This WSDOT simulation is really alarming.  Via KING5, the agency emphasizes that it was released due to a public records request and not to impact the election.  However, they make the case that it means we have to proceed on the deep-bore tunnel without delay:

“It is weak at its core and we must replace it as soon as we can,” said [WSDOT Engineer Jugesh] Capur.

Of course, what the video shows is that we have to remove it (and replace the seawall) as soon as possible.  Whether we replace that with another highway or not is another question.  The current plan envisions taking down the viaduct in 2015, not 2012 as the Governor originally pledged, to avoid traffic disruption in the meantime.

Remember: subjecting new highway projects to due process and environmental review: reckless disregard for people’s lives.  Leaving a brittle viaduct up to make sure auto trips into downtown are convenient: good transportation planning!

In other news, the memorandum of agreement signed last week by Governor Gregoire and Mayor Nickels contains no mention of overruns whatsoever.

Also: Skepticism about WSDOT’s motivations here and here.  My nuanced position on the merits of the tunnel is here.  I wrote the above before I saw that five viaduct “stakeholders” agree with me.

45 Replies to “Take Down the Viaduct Now?”

  1. As Dan’s piece on hugeasscity notes, none of the other potential viaduct replacement plans would leave the existing structure standing past 2012.

      1. Time to take it down? What do you mean? It’ll fall pretty quickly if you strap some dynamite to it, I’d imagine.

      2. Ben,

        I wasn’t meaning to be trite. I imagine the concrete would fall to the ground accelerating at 9.8 m/s squared. =) I just wondered how long it will take for planning, staging, take down, cleanup, etc… once they decided to move with haste to take it down, how long would it be before those surface parking lots under the viaduct look up and see nothing but sky?

  2. And remember this video was made by Parson’s Brinkerhoff which is one of the engineering firms which stands to benefit from any viaduct replacement/removal project.

    On the actual video, doesn’t look that bad, maybe 100 people dead, maybe 1,000 people injured. A typical week on the road in a car in the USA. (Remember approx. 44,000 people die every year in auto collisions)

    And if the seawall holds, there is much less likelihood of the viaduct collapsing.

    Still the timing of the release, the leak to the King 5 reporter to “request a copy” just before the election leaves one thinking that this is yet another political move by WSDOT to influence the result of the Seattle Mayoral election. Wouldn’t be the first time they pulled a stunt like this, won’t be the last.

  3. While I certainly agree the viaduct needs to come down due to safety, color me unmoved by the video. Essentially, the video is saying that for the animation to happen we have to have a longer, stronger, and closer quake than that of the Nisqually quake…which was easily one of the strongest quakes recored in Washington history.

    Had the simulation occured with a shorter, weaker, and further distant quake…that would be a different story. Take it down, but there doesn’t need to be any “urgency”.

    1. Continue that train of thought, “…there doesn’t need to be any [sense of] ‘urgency'”, and we’ll continue to delay the replacement until it is way too late. Why assume that it is unlikely that we won’t have a quake that would be equal to, or stronger than, the Nisqually quake?

      I’ve said it to others before and I’ll say it again. Those who are complaining about the tunnel and preventing it from moving forwards will be the same ones who complain and shout the loudest when a quake does happen killing and injuring people asking why wasn’t anything done sooner.

      It needs to move forward. I am not a fan of the tunnel, but the replacement has been debated and delayed long enough. Someone needs to put their foot down and just get it done.

      1. Mike,

        The point of the post above is to say that you can take down the viaduct without moving forward on the tunnel.

        The other tunnel options take down the viaduct sooner than the deep-bore.

    2. MattG, not to pick on you, but the Nisqually quake should serve as a reminder of the risk rather than justification for complacency.

      Seattle is at risk of a number of quakes far more destructive than Nisqually. This includes an enormous, infrequent, but possibly overdue quake from the Cascadia subduction zone ( ). The Seattle Fault in Elliot bay could also produce quakes similar in magnitude to Nisqually, but would be devastating due to the closer proximity ( ). There are many other faults in the region which, depending on the combination of magnitude, distance and type also put Seattle at risk.

      The viaduct is not the only problem. Like in California, rapid urbanization during quiet periods between quakes has created a sense of complacency. But the older areas of Seattle are full of unreinforced masonry and other building types that are particularly vulnerable. California has had a succession of medium-sized quakes in the last forty years, the combination of which has led them to retrofit similarly dangerous housing and transportation infrastructure beyond what we’ve done here. Certainly retrofits are subject to cost-benefit analysis and should preserve the feel of the neighborhood, improving it where possible. But we are way behind, and the viaduct is just the start.

