I-5 Bridge collapse, Mt. Vernon - Burlington WA

Fuzzy where the bridge is located, can you tell us about the demographics?
Is it a Poor rural area of the state with pass through traffic, a wealthy suburb, etc
Is it densely populated?

 

Heck... I lived in Western WA for ~9 years and I don't know. Definitely people pass thru there on the way to/from Canada.

About the only major population centers in WA I can think of includes the Seattle metro area, the area around Tacoma and Eastern WA (e.g. Spokane). I never even ventured to Eastern WA.

 

I beleive that in many jurisdictions, with proper axle configurations 105,000#

Icarus

 

It is only one section of a 1100 ft bridge, ~100ft. The question is, does only the one span need To be replaced? 16 mill seems to cheap even at that.

Icarus

 

One final note is, because of the geography, there are only 5 bridges (total) across the river between the cascade crest and the salt water, two in the city of Mt. Vernon carrying local traffic. There is one more bridge downstream near the mouth of the river,about 15 miles down river, through a big detour, one on state hwy 9, a long and windy rural detour, and one in Darrington, about 40 miles east, with a huge detour.

The point is, there are not very many alternative routes, and non that are easy, given the volume of thorugh and local traffic. It's not like one can just exit, drive a bit and cross somewhere else. The two local bridges are chock a block full of local on a good day.

Icarus

 

It seems to me with a small rural population with limited business base a toll road may not work, and perhaps the financial burden lies with the county, state and Fed.

I'm sure tourists this Memorial Day have changed plans to avoid that road. Every day that road is in disrepair commerce is reduced. Time for gov to get moving on a solution

 

I understand the correct term is "fracture critical" meaning one part fails, the whole structure collapses. Non-redundant structure.

Bob Wilson

 

Mt Vernon is the local commercial center for farming and dairy, primarily tulip farming.

It is not a suburb of anywhere else, it is 60 miles south to Seattle, and 80 miles north to Vancouver, BC Just north of the bridge is a Mall catering to BC traffic. The Skagit river bed at the bridge is 7 feet above sea level, I would not be surprised by tidal back flow from Puget Sound, but it should not be salty.

You can see a 12 hour wave in the data.
It is somewhat a transportation hub, the North Cascades Highway is just north of town, the detours I have seen all use parts of it. SO Mt Vernon is the first chance to go east in the US for highway traffic. Almost all San Juan Island traffic goes west, just north of town.

The Whale watching company I use is panicing, they are cut off from customers.

 

This from my experience in working in a shipyard, in Seattle no less, now decades past:

The red/orange color where the gray paint has come off the distorted structure is too orangy and consistent to be rust. It is most likely 'red lead' primer. It is widely used in steel ship building as well. It is used at initial construction, and in long term maintenance programs of steel structures. If rust is present, the metal doesn't have to be sandblasted to 'bright metal' for it to strongly adhere. Red lead forms a chemical bond with a light rust coating. It is a rather 'soft' coating due the high content of 'red lead' particles. In the pictures above, it has remained adhered to the underlying structure although the harder gray top coat, 'paint,' has chipped off/flaked away where the underlying structure has been distorted.

By all appearances the maintenance of the surface coatings on the bridge looks from this distance to have been at least adequate, if not good or better. There is no visual evidence of running rust smears on the individual members or at the undistorted joints.

Rust in the riveted joints would be especially bad. Water that gets in between the various pieces would lead to hidden corrosion enlargeing the rivet holes, or more likely the 'necking down,' that is reduction of the cross section, of the rivets. In either case, failure of the joints themselves becomes likely, even under design loads. Reapplication of red lead over time at the joints is meant to allow the coating to fill any small crevases/fissures that might occur between pieces of the joint that might occur over time and keep water out of the joint.

FWIW, red lead primer is restricted access, it is legally sold only to commercial customers. IIRC, it goes for something like $250 gallon.

 

Consider that the GOP legislature in Washington is about to kill the rebuild of another I-5 Bridge over the Columbia. An obsolete DRAWBRIDGE that stops US West Coast traffic several times a day as well as being a traffic choke point when it is working as well as being crumbling.

The same goofballs who plan to NOT raise gas tax but add a tax on hybrids for not using oil that will raise no money just add discouragement to people to use less oil.

 

16 mil is not an official number resulting from any worked out bridge replacement analysis. It was someone's guess issued to answer the incessant media question about the cost. The media uses that number to broadcast how bad the disaster is. The demand this number the same day the disaster occurs. Figuring out the real cost takes weeks after a complete analysis of what needs to be replaced and what bridge standards will be used. Neither of these actions has been performed.

Unfortunately, this "16 mil" run headlong into the old adage "the first lie is the easiest lie". When the real cost gets added up, it will be substantially higher. This only causes problems for the legislators since it looks like they are incompetent (which may or may not be true) since the cost the entire public remembers is the initial random number and the actual cost to the taxpayer must include everything. I could easily see 16 mil being needed just to fund all the road work and traffic management necessary to handle all the rerouted traffic over the long span of time the bridge is out.

Things to think about:
1) Were other spans damaged by the shock. Will they need to be replaced?
2) Was there foundation damage requiring the supports to be upgraded/replaced?
3) Will the detailed inspection uncover major upgrades needed just to allow adding a replacement section?
4) Will the decision be to make a long lasting replacement section or replace the whole bridge while using a very limited temporary section?

I do not know the answers and the person stating 16 mil did not either.

 

FL I agree the estimate is garbage without an inspection

 

Clearly you hve not spent much time in WA of late. The I5 corridor from PDX to the Border is nearly one long megalopolis. Going north from Seattle, there is virtually no break in urbanization until you reach into Skagit county, with people routiney commuting from Stanwood (~50 miles north) to metro Seattle. Mt Vernon/Burlington/Anacortes/Sedrowoolly have probably doubled population in the last decade.

Whatcom County, the last county before the border has grown dramatically I 40 years, coincident with the opening of the last stretches of I5. Bellingham was ~35,000 in 1970 is now net 100k. Total Whatcom population has risen from under 100 to close to 300k in that period.

Couple this with the huge growth in the lower mainland of BC and the huge number of crossings every year, and you have a huge traffic bottleneck in the 2 lane (each direction). I am not an advocate of "more lanes" but recognizing reality this route is over used. I suggest putting more trucks on the rails, rebuild the inter urban rail network of public transport that serve the area before the days of have freeway, increase the frequency of inter city trains (Amtrak) to get as many cars off the road as possible. Of course this is pie in the sky dreaming, since Americans are loath to give up their private cars. I get that!

Bottom line, to call Western WA rural is only true in some comparitive sense. The I90 corridor between Seattle and Spokane is much the same, huge growth in population, huge growth in traffic, epecially truck traffic. Can't we figure out how to get just in time freight back on trucks?

Icarus

 

Anacortes WA with a population of 15,000 relies on tourism. This bridge fiasco will divert tourists to other destinations. You can expect businesses and employees to suffer.

 

In point of fact, you don't have to tax the I5 bridge to get to Anacotes. You can get off 10 miles early at Conway and take the Fir Island bridge (one of the suggested detours)

Icarus