Here’s an argument that keeps coming up: The light-rail tunnels that Sound Transit is digging under Capitol Hill are, basically, the same as the proposed deep-bore tunnel downtown—but you don’t see tunnel critics complaining about the light rail.
Sorry, no, they’re not the same. Even if you lerv the deep-bore tunnel, they’re different animals. Different engineering, different financing, different function.
“They are two very different projects,” says Sound Transit spokesman Bruce Gray. “We are using similar technology, but the scale is very different between the two.”
The twin bore tunnels under Capitol Hill (like the tunnels under Beacon Hill) are much smaller. At only 21 feet in diameter, they have an area of 346 square feet. The proposed deep-bore tunnel, according to the presumptive bid, would nearly three times the diameter. At 58 feet wide, that’s 2,642 square feet in area—or a 7.6 times larger hole. The downtown tunnel is the widest deep-bore tunnel ever attempted.
More after the jump.
That’s not to say smaller tunnels don’t encounter problems. Some don’t. Other do: Two of the machines digging the Brightwater sewage treatment tunnels in north King County (about 15 to 20 feet wide) got stuck in silty soil, driving up costs beyond their bid price; the Beacon Hill tunnels for light rail also ran over budget.
But if the deep-bore tunnel has these problems—and the odds are stacked that it will hit a snag—the ramifications are likely to be bigger, harder to solve, and more expensive.
Light rail is also financed differently. It’s funded by a sales tax, and Gray notes that Sound Transit has the authority to extend the tax to pay for the project. Or, alternatively, the scope of the project can be reduced. In fact, due to a drop in sales tax revenues, Sound Transit has already cut back its plan. But light rail to the suburbs is a more scalable project because more of the components are expendable (remove a stop, delay an extension, build a less expensive station) without fundamentally compromising the project.
In contrast, the $4.2 billion deep-bore tunnel has a state financing cap on the project. And it’s far less scalable because most components are vital to traffic management in the city’s core. Left incomplete, if the money runs out, the tunnel project would leave unconnected streets downtown, unfinished portals, a dangerously unstable viaduct left standing, or even a tunnel that doesn’t connect from end to end. Given that $300 million from the Port of Seattle isn’t shored up, $400 million from tolling is considered unworkable (even thought it’s needed to complete the project), and the contingency fund is more than half gone before the project has begun, the financing for this project is, at best, tenuous. At worst, it means there may not be enough dough to complete the basics.
And last: Seattle is long overdue for a rail system. There’s no other way to build a station on Capitol Hill hill without digging a tunnel. Downtown, where we need to replace the capacity for six lanes from the Alaskan Way Viaduct, we have other options.
People argue about that? Really? Oof.
Not to mention you’re talking about drilling through a hill, not digging below sea-level.
(also, you’re missing an M behind $300)
The reason I bring it up is because the engineering argument against the tunnel is a terrible one. That doesn’t mean there aren’t plenty of other good ones, but all this scare-mongering about THE BIGGEST TUNNEL EVER DUG!!! are just inaccurate and misleading. Yes, it’s a wide tunnel, but also a short one, by the standards of these things. And the only reason it’s the “widest ever” is an accident of timing. There’s been a new “widest ever” every year or two since forever, and there will be a new “wider than Seattle” tunnel within a year or two of ours — if they build it. It’s a terrible argument.
I agree that rail is a wiser choice and the tunnel is a terrible return on the dollar and a bad idea, but not for this reason.
good point on the distinction. but definitely worth remembering that even the smallest tunnel projects can run into unforseen obstacles: http://www.centraldistrictnews.com/2010/…
Wait – by “people keep arguing” do we mean simply “Fnarf keeps pointing out and la la la la I can’t hear you”?
@5) I wasn’t thinking about Fnarf. I don’t recall him making a comparison to the light-rail tunnels.
If they can dig the BART tunnel, they can dig the SR99 tunnel.
@2 is correct.
@3 is still a clueless n00b who would die in the first earthquake in a smoke-filled Deeply Boring Tunnel when we get hit by a factor 9 earthquake during a big freeze and the Seven Gates of Hades seal shut, never to open again, his body entombed deep beneath the earth, his charred corpse endlessly to wander the tunnel in search of his soul, which he sold to his foreign masters who employ LESS local labor to build a MORE EXPENSIVE tunnel than the other options.
Taxpayers for the loss. Cause we can’t afford to build both the 520 replacement bridge AND the Billionaires Tunnel and that’s something nobody is willing to admit to you guys, cause you can’t do math and still believe Republicants who tell you that you can have your tax cuts AND reduce the deficit.
Exactly, every one knows the dbt is the same as Ballard Bridge!
Sorry to confuse. Thought you might’ve been referring to Fnarf. I saw your exchange with him on it in this morning’s light rail station thread, and seem to remember several vivid occasions he’d already tried to get through with that point.
Still, on the whole I suppose commenters read these threads more closely than Slog posters ever will, so n’enculons pas des mouches…
@WiS
go suck a hot dog.
I have to agree with Fnarf. The argument that this is uncharted technology is overblown. The boring machines will operate in exactly the same way that ST’s did. The tunnel is also not in bad soils or below sea level–it turns and goes under downtown Seattle in relatively good soils.
There are risks in any construction. Deep bore technology is rapidly improving and the main risk is a breakdown of the machine and the need to pull it out and restart it again. The design-build contract means that the contractor is accepting more risk than a simple construction contract.
I don’t recall tolling being ruled unworkable or the Port’s contribution to be seriously in doubt. Dominic is guilty of the same type of misleading arguments he posts about here. Plenty of disinformation on all sides.
