McGinn’s Consultant: “Worst Geologic Setting I’ve Ever Seen”

Photo by Zach

Yesterday Mayor McGinn held a press briefing with Thom Neff, a Strategic Infrastructure Management Consultant that the Mayor had retained to complete a risk analysis on the likelihood of on-budget, on-time completion of the Alaskan Way Viaduct replacement tunnel. Neff, with a 40-year vocational history managing large tunneling projects (including Boston’s Central Artery, the “Big Dig”), offered a cautiously pessimistic assessment of the project.  Noting that the tunnel represented technology “at or beyond precedent” in the “worst geologic environment [he’d] ever seen,” Neff said that the project presents a substantial risk of exceeding budget and a moderate risk of not being completed at all.  Among the geological anomalies, historical glaciation was so extensive that there is “residual lateral stress at depth” that  “exceeds the vertical pressure.”

Everyone expected our anti-tunnel Mayor’s hand-picked consultant to say such things, but Neff was impressive and decidedly apolitical, stressing that, “I love tunnels, that’s what I do.  But some tunnels shouldn’t be built.”

More after the jump.

Neff made several administrative suggestions that would increase accountability and incentivize safety, including:

  • The builder of the ($80m) tunnel-boring machine having to share financial risk.
  • Real-time construction monitoring data being handled by WSDOT rather than the contractor, lest we get a situation in which “the fox is watching the chicken coop”.

There is not much new here, and there are already a dozen articles online about this, but I’ll make a cautious editorial point (entirely my own) relating to transit advocacy.  Precedent-busting technology is appropriate for projects emanating from exceptionally high travel demand, but the AWV clearly does not represent such demand. Accordingly, we should be wary of pushing too hard with risk-aversion rhetoric when our primary reasons for opposing the tunnel relate not to risk but to utility.  If we appear too technophobic or risk-averse, only to call for innovative transit tunneling later, we risk accusations of disingenuousness and hypocrisy that limit our political effectiveness.  If in future we want new right-of-way for high-speed rail, a 2nd Avenue subway, etc…we need to resist this sort of situational technophobia today.  Isn’t it better to be authentically ideological than inauthentically risk-averse?

Comments

  1. Mike Skehan says

    I have to wonder what our grand children will be debating in 2040. Deep bore tunnels for both cars, trucks and transit may be the least of their worries instead of how to heat the home or grow the food needed, as resources and climate undergo significant change.
    Looking at Google maps shows an impressive amount of surface land area devoted to transportation – parking spaces, garages, roads, airports and rail. I suspect our grandkids will start picking all this low lying fruit sooner than we think.

    • Stephen says

      I doubt that the topics of debate will change much in only 30 years. As for your concern about energy or food supplies, I doubt that the debates about these will be any louder in 30 years than they are now. The biggest problem is probably that if peak oil is real, we will have to convert to electric vehicles, but this is already a solved problem so-to-speak technologically (we have the ability to create electric vehicles, we just don’t due to low demand, but if oil became increasingly expensive that’s easy to rectify).

      No, I’m sure that in 2040 they’ll be debating whether or not we should expand light rail to Issaquah, and whether or not we should complete the North Link to Everett. Also, if we’re lucky, they’ll even be debating if we should purchase the necessary ROW to support high-speed-rail from Portland to Vancouver.

      • Mike Orr says

        Link to Everett and Tacoma will probably be in ST3, and if not then ST4 or 5. That would put it opening between 2030 and 2040. (Assuming there are no major construction problems with North Link or East Link.)

        Issaquah Link would probably be later, maybe ST4 or ST5, because there have been no concrete proposals on where it would go. Should it go to South Bellevue and serve Seattle-bound people best? Or should it go to BTC and serve Eastside-bound people, forcing Seattle-bound people to backtrack? Should it continue north toward Kirkland and Lynnwood? Or go to Seattle via 520 or a new transit bridge?

