In Seattle, a Sinking Feeling About a Troubled Tunnel

http://www.nytimes.com/2014/12/10/us/in-seattle-a-sinking-feeling-about-a-troubled-tunnel.html

by wallflower • 12 years ago

55 43 12 years ago

ChuckMcM2• 12 years ago

Tunnel Boring machines (TBMs) fascinate me. A machine that is part excavator, part factory, part structural support. And generally custom made for every job, wicked expensive, and by all accounts very high maintenance. Seemingly only "slightly" better than just digging the hole the old fashioned way with sand hogs and trucks.

Given their nature, I have always wondered whether or not it would be possible to use the excavating end as a 'portal' to manually excavate in the case of breakdown, such that you could get to the "outside" of a damaged TBM but clearly that isn't a design feature (the Swiss needed to get to theirs as well as I recall on their tunnel project through the Alps. That we got a pair under the English channel seems amazing.

adamnemecek• 12 years ago

I've posted this before but this video showing the operation of the machine is really interesting

https://www.youtube.com/watch?v=Dk-8Q42NCSQ

tehaugmenter2• 12 years ago

That is really cool! Thanks!

grecy• 12 years ago

There are some awesome documentaries on the digging of the chunnel, giving details of how they guided to two TBMs (they used lasers pointed backwards to extrapolate direction), how close the two were in alignment when they met up in the middle (I won't spoil it), the Friendly rivalry between the two digging teams to see who could get to the mid-point first, and other challenges they faced when they discovered the structures in the earth under the water were a lot more complicated than they originally thought.

https://www.youtube.com/results?search_query=chunnel+digging...

RyJones4• 12 years ago

I looked into buying a used 24" TBM, turns out it's quite affordable to buy one, use it for a project, and sell it. It can be much cheaper than trenching.

Project didn't move forward. Pity.

g8oz• 12 years ago

How much was it?

ChuckMcM2• 12 years ago

I didn't realize there was a market for small TBMs (or horizontal drills as they seem to be called) but the Robbins company [1] has some awesome data on that. You can get 250mm - 5000mm ones off Alibaba for $120,000 - $600,000. Amazing less than the price of a house :-).

[1] http://www.therobbinscompany.com/en/our-products/

jallmann• 12 years ago

Yep, fascinating stuff. Here's their plan for fixing the machine: http://www.wsdot.wa.gov/Projects/Viaduct/Media/Default/Docum...

Shivetya• 12 years ago

Guess they never meet too expensive of a government project up there, Seattle was spending 625 million per mile on another tunnel (3.1 miles of it) for light rail extension.

Insanity all around.

pyrocat3• 12 years ago

The light rail extension is a much more cost effective, useful, and popular project than this debacle of a tunnel.

tehaugmenter2• 12 years ago

It's also 12 stories deep in the ground.[1] I was also looking for the other dimensions for the tunnel. It's just crazy to think about digging holes like that. Just like the Channel Tunnel along the English Channel. Insanity is just the name of the game when it comes to Tunneling.

[1] http://www.npr.org/2014/12/10/369777033/bertha-the-giant-bor...

koenigdavidmj• 12 years ago

Sound Transit's project, an extension of the Central Link tunnel north to the UW, is ahead of schedule and under budget. Most of us in the city are happy to give them more money since they succeed at their job.

hga6• 12 years ago

"That was when the machine’s bearings became clogged with grit after digging only about 10 percent of a two-mile highway tunnel beneath downtown."

Perhaps. Perhaps more significant is that (all this from memory when I did some research after learning about this Charlie Foxtrot) the machine failed 3 days after it chewed through the steel casing of well sunk and then left there by the same state government org that's running the whole project.

Almost needless to say, they didn't tell anyone about this minor detail for a month. And while no one was talking when I checked, it's obviously very questionable this will be covered under Hitachi's warranty coverage.

Another minor detail is that that state org, their transportation department or whatever, has a wonderful financial setup for this project. Well, for them, anyway. They're paying a fixed amount, and the city will have to cover any overages. Which at this point look to be substantial, I think they'll have blown through the project's ~$48 million reserve by now.

Oh, and that earthquake damaged viaduct? Estimates are that if the tunneling or other activities like this rescue cause it to drop by 2 inches (1 more than the hopefully local drop reported in this article), they'll have to close it.

pyrocat3• 12 years ago

A downright prescient 2010 article from Seattle's local alternative newspaper http://www.thestranger.com/seattle/what-could-possibly-go-wr...

hga6• 12 years ago

Fairly so, and particularly good in introducing the "who pays for overruns?" whammy in the 4th paragraph after minimally setting the stage.

"While construction unions are backing this project, labor disputes could also get in the way."

Some union dispute indeed delayed the start of the tunnel by a month.

On the other hand many of the cited possible problems might have been amenable to fixing in place, e.g. the cutters in the front are replaceable. The terrible problem now is that its main bearing is messed up (forget if it's just one or more seals, or worse, or even if they really know yet), requiring this major excavation to get to it and then surgery. If the problem wasn't, or wasn't uniquely caused by that steel well casing, it could get broken again ... it's only done 10% or so of the length.

