More thoughts and info on the Willamette bridge process

Understanding the process for the Willamette River bridge has been difficult.

In the last few days since TriMet announced its selection of Donald MacDonald as the bridge's designer (his cable-stay Ravenel Bridge in South Carolina is pictured above), it has seemed that Miguel Rosales's popular "Hybrid" concept was being unfairly and unfortunately discarded. That may still hold to be true, but it's not necessarily a done deal yet.

As it happens, bridges are a little different from buildings in terms of how they separate the selection of a bridge type and then the architect/designer who designs them. So if Donald MacDonald were to design a bridge based on Rosales's hybrid concept, it wouldn't necessarily be abnormal for this sort of structure.

In the industry, I'm told, designers who are charged with creating a bridge's concept aren’t necessarily always the ones who design them. In fact, this happens somewhat frequently. Having Miguel Rosales design the hybrid would still be best, but MacDonald's firm is certainly capable of making it happen and creating a quality bridge.

The Willamette River Bridge Advisory Committee will be holding a meeting this Thursday, May 28, and this is actually the first time the committee has met since February. The committee, headed by former mayor Vera Katz, previously recommended a cable-stay bridge, but that was only when the choice was between a cable-stay and the wave-form design.

Rosales's hybrid was a late addition to the process, so much so that it doesn't seem completely clear if TriMet has given it strong consideration. Insiders at the agency seem to have wanted a more traditional cable-stay bridge all along, and now they have an official recommendation for that type from the WRBAC signed by Katz. When the WRBAC meets on Thursday, I'm not sure if it will be considered.

Meanwhile, here is a statement from TriMet:

As we did in the first phase when we were evaluating various bridge types, TriMet utilized management best practices and relied upon the National Constructors Group (NCG) for an independent cost estimate to build the wave frame and cable