    • Bernie says

      In 2040 the debate will be about replacing the I-90 sinking bridge(s). That’s going to make the $6B SR-520 corridor project look like chump change. At least the tolling debate will be a done deal by then. The debate will be about tearing out Link before the bridge is removed so that center roadway can be used to generate the toll revenue required to replace the span.

      • Mike Orr says

        If they really need money from train riders to replace the bridge, they can build a toll into the rail fare for cross-bridge trips.

  2. lazarus says

    I would concur with your comments about risk.

    Yes, there is risk with the DBT, but then there is always some level of risk with any tunnel. The level of risk with the DBT just isn’t that unusual for a tunnel and certainly isn’t unprecedented. And the risk with the DBT would manifest itself as cost/overrun risk and not technical feasibility risk anyhow. Nobody is saying the DBT is so risky as to be technically unfeasible.

    Additionally, those of us that are proponents of a 2nd Ave LR tunnel should be careful how much we criticize the DBT for risk. The DBT goes under the water table which increases risk somewhat, but the 2nd Ave LR tunnel would be twin bore with mined cross-overs and cut and cover stations, and both of those would increase risk too.

    • Grahm says

      Lazarus, to say the level of risk with the DBT isn’t that unusual for a tunnel is pretty contradictory to the Mayor’s consultant. “worst geologic environment [he’d] ever seen,” screams unusual.

      I would expect a high level of scrutiny regarding any tunnel in the region, whether for transit, auto, or other purposes. I don’t believe risk-aversion should be the sticking point of pro-transit DBT opposition. Nor do I think glossing over the level of risk on this project so as to not seem hypocritical on a future transit tunnel is a wise move. Personally, I would oppose a transit only DBT based on the risk assesments we have seen over the past weeks.

      • BurienBen says

        “’worst geologic environment [he’d] ever seen,’ screams unusual.”

        Grahm, what doesn’t scream unusual is that it was said by someone paid by the mayor, who is against the tunnel.

        (Now not talking to Grahm) Anyone can find an expert that, if paid the right amount, will come to a conclusion that you want. It is done everyday in courtrooms across America. I don’t take too much from someone who is paid by a side and their conclusion is in agreement with whom they have been paid by. Now, if he had come to the opposite conclusion, I would tend to believe him.

      • lazarus says

        I agree 100%. This consultant was hired by the mayor precisely to back up the mayor’s position. Tunnel proponents could just as well hire their own “handpicked” consultants to support their position.

        This “study” cost $40K which the mayor seemed to have no qualms about spending. Personally, I’d much rather have had him spend that $40K on something useful like funding part of the Aloha Ext SC study phase.

      • Adam B. Parast says

        You’re complaining about a 40K study for a project that will cost over 4 billion dollars?

      • lazarus says

        I’m saying I’d rather see money spent to actually accomplish something instead of seeing money spent purely to stop something from being accomplished. And this is not the first time the mayor has spent city money trying to stop the tunnel. Eventually it all adds up to a rather substantial waste of city funds.

        And the point of funding the Aloha Ext Study Phase is that you can potentially leverage a small amount of study phase funding into a larger amount of construction phase funding (grants, Fed funding, etc). We are missing a golden opportunity to move forward.

        Besides, the funding for the DBT is not city funding — it is State funding. If it doesn’t get spent on the DBT then it will get spent on some suburban freeway somewhere else (N-S Freeway in Spokane???).

        It’s not our money, the mayor’s $40K is.

      • Tony the Economist says

        40k is about 5% of the cost of the preliminary engineering for the Aloha extension and less than 0.2% of the estimated cost of construction. 40k would be about 1.3% of the cost of purchasing a single streetcar vehicle, and would be enough to cover the marginal operating costs associated with the extension for about 3 weeks.

        $40,000 may seem like a lot of money to you or me, but in the context of transportation systems, it doesn’t even amount to a rounding error. Getting upset over this expenditure is a waste of time.