    3. Washington history is since 1854 (I think?), since that’s when it was named a territory. The geologic history of the region certainly didn’t start then. In 1700 there was a quake estimated to have been ca. 9.0 on the Richter Scale – along the lines of Chile or stronger. Those quakes originate on the Cascadia Subduction Zone, are similar geologically to the one that produced the Indian Ocean Tsunami, and happen on a 300-500 year cycle as stress builds along the subduction zone.

      Additionally, there is certainly an active fault in the Seattle Fault, which is right around like if you drew Royal Brougham all the way from Bainbridge to Sammamish.

      Seismology has in the last twenty years gone away from statistical predctions of earthquakes; i.e., based on past ones. We can now understand individual faults a lot better than just the number and magnitudes of earthquakes they have historically produced.

    4. MattG, the Nisqually earthquake may have had a large magnitude, but because it was so deep and far away it wasn’t that destructive in Seattle. Still, had it been shallower, or had the shaking continued for a few seconds longer, sections of the Viaduct and seawall may have failed back in 2001.

      But the Nisqually earthquake still doesn’t represent the most serious seismic threat to the Seattle area. The Seattle fault, which lies approximately under I-90, last moved ~1100 years ago. If this fault moves again, it could potentially kill 1,600 people and cost $33 billion in damage and economic losses (EERI), as well as pancaking the Viaduct. This kind of earthquake has a non-trivial chance of occurring in the next 10 years.

  4. I wonder if putting the video out will have the same effect on others as it did on me – I’m just never driving on the viaduct again. Eek!

  5. To be intellectually consistent, anyone calling for the Viaduct to be torn down immediately should be demanding the speed limit on all roads and interstates should be 30 miles an hour since we know that would save 1000’s of lives each year.

      1. while this is true, it doesn’t have to be.

        if we planned cities in a pedestrian friendly manner, with lots of readily available, comfortable transit, we could have both safety and convenience.

    1. Frankly, Robert, I’d love that. It would be a great way to promote intercity rail travel again, and it would have little impact on in-town trips. It would also help stop sprawl.

  6. In Oakland, not in Berkeley, but the collapse of a double deck freeway is fairly horrific.

  7. Good commentary Mr. Duke, I must agree with the letter from the 5 stake holders. Delaying removal is irresponsible. The animation is just a guess; predicting earthquake damage is not a science yet. Remember there was no seawall next to the Oakland viaduct and the engineering and style of Oakland’s Nimitz Freeway and the Seattle Viaduct are almost identical.

    1. No, Tom, the Nimitz freeway and the AW Viaduct may look similar but they are not identical in design. There are significant differences in the way the columns are attached to the decks — a weaker design in Oakland lead to the collapse of that freeway. All this was covered in the media some time after the Loma Prieta earthquake.

      The AWV has a better design, but as the video notes, not one that’s immune from destruction.

      Personally, I think it’s irresponsible to not shut the thing down immediately. I know I won’t drive it again, except as a last resort and with prayer.

  8. Nooooo! Don’t take down the Viaduct yet! I still need it as cover while walking in this rainy winter. :-p

  9. I felt sick just looking at the first two minutes of that video and shut it off at that point. Interestingly, it looks like the surface streets might fare just as badly in an earthquake as the viaduct. Has a comparable video been made of what might happen to drivers in a tunnel under 1st or 2nd avenue in the event of an earthquake. Both the downtown BNSF tunnel and the Downtown Transit Tunnel appear not have been negatively impacted by the Nisqually quake that I am aware of.

    1. One thing that helps in a lot of tunnels is the circular or arched structure. (Not necessarily a viaduct tunnel only, but a Link tunnel, heavy rail tunnel, sewage tunnel, etc.) Plus you have a huge amount of material that it’s built in and restricts the amount by which its movement could possbily be amplified, unlike an elevated structure, which can sway at the top more than the ground movement below.

      1. Of course building a double deck tunnel underground still has the potential of the upper deck or pieces of the upper deck falling on those below. This is no longer an arched ceiling. The original dual bore plan also entails less risk because it uses existing technology. Hard to say if one large tunnel has more or less impact on soils and the above ground stuctures. It goes deeper but has a narrower foot print. Maybe they should do an environmental impact statement before proceeding with a single alternative?

      2. Well there’s a thought. It would also be nice to have WSDOT comply with the laws requiring an EIS before proceeding with the preferred option.

  10. Being from West Seattle and having to use the viaduct a lot, and mostly using the street system (via bicycle) is always a scary proposition and I think about an earthquake frequently. The traffic in that video is very light and there are no pedestrians, cyclists, cabs, buses, and other road users (parked cars anyone?) anywhere nor is it occuring during rush hour or in the dark. If anything that is video light.

