A first look at the Tilikum Crossing

Tilikum Crossing (photo by Brian Libby)

BY BRIAN LIBBY

It is still 15 months away from opening, but Portland's new bridge, the Tilikum Crossing, is now close enough to completion that its primary forms have been finished. That was clear at last week's connection ceremony, in which local dignitaries and press walked from both sides of the bridge to meet in the middle. And with the 1,720-foot span's signature towers, deck and cables in place, we can start to consider its place on the skyline and on the river.

My first impression of Tilikum Crossing, a cable-stay bridge designed by Bay Area firm MacDonald Architects (in partnership with engineering firm HNTB and others ), is a good one. Whether it's the shape of the towers or how the bridge span itself juts out in the middle, there is a unifying language of angles here that gives the bridge up close a sense of movement. The striking white cables coming down to its surface from two towers mimic the angle of Mt. Hood, and the entire bridge possesses a compelling kinetic energy. 

As one walks or bikes onto the bridge, as a group of us did for the connection ceremony last week, Tilikum Crossing's sense of proportion and balance becomes apparent. The span itself, thin and elegant, has a gentle slope that goes high enough to provide clearance for boats and ships, but maintains no more than about a four to five-percent grade. Standing in the middle, the bridge's pedestrian and bike path juts out -- a belvedere, it's called -- in a way that prompts one to focus on views of the river, treeline and skyline. Jutting out like that also reduces wind by diverting its flow.

Tilikum Crossing (photos by Brian Libby)

It's not a stretch to predict that Tilikum Crossing could become a primary visual symbol for Portland. As a friend told me recently, one could easily imagine some future Portland logo in which Mt. Hood is bookended by the bridge's two towers, with its cables parallel to the slopes of the mountain. And after more than 40 years, it's exciting to see our so-called Bridge City add another span to its connection.

Furthermore, I think the Tilikum Crossing designers got the contextual proportions right. MacDonald and the rest of the design and engineering team (including HNTB) labored to get the size of the towers down, even employing a unique type of cable-stay bridge to do so. In most cable-stay bridges, the cables are connected from the deck to the tower columns at the center and are independent of each other as they go down to the other side of the deck. Tilikum Crossing is a saddle type in which the cable goes from the deck, up through the tower and down to the other side. That allowed for a shorter, narrower tower.

All that said, the one complicating factor with regard to evaluating Tilikum Crossing could arguably be the proposed bridge by another designer earlier-on in the process. Boston-based designer Miguel Rosales and his firm, Rosales + Partners, were hired as a design consultant in the late 2000s and in 2009 proposed a one-of-a-kind hybrid bridge that combined the cable-stay and suspension bridge types. "I’m excited about this,” bridge advisory committee member Guenevere Millius, who now chairs the city's Design Commission, told Portland Monthly when the hybrid design was introduced.  “[Rosales is] finding a great solution given the constraints.”

Hybrid bridge proposal (image courtesy Rosales + Partners)

Some bridge designers, including MacDonald, who eventually got the job over Rosales, argued that a suspension bridge wasn't right for this span, that true suspension bridges such as the Golden Gate or the local Saint Johns Bridge are intended for longer spans. Yet the Rosales hybrid bridge design found strong favor with the local design community. The Rosales design probably would have cost more, but it also was an exceptionally elegant-looking bridge, at least in renderings. Yet Tri-Met instead decided to go with a more conventional cable-stay bridge and hired MacDonald over Rosales to make it happen.

"We're not taking advantage of an opportunity to do something great," Lloyd Lindley, a former Design Commission chair, told The Oregonian after the selection. "We're doing something that's an oatmeal, plain-Jane solution: We know it works and it fits our budget."

But make no mistake: both Donald MacDonald and Miguel Rosales rank among the nation's most prominent and acclaimed bridge designers. MacDonald's portfolio includes iconic projects like the east and west spans of the Bay Bridge, for example. MacDonald is a major talent with an impressive track record.