      • Grahm says

        Ben, I am well aware of who is paying Mr. Neff. What I am not aware of is how anyone can read the above article and conclude that the DBT isn’t unusual. While the quote is undeniably loaded politically toward the mayors position, the point is that soil in which the DBT will be constructed introduces significant risk.

      • lazarus says

        The risk due to soils is not significantly worse than what ST will be dealing with when it builds U-Link, or significantly worse than what ST has already dealt with building Central Link.

      • Nathanael says

        “The risk due to soils is not significantly worse than what ST will be dealing with when it builds U-Link, or significantly worse than what ST has already dealt with building Central Link.”

        Yes, it is. It is much worse.

        This tunnel is going through loose 19th-century (mostly) fill. Among other things. Not present in previous bores.

        Also of note: ST actually *removed a station* from the U-Link route due to geological risk, so that they could route the tunnel away from the risk. The comparable thing to do with this tunnel would be to move it to a different location entirely.

        Which, as others have noted, makes sense. If you really really want a road tunnel from Ballard to South Seattle, the Waterfront is the worst geological location for it. Put it somewhere else.

      • Nathanael says

        Neff thought the Big Dig was manageable. And he’s negative on this tunnel.

        Of course Neff may be overreacting after being burned by the Big Dig. But if not… think about who’s saying this a little more carefully than just “McGinn’s paying him”.

      • Dave says

        Consultants often come up with the results that promote the agenda of the person who is paying them. I would have been shocked if this consultant had said anything other than it being a complete disaster waiting to happen.

      • Zed says

        Actually he was very careful in the way he stated his (educated) opinion. He never once made a value judgment on whether the tunnel should or should not be built. All he did was give his professional opinion on the constructability of the project and what the magnitude of the risks are. He specifically said that it is someone else’s job, i.e. the public, to decide if the benefits are worth the cost.

      • Adam B. Parast says

        The thing about consultants, real engineering consultants, is their credibility comes from being impartial and straight forward. If they lose this they lose their ability to win contracts.

  3. groan says

    Don’t worry folks, the new supersized viaduct is in our future. It may be shorter but it will be wider

    • lazarus says

      The one thing we surely won’t get is a viaduct (new or retro-fitted). There will be no viaduct on the central waterfront (DBT or no DBT).

      We’ve learned to much too much to repeat the mistakes of the 50’s.

      • lightning says

        Yet why do I [continue to] have this sinking feeling (semi-pun intended) that in the end of this sorry and almost laughable process that’s exactly what we WILL get–a new viaduct. My worst nightmare come true. It looks more and more likely that there won’t be a tunnel–Seattle doesn’t have the stomach for it. Others cities would have the thing half-built by now.

      • Steve says

        Other cities would not have the thing half-built by now. Oakland and SF still haven’t finished replacing the Bay Bridge, which had it OMG-it’s-about-to-fall-any-moment-now Earthquake in 1989. New York has taken 80 years to build the Second Avenue Subway. Boston’s been trying to get light rail to Somerville for 15+ years (part of the Big Dig mitigation) and just delayed it again.

        Big projects take a long time everywhere.

      • Carl says

        How many miles of mag-lev does Shanghai have now?

        One underused line to the airport, which ends on the outskirts of town.

        Not building any more mag-lev in China.

      • groan says

        “The extension to Hangzhou was finally approved in March 2010, with construction to start in 2010 [5]. The new link will be 199.5 km (124.0 mi) long, 24 km (15 mi) longer than the original plan. The top speed is expected to be 450 km/h (280 mph) but limited to 200 km/h (120 mph) in built-up areas.”

        I guess not

      • Erik G. says

        But you forget that Red China has tons of hard currency owing to its ability to enslave workers and pay them a pittance, and with the full collaboration from Investment bankers like Willard “Mitt” Romney who buy up businesses in the country and then move the production overseas to China where worker safety is non-existent, and new labor from the rural east arrives every day.

  4. archie says

    I think the biggest point here and the one McGinn is trying to drive home, is that you have a riskier than average project with a funding structure that doesn’t properly address that risk. (e.g., unstable language for dealing with cost overruns and contractors not having to include enough risk in their bid prices)

    • archie says

      And despite one’s stance on this tunnel or any future risky transit project, a sound financial structure should be demanded by both critics and proponents of the project.

    • Adam B. Parast says

      Yeah I agree. There is two different points. One to say there is unprecedented risk, the other to say the structure to pay in case of overrun is not sound.

  5. Erik G. says

    Even Herb Caen, beloved columnist for the San Francisco Chronicle, opposed the freeway removal. As it started going through commissions, Caen wrote. “Once again, there is ‘serious talk’ about tearing down the Embarcadero Freeway, an even worse idea than building it.” He continued to write against the freeway removal, and in his column of June 2, 1986, immediately before the election, he wrote, “It no longer blocks views, it provides some exciting ones. And while the drawings of a tree lined boulevard that would replace a torn-down freeway are alluring, so were the renderings of the New & Improved Market St. and look how that doggy-bow-wow turned out.”

    http://www.preservenet.com/freeways/FreewaysEmbarcadero.html

    • MarkS says

      The Embarcadaro again? That was a spur route not a throughput like the AWV.

      You’re comparing apples and oranges.

      • Carl says

        More than 50% of AWV originates or terminates in the city at Western, Marion/Seneca and First Ave. It’s a myth that this is a through-route – what does it connect to? Aurora Ave with traffic lights? East Marginal?

        What’s ridiculous is spending so much money for an estimate of 44,000 vehicles using the DBT. Tear down the viadcut but don’t build a new tunnel or viaduct.

      • Eric L says

        It’s through in that most of the traffic is going all the way through downtown, and not into it. But very little of the traffic is going through Seattle.

      • Tony the Economist says

        Yes, and if we were going to spend $4 billion to improve or maintain throughput in downtown, we should spend that money improving I-5, which is the actual through route. As Carl said, 99 is primarily local. What is terribly frustrating is that people seem to have forgotten that the alternative McGinn supports is not called surface-transit; it’s called surface-transit-I5. There were hundreds of millions worth of improvements to I-5 in that package that we cannot afford to pursue now because we are spending it on building a through-tunnel for a local route while the artery that everyone cares about (I-5) continues to be neglected.

      • Zach Shaner says

        At least with I-5 we’d have the protections of federal funding. Massachusetts never would have done the Big Dig if it had been “MA 93″ instead of I-93.

      • Eric L says

        Actually, this is what I don’t like about surface/I-5. The thing is “sprawl” is often given as a reason to oppose the viaduct, and while it’s true of freeways in general, the viaduct really doesn’t cause sprawl, unless you consider West Seattle or Phinney Ridge to be sprawl. Here we have a highway that’s quite convenient for residents of western neighborhoods making in-city trips that is not convenient for residents of far-flung suburbs. Why are we talking about replacing it with lanes on I-5, which are as easily filled by people making much longer trips (and really aren’t convenient for residents of Ballard)? Why make Ballard less accessible while making Lynnwood more accessible?

      • Mike says

        “More than 50% of AWV originates or terminates in the city at Western, Marion/Seneca and First Ave. It’s a myth that this is a through-route”

        “As Carl said, 99 is primarily local.”

        Um, half is not “primarily”. It’s 50% And many would argue that Western is not “local”.

      • Adam B. Parast says

        I completely agree. This is where *most* of the freight traffic is and this project will improve regional mobility more than 99 will.

      • Erik G. says

        No, the Embarcadero viaduct was part of the route of US 101 through the city, and was supposed to be extended all the way to the Golden Gate bridge.

  6. striatic says

    When I first heard the risk-threat argument on The Stranger I thought it was fear mongering, but “largest tunnel bore ever attempted” plus “directly under downtown” plus “along a geologically unstable waterfront area” puts up some red flags.

    With potential future transit infrastructure you can just say “it isn’t the largest bore ever attempted”, “it isn’t directly under downtown” and “it isn’t in an unstable area”. so I don’t think any of this really effects the future of mass transit development.