We must stop the Deeply Boring Zillionaires Tunnel before we are Run Over by Costs! We must Option the Surface! We must re-Via the Ducks! Republicans!!!
@12 — I think the main risk is finding a void space or creating a sinkhole under the foundation of a historic building or two. Sound Transit can use the sales tax to buy some houses on Beacon Hill. I doubt the DOT can buy and repair the Federal Building, for example.
if you don;t want to compare those two types of tunnels, then also stop referring to the vote against a cut and cover tunnel as a rejection by the voters of any tunnel.
This scalability bugaboo needs to be lanced in the bum and deflated like the paper tiger that it is. This tunnel is scalable because it has a spending cap! If there were a means to get more money, that would, by definition, preclude scaling it down. Think, kids.
When the money runs out, there’s your scaled to fit tunnel. I’m a glass half full kind of guy and for my money, 80% of a tunnel is better than no tunnel at all. In fact if they only dig 50% of the way, well shucks, that’s half a tunnel people! You can sit there and have a pity party about the other half not being there but if you go through life focused on the negative you’re going to wake up one day and realize that an awful lot of good things have passed you by.
Some day, we will be looking at our new tunnel, or most of our new tunnel, and will be grateful we went for it and got as much of a tunnel as we could afford rather than no tunnel at all.
There are lots of super-distracting typos in this. But it’s a good point.
@16: That is easily one of the dumbest things I’ve ever read, and I’m going to pretend that you’re doing it on purpose.
I like the implications of “boring machine.”
Look, it all comes down to the money and the risk factors.
We have not enough of the former and way too much of the latter.
@ 12) This is false:
As for this…
The state says the traffic diversion caused by tolling are unworkable, but also says paying for the project without $400 million from tolling is unworkable. Go figure. The Port of Seattle has approved a nonbinding resolution to help with the tunnel, but it has not identified where its money is coming from (property taxes are down, revenue is down), nor is it under any legal obligation to fund the tunnel.
@ me) “traffic diversion… is unworkable…” Time for some tequila and a nap.
Wow, you forgot about the part of the light rail tunnel where they have to dig DEEP under the mountlake cut to connect Capitol Hill to Husky Stadium (and then onto 45th Street eventually). Tests showed that the soil was too soft, it forced engineers to dig even deeper, far below sea level.
Oh, you wanna see a complaint?
Let’s start with the cost per mile of LINK being $167 million.
5 miles of LINK = total budget shortfall this year.
Chew on that.
@21, see, THAT’S a good argument. The traffic diversion without tolling is only fair, but unaffordable; the traffic diversion WITH tolling is terrible. You’re paying for a luxury replacement of about a third of the viaduct. I think this is called “making everyone unhappy”.
Not to mention the light rail tunnel will immediately carry 76,000 riders per day when University Link is opened, up to 136,000 riders per day when North Link is completed. And it’s in a location (a giant hill) where a tunnel is actually needed.
Compare that to the much more expensive Viaduct tunnel on flat ground that will only carry 45,000 riders per day, and only cars. Oh, and driving your expensive car with expensive insurance and burning expensive gas will cost you a toll twice as expensive as having a light rail train pick you up and zoom you across the city.
Is it too late to convert the viaduct tunnel to light rail?
All this blather against a tunnel reminds me of the utter and complete teabagging-before-teabagging-was-teabagging hysteria of the good folks in Gig Harbor bitching and moaning about how awful it was for them to have to pay for a second span of the Tacoma Narrows Bridge. Then they got their second span, and it seems like they’re all pretty damn happy.
Anyone want to go back to the days when I-90 wasn’t finished? It went through Mercer Island and Seattle on surface streets. There were reversible lanes where many, many morons and their victims died because they couldn’t tell the difference between an arrow (“Go!”) and an X (“Don’t Go!”). Well, that’s your so-called “Surface Option.” It was only after we laid a whole bunch of concrete that it even became feasible for light rail to cross Lake Washington.
I’m a big supporter of transit. We’ve spent (and continue to spend) an ungodly amount of money on light rail, commuter rail and buses. But the fact remains that we are still dependent on automobiles, trucks and buses, and two limited access freeway lanes in a tunnel underneath the Convention Center in this narrow isthmus of ours are not sufficient to serve all of the north-south traffic between Canada and Mexico.
Now we’re getting somewhere, Dom. You’re actually reporting facts that we can all discuss, even those of us who don’t think building a tunnel to reclaim the waterfront is the worst idea in the history of mankind.
I’ll grant your point – this tunnel is trickier than the light rail tunnels. Shit, it may go over budget. But here’s the thing. If, hypothetically, the exact same tunnel were being built for light rail, you’d all be 110% in favor of it, to hell with overruns and risk. Because its for cars, however, you are making the same lame tea-bagger arguments as those who tried to stop light rail, the monorail, and every large engineering project for that matter. If we always listened to the cautious and fearful among us, we’d never build anything worthwhile.
Sorry, but for this and reasons pointed out by Fnarf, the engineering/cost argument isn’t especially compelling for those of us not already compelled.
As for the Ballard bridge comparison, does that bridge turn the downtown waterfront into a park? No? Then it’s apples to oranges.
another dumb commenter vs. commenter battle, missing the point completely. zzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
Dig the damn tunnel, already.
@ 30: “If, hypothetically, the exact same tunnel were being built for light rail, you’d all be 110% in favor of it, to hell with overruns and risk.”
Rephrased:
“If, hypothetically, we were having an entirely different argument, you’d come to an entirely different conclusion.”
Well, duh.