints of that bridge. It hasnt be safe for a long time.

CB HI

I saw a news story that implied the drivers excuse will be that he was forced out of the left lane (where he had enough clearance) and into the right lane where his overheight load took out the beams.

kalliergo 

Forced how?

unterhausen

I'm fond of swimming and all, but it's probably better to stop rather than to change lanes and go into the water. Do they really allow trucks to go on roads where changing lanes means you hit an obstruction? I wouldn't have thought that to be the case.

CB HI

That was my question as well while watching the story. They did not give an answer.

unterhausen

it looks like the center is quite a bit higher than the sides, so if you can manage to take up both lanes a taller object would probably fit. I have seen loads with police escort, it seems like that should have been done in this case

kalliergo 

It was a permit trip. Washington DOT has the related paperwork on their website.

The truck was preceded by a pilot car, presumably with a "height pole" since load height was a known issue.

It's clear from the photos here that the upper right corner of the load (a shelter-like container for drilling equipment) hit a lower portion of the superstructure near the right side of the bridge.

Somebody overlooked an obvious danger.

It is notable that there is very little damage to the load, considering that it was subjected to forces sufficient to knock a 160-foot secion of an Interstate highway bridge off its piers.

Bekologist

Insomuch as most bicycle traffic going N/S at the same latitude on the West side of the Cascades is going to be on the Centennial trail, i'd say,

"Not Much!"

This bridge truly represents a "pinch point" at the slough; there are a very small number -like two - of acceptable alternate routes by bike at this spot in the state; any cyclist in the know gets past the slough on the Centennial trail and doesn't even have to think about traffic until they hit Arlington.

I'm sure local riders in the Lake Stevens area will see a lot more traffic on the 9, but that was never fun to ride to begin with. North King/Snohomish County will probably have a lot of traffic congestion this summer till they get the bridge fixed.

Wouldn't affect my riding past this spot in the state, the sensible Centennial route avoids the roads for 20 miles N/S of this location.

Greyryder

What's really weird about this, is that the beam that truck hit, are the ones that hold the sides parallel. They're not the beams that actually hold the weight of the bridge up. I just don't understand how dinging those center beams could have brought that bridge down, unless there was already something Very Wrong with that bridge.

All the rust is around areas that bent, when the bridge collapsed. I'd say that's recent rust, that formed after the paint popped off, from the deformation. Though, I agree that bridge was already compromised.

Brian Ratliff

With that style of bridge, each of those sections between pylons are separate. The road surface cannot support itself; the box structure of the beams above the road is in compression and stiffens the structure so it can be supported by the ends. If you take away the top structure, the road will collapse into the river. Apparently that bridge was not built to sustain damage; it is described as "fracture critical" which means it doesn't have redundant support structure.

dynodonn 

It'll be interesting to see who ends up at fault concerning the minimum clearance issue, whether the bridge was incorrectly measured or the trucking company hauling the wide load thought they could get away with a load that shouldn't have legally left the yard for the route it was designated to travel on.

yamsyamsyams

The truck driver is Canadian, I wonder if the Canadian trucking company will be liable for any of this?

kalliergo 

Yes. Weaken the truss superstructure by hitting/bending/moving a few elements and the whole thing sags, pulling the ends of the section away from the piers. All fall down.

Add years of deferred maintenance and little or no earthquake retrofitting and you get the proverbial disaster waiting to happen.

kalliergo 

It will be very interesting. Note, however, that the permit paperwork repeatedly insists that clearance heights are not guaranteed. See here:

https://www.wsdot.wa.gov/NR/rdonlyres...357/permit.pdf

and here:

https://www.wsdot.wa.gov/Projects/I5/...nt/default.htm

I think we can expect a big, expensive, drawn-out legal battle.

But, as Bek points out, few cyclists are likely to suffer much.

dynodonn 

Yeah, like that is going to stop a lawsuit.

kalliergo 

Did I suggest that it would? No, rather, I wrote this:

dynodonn 

Sorry, not referring to you personally, just the laziness in setting minimum height regulations, which only leads to incidents and the following finger pointing such as this one.

kalliergo 

No problem. And you're right. It's absolutely ridiculous that real clearances aren't known or communicated or verified in situations like this.

dynodonn 

In reading the permit link that you provided, the load was 15ft 9in high and without a pilot car equipped with height warning sensor, the load could only be 14ft 6in high. This type of setting leaves little room for error should the pilot car operator get it wrong or is too late in warning the following truck driver. To be considered safe while operating in the left lane, but not in the right lane is totally ludicrous.

kalliergo 

Yup. Take a look at the minimal damage to the load that took down this bridge:



There was a pilot car, but it's not clear whether it was equipped with a "height pole" (as they refer to those things).

FBinNY 

It is. Many bridges and underpasses all over the US have arched clearances where there's more head room at the center than either or both sides. They'll be marked with multiple clearance signs over each lane, and if done properly the sign will give the lowest clearance for that lane (which is usually at the edge). See article and photos here. BTW- The minimal clearance standard for the interstate system is 14' with most clearances more than that.

Normal motorists don't usually read clearance signs (which is why so many destroy bikes on roof racks) but a professional driver should be aware of their importance.

That said, there's a low clearance railroad overpass near me that's hit so often that lower edge of the Hi-flange is kept polished and rust free.

Jseis 

One of the last longer timber trestle bridges is being replaced down here in Pacific County. All on piling bents with no overhead construction and 80 years old and survived decades of log trucks, coastal traffic and a tsunami. The Skagit gets flood debris...probably had to have longer section spans than bents of piling allow to for flood debris flow clearance. A county engineer told me that "back in the hayday of highway construction steel bridge packages could be ordered base on width, span and load and they were delivered with all the necessary hardware....they all looked similar because they basically were.

There's a steel bridge on SR 6 over the Willapa that's been hit countless times by high log loads. A truck driver told me that it was it with high load a few years ago and a log stayed up in the girders. The bridge is still there though it'll be replaced over the next year for age reasons.

The girders sure looked modest in size compared to say the steel Rainer Bridge (STP rider go over it), St. John's (STP too) or Astoria-Megler though all three are really high spans & built stout. That Skagit Bridge doesn't appear to have much margin for failure.