Was the Rosales hybrid prettier than MacDonald's cable-stay bridge? It's hard to say for sure. It's a comparison between a rendering and a finished bridge. That means MacDonald's design had to be subject to cost-cutting measures as well as changes from a wide spectrum of stakeholders. Rosales's rendering was never subject to that kind of scrutiny.

I found the bridge in Rosales's rendering to be a little more clean-lined and slender than the MacDonald bridge I walked across last week. But I also found the real-life Tilikum Crossing to be a better-looking bridge than I felt like I saw in the renderings. And MacDonald's design, with its angularity, arguably has more energy than the Rosales design. I like its zigzagging geometry. Would I trade it for the hybrid? Maybe, but it also may be a bit of a false choice. While cable-stay bridges are ubiquitous in America and no one has ever built a hybrid cable-stay/suspension bridge, that's not something likely to resonate strongly with the general public. (Although Rosales's nod to the St. Johns might have.) There was never an obligation for Portland and Tri-Met to choose a one-of-a-kind bridge type, and uniqueness of type is not necessarily the most important yardstick.

And besides, it's really about what kind of finished Tilikum Crossing we are getting, not how it compares to past iterations. Luckily, there's a lot to like here, and this bridge seems likely to find great favor and popularity as the years go by. I'm looking forward to taking another walk across its span.

 

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Comments

[Charles]

Thanks Brian
I liked your perspectives on the bridge being built and also acknowledging the alternative plan and questions around what may have been missed. Your photos captured an attractive bridge, even in contrast to the lowest common denominator Columbia Crossing bridge design.
I also appreciated your previous post on the Portland Design Commission and especially how we bring more of their engagement into the neighbourhoods. Having been involved in the Division Vision process for ten years it is challenging to encourage good design and developments without more rigour encouraging the good over the most profitable to the developers. We are struggling with the fallout from this, amongst some of the good projects we also have some of the very mediocre developments that have been created on Division.
And this leads me to my third observation and that is the fall off in people commenting on your posts? I still find you the go to spot for tracking what is going on with the architecture and built environment scene in Portland. I live in London now and miss the sort of perspective you bring over here. But it does make me wonder why the fall off. Are design people less interested in the topics you are discussing? Are people just too 'busy'? Have you a sense of what has changed? It was not all that long ago that posts of yours would have ten or more comments. I don't see much of that now. Maybe this is part of the fallout after 2008 market dip?
Regardless, I wanted you to know how much I appreciate your work and I think I also wanted to see if others who read you have feedback or thoughts as to why the feedback and comment debates that used to go on here have ebbed?
Thanks again, Charles

[Brian Libby]

Thanks for your comments, Charles. Glad to hear you liked the posts and that they share a lot of parallels with your experience. To answer your question about comments, things changed significantly a year or two ago when I changed the rules to require everyone to sign in with a service like Facebook or Twitter. I was tired of there being anonymous comments that frequently were personally insulting or generally snarky. To be honest, I think I may have made a mistake in initiating this change, and I have considered switching back. It's nice not getting frustrated by brash anonymous comments, but I do miss the sense of conversation.

[Brian Libby]

Charles and everyone, I have actually just turned off the comment-registration function, so as of right now people are once again free to leave anonymous comments. Hopefully I can bring some people back into the commenting fold.

[Jeff Belluschi]

Thank you for the reversal Brian. It is a welcome change. I just hope readers respect your great writing and are respectful of journalistic integrity and the ethical component of thoughtful commentary. This is a community for the better good.

[Justin]

I think part of the problem was that the service didn't work very well. I tried commenting a couple of times with my twitter account, and it would never work. So, I kind of just gave up. Anyway, love the pictures.

[Charles]

Sounds good Brian. And I'll do my bit in comments I may add to support this to be an engaging community where I can treat views different from my own respectfully.