    If it really is risky, then it really is risky, future abstract hypothetical political considerations be damned. I’m not an engineer, but the more i really think about the DBT, the more the “it’s risky” argument makes sense. Not with visions of the Federal Building collapsing into a giant sinkhole, but with all the unexpected problems involved in mitigating unexpected dangers driving up the time and expense.

    • says

      Except that it has been argued that Ballard or West Seattle light rail to downtown would require an additional transit tunnel, since the existing tunnel under 3rd is already scheduled to be full with North/East Link trains coming on board, decreased headways and four-car trains. A 2nd avenue transit tunnel would be directly under downtown, and in the same unstable area; just not as a deep nor as huge.

      • Zed says

        Actually a new transit tunnel would likely be under 5th Avenue, its already been studied by Sound Transit. A transit tunnel there would be just under the surface, much like the existing transit tunnel, and wouldn’t be under building foundations, under the water table, and wouldn’t be built through the garbage tip that Pioneer Square was built on top of. There is a world of difference between the type of tunnel they would build for transit and this double-wide deep bored tunnel they’re proposing for SR99.

      • says

        Sure, but I don’t know that you’ll have enough mindshare to make specific arguments. When people say, “You transit nuts didn’t want a car tunnel but now you want a train tunnel,” how much time will you have to be arguing the different in soil types, the vertical and horizontal distances from foundations and bodies of water?

        It feels like this argument is really, “the tunnel is financially risky, lets not get caught with our pants down” and not “the tunnel is going to kill us all.” Although, my imagination digs a skyscraper falling into a sinkhole caused by a five-story tunnel drilled deep under the city.

        I was at the meeting that where the DPD presented the “Green Street” near the North portal if the SR99 Tunnel that became Josh Cohen’s recent Publicola article. What was interesting was how unsure of the traffic numbers coming out of the north portal DPD was, coming from WashDOT.

        I’m still in the boat that thinks Seattle is changing and we’re tossing billions of dollars at a transportation project to please people who still believe their industries won’t.

      • Martin H. Duke says

        I agree that the optics of this distinction are much, much worse than the merits.

        Of course, by the time we debate a second transit tunnel, maybe all the veterans of the DBT argument will be dead. :-)

      • Tony the Economist says

        Here’s the real rub: precisely because it is difficult to distinguish politically between one tunnel project and another, if we proceed with DBT and the nightmare scenario does unfold, you can kiss your 5th Ave transit tunnel, and every other potential transit tunnel goodbye.

      • Zach Shaner says

        Tony, thank you, that was my whole point. Not that the DBT has much to do with future transit tunneling at all, but that the public and/or major media won’t be able to distinguish between them.

      • Nathanael says

        ‘It feels like this argument is really, “the tunnel is financially risky, lets not get caught with our pants down”’

        That’s a pretty good argument, isn’t it? If they’d listened to that argument when Massachusetts went insane building the Big Dig, they wouldn’t have built it.

      • Bernie says

        this double-wide deep bored tunnel they’re proposing for SR99.

        Or in Seattle speak, a “Double Tall with a Cherry St. on top.” :=

      • Mike says

        “Actually a new transit tunnel would likely be under 5th Avenue, its already been studied by Sound Transit”

        Link please. thx!

      • Geoff says

        That article is 8 years old and the purpose of the study is different. It was just on this blog recently that any new transit tunnel downtown would likely end up under 2nd Avenue so that it could serve Ballard/QA to the north and Sodo/West Seattle to the south.

  7. Bernie says

    the “worst geologic environment [he’d] ever seen,”

    I’m thinking back to the 5th Ave Seattle Tube idea which was dismissed out of hand because “the fix” was already in. Before deciding on a location for a $2B hole in the ground a few million to actually drill core samples and do traffic analysis might have been a good idea.

    • Zed says

      “Before deciding on a location for a $2B hole in the ground a few million to actually drill core samples and do traffic analysis might have been a good idea.”