    Sure, there may not be as big of earthquake that the video depicts, but even a smaller one could easily damage the already earthquake damaged viaduct further causing it to be shut down as too unstable. The seawall could also collapse in a smaller earthquake, which may not necessarily kill anyone but it could damage the waterfront structures and street grid irreparably.

    The whole thing should have been taken care of years ago. Years ago! 2001! Now look where we are, still arguing.

  11. The question to ask is which viaduct replacement option eliminates the threat of catastrophic collapse soonest. The answer there is the Surface/I-5/Transit option.

    Advantage: Mike McGinn.

    Which tunnel option, Deep-bore or 4-lane cut-n-cover, reduces the threat sooner? The critical factor is the Seawall. The cut-n-cover is a slow-progressing construction process for rebuilding the Seawall. The Deep-bore would most likely finish the seawall first.

    However, a ‘box’ tunnel on the Waterfront would strengthen the soils and prevent major liquification. The cut-n-cover is built in 2-block segments. Each completed segment has less threat of soil liquification.

    So, in addition to the 4-lane Cut-n-cover handling traffic much better than the Deep-bore, it also acts as a major soil stabilizer.

    Advantage: Mike McGinn

      1. I’m not being argumentative, I just don’t understand why you’re attributing a 4-lane cut-and-cover tunnel to Mike McGinn.

    1. These are all questions that we can’t answer without going through the EIS process. You left out at least one other option which is to seismically retrofit the existing structure.

      1. That’s right, Bernie. Toss out the “Process” card. The existing structure is seismically unsound, period, end of story. The replacement alternatives are Surface/I-5/Transit, 4-lane Cut-n-cover, Deep-bore. Which one decommissions the AWV soonest? Which one handles traffic best? If you have an opinion in that regard, answer accordingly.

      2. There’s little money (comparatively) to firms like CH2M Hill and PB to doing a seismic retro fit so of course they don’t promote that option. It also has zero sex appeal to politicians that want to promise a “reclaimed” waterfront and a trolley in every stocking. But that’s certainly the first option I’d look at to compare cost and viability. The State doesn’t have the funding to build the tunnel; it’s not fully funded despite cutting the estimates, cutting back reserves on the riskiest engineering alternative and pushing cost overruns onto the City of Seattle. The State also hasn’t figured out a way to pay for the SR-520 corridor rebuild which it intends to do simultaneously. So, as long as we’re tossing out the process card I’d vote for retrofit.

        I’m not against the tunnel because it promotes automobile use. I see the lack of exits to downtown as a feature, not a problem. But I don’t buy into this “sunny beaches” idea of what the waterfront will look like. I see six to eight lanes of traffic, no parking, less ability to bike and much harder for pedestrians to cross. It’ll be gorgeous only for those that have views from upper story windows.

        If the funding is found for a tunnel, from what little we’ve been told so far I strongly prefer the 6th avenue Seattle Tube idea that was given the bums rush. If the costs are comparable you get a lot more bang for the buck.

        And for the record I don’t believe tearing it down and doing nothing or just adding transit is a viable option.

    2. What are you talking about?

      The Deep-bore would most likely finish the seawall first.

      Which is what Mallahan has championed as not just the “arrived” solution but the best solution. Yet you have no “advantage Mallahan”.

      As Zed pointed out, McGinn is anti tunnel and doesn’t support a cut and cover option. In fact he’s expressed more support for the DB alternative if there is a tunnel at all.

      And, absent an EIS how is it you know the seawall is the dominant factor in public safety. I’ve only ever heard it described as essential for preserving an artificial waterfront and for the most part no longer relevant in terms of shipping commerce. I’ve heard no claims that the demise of the seawall would result in catastrophic failure and loss of human life in the event of an earthquake.

      1. The seawall is part of the structural system that contains the soil supporting the Viaduct and Alaskan Way. If the seawall fails, lateral spreading and liquefaction will undermine the columns and some sections of the Viaduct’s decks will collapse. There is also the possibility that the movement of the seawall will undermine the piles which support buildings like the ferry terminal or the aquarium. Plus, broken gas lines and broken power lines (both under the Viaduct) will cause fires in many places along the waterfront.

        But don’t take my word for it, listen to what the Army Corps of Engineers have to say:

        “At this time, additional information was collected regarding the condition of the Alaskan Way Seawall. The information showed that the Seawall was also seismically vulnerable and in a state of disrepair. The information also showed that the structural integrity of the Viaduct is dependent on the Seawall.”

  12. By any chance, is this the seawall Hucthinson accuses Constantine of taking money to repair?

  13. “Remember: subjecting new highway projects to due process and environmental review: reckless disregard for people’s lives. Leaving a brittle viaduct up to make sure auto trips into downtown are convenient: good transportation planning!”

    Amen to that. There’s no sense of urgency with the McGinn crowd, just that they get their way no matter what the costs.

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