And, yeah, the traffic projections aren't great. As I remember, no matter how people go "wow!" about the size of the tunnel, the capacity of it will be quite a bit less than the viaduct. Then there are all the other factors that can make it less desirable.

timr2• 12 years ago

That's not especially meaningful -- if there's a hipster-reactionary position to be taken on construction projects, the Stranger will take it.

The Stranger has a long history of fighting losing fights to keep things more-or-less the same -- unless the alternative is trendy and/or guaranteed not to impact Capitol Hill. For example, they'd prefer that the viaduct be replaced with a "surface boulevard" that has a fraction of the throughput, thus all but guaranteeing decades of gridlock in downtown Seattle (which they like because it "discourages driving", because they heard that San Francisco did it...and most importantly, because it doesn't affect their lives either way).

Meanwhile, they complain constantly about light rail on the hill, but they campaigned heavily for the monorail-to-nowhere. Why? Because it was a monorail (cool!), and the construction wouldn't affect their favorite neighborhood (even better!)

Point being, it's not difficult to pull an article from the Stranger predicting doom for a major urban planning initiative. That's practically their stock in trade.

larubbio• 12 years ago

The steel casing was in the survey provided to the contractor as part of the contract documents.

http://seattletimes.com/html/localnews/2022757238_berthapipe...

hga6• 12 years ago

The contractor and others assumed the casing had been removed.

We all know about assumptions, but this shouldn't be entirely blamed on the contractor, especially since WSDOT is ultimately responsible for the project.

There's clearly a serious if not fatal problem with leadership of the whole project, which as I noted has very bad incentives that are aligned with allowing problems.

In this case, there should have been someone obsessing on the path of the tunnel. And then the boring crew, its supervisors etc. should not have, after hitting the casing (which cased the top part to jump many feet into the air), blithely continued boring until the machine failed hard (that could have turned something relatively fixable into the disaster they have now).

I'm unimpressed.

barsonme• 12 years ago

WSDOT is so incompetent. It's absolutely infuriating, and definitely not helping the political divide between eastern and western Washington.

The very urban portions of the coastal areas pay most of the taxes, while the rest of the rural parts pay a much smaller portion. Unfortunately, the rural parts (basically anything not directly within x miles of the coast) see this as a massive waste for something that won't benefit them.

The implications of this are far-reaching and incredibly polarizing for our state. Not good.

coryrc• 12 years ago

The machine failed once with grit in the bearing before even leaving Hitachi. That it failed again for the same reason should not be surprising. A little steel well casing might break teeth, but it isn't going to fill the bearing with sand.

hga6• 12 years ago

Not according to what I was able to find in a few minutes (http://seattletimes.com/html/localnews/2022992719_berthaseal...):

"Preedy said that when Bertha was being built in Japan, one of the tests performed was to turn on the motors and rotate the cutter head. That’s when testers heard a noise and took Bertha apart. They found that some parts of the machine weren’t moving properly and caused “some metal-on-metal contact and basically damaged the seal assembly for the main bearing,” Preedy said."

This was a manufacturing problem discovered when it was first spun up in a test, as far as I can tell not even involving any digging, just making sure everything functioned correctly (e.g. what NASA didn't do with the Hubble mirror).

devindotcom2• 12 years ago

One of several reasons I voted against this stupid tunnel!

genwin5• 12 years ago

It could hardly have been more obvious that the cut and cover option (trench with a lid "tunnel") was the best choice for the public.

theophrastus3• 12 years ago

Yes indeed! that superior plan was promoted as an alternate by the city folk and was totally squashed at the state level (i watched it happen in committee)

mjt0229• 12 years ago

I was never convinced that the city needed anything more than a surface street. It's a little dicey putting any tunnel there against the waterfront in landfill in an earthquake-prone area. Moreover, it was never clear that the traffic patterns would have been improved by any sort of tunnel option. The whole thing always had the feel of a land grab for real estate developers, too. On top of that, a tunnel was really the worst for Seattle since it wouldn't help anyone get into or out of downtown, just through downtown.

mratzloff• 12 years ago

You and the majority of residents, who were then overruled by the government.

civilian• 12 years ago

This article is 4 years old, written before the tunnel project started, but it clearly lays out the risks. Not only in building the actual tunnel, but also that the city of Seattle (of which I'm a happy resident) is on the hook for any cost overruns. http://www.thestranger.com/seattle/what-could-possibly-go-wr...

Search for the section that starts with "The tunnel-boring machine gets stuck" to read Dominic's assessment of TBM risks.

theophrastus3• 12 years ago

ah gawdbless TheStranger (particularly prior to Dominic's curious departure) but the city is-not/will-not be on the hook for costs associated with the tunnel, overrun or otherwise. It's a state route (as a parallel part of state route 99), it's a state project, it was approved on the state level with only the most superficial approval of the city.

hga6• 12 years ago

Every source I've read about the project says the city is responsible for overruns. The author goes into the exact details of how this is so, even quoting language from the law and how it might be interpreted.

mikeytown2• 12 years ago

Seattle's Tunnel Project is cursed https://www.youtube.com/watch?v=xgIeuSlKQ3w (1:19 sketch comedy)

In Seattle, a Sinking Feeling About a Troubled Tunnel

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