      That’s what I always thought too. It’s not like this “solution” came from an actual thorough study of alternatives, it came from the Discovery Institute who drew a line on the map and then paid a consultant to tell them that it could be built. Then they passed it on to WSDOT and it suddenly became the preferred alternative. The hole thing always seemed a little fishy to me. Why are they in such a rush to make a decision before a proper EIS is even done?

  8. Mike Orr says

    Could a transit tunnel on 2nd or 5th be cut and cover? I realize people hate cut and cover due to the street disruption during construction, but it seems like it would be much less risky than a bored tunnel.

    • Zach Shaner says

      2nd Avenue would be the easiest cut-and-cover downtown. There’s hardly anything on 2nd today aside from some great architecture and oodles of office space. It functions almost as an alley for 1st and 3rd.

      5th is also quite possible, but it’s narrower and c-n-c construction would adversely impact a significant stretch of the retail core. Plus it would be quite odd if a Ballard-West Seattle line, for instance, were built to the east of the current DSTT, even if it’s only two blocks. A 5th Ave tunnel would have to cross the current tunnel at some point.

      • Eric L says

        5th seems like a good idea to me. Slightly less redundant, better transfers at Westlake and King Street, and only three blocks further to get there. 5th also has less traffic than 2nd. Provided the crossings aren’t prohibitively expensive. Perhaps the old battery street tunnel could be used to jog to the west in Belltown?

    • lazarus says

      Good gawd, have we become so risk-adverse that we can’t even contemplate doing in 2010 what we already did successfully in 1990?

      The DSTT was built without using cut-and-cover back in the late 1980’s. If I remember right they had a little stripe painted on 3rd that told the pedestrians above how far the tunnel had progressed below. If we could do it successfully in the ‘80’s, then surely we can do it again in the 2010’s with our better technology and better engineering.

      Note: I believe the DSTT was built using Shield Excavation (TBV), except for the stations and the Westlake to Convention Place Station segment which was cut-and-cover. It was the cut-and-cover portions that people found so objectionable and eventually led (in part) to CAP which had the affect of increasing urban sprawl.

      • Mike Orr says

        Wasn’t 3rd Avenue closed for construction or am I remembering wrong? Of course, I don’t remember the Capitol Hill or Queen Anne buses being moved off third, so it must have been passable.

      • striatic says

        isn’t the DSTT smaller diameter and entirely above the water table, presumably in denser soil?

      • Bernie says

        I don’t think the issue with the DBT is so much the geology of what the tunnel it’s self is going through as it is about the ground above the tunnel than all the buildings along the waterfront (that fall down on their own) are built on. Vibration, changes in the water table (different than sea level), possible voids or sand shafts, etc. all make these buildings even more unstable. If one of these events happens while tunneling is going on it may or may not have been a contribution factor and likely impossible to determine. But man will there be one huge legal brew-ha-ha. I can see the City claiming it was tunnel construction, the State claiming it was sea wall replacement and the construction company claiming “act of God.” Send lawyers, guns and money.

      • Nathanael says

        I think you’re basically right. The buildings in the area are all built on loose fill. Any form of tunnelling under (or through) that is extremely risky. That’s why the original proposal was to build a cut-and-cover tunnel *as part of* the replacement seawall, which would be something like London’s Thames Embankment — that would be managable-risk.

    • Zed says

      Shallow, average diameter bored tunnels aren’t risky at all, and are usually easier than cut-and-cover. Extremely deep mega-tunnels are a different story.

  9. Mike Skehan says

    Speaking of risk, I remember reading years ago about the seismic risk on the I-5 elevated, double deck, and ship canal crossing from Convention Center to the U-dist. All of that was built to decades old standards. I know of some seismic strengthening over the years, but finding the risk assessment on WSDOT’s web site is hopeless.
    Loosing I-5, and having 1/2 the capacity on the new DBT over the AWV is kinda scary.

Trackbacks



You may want to read our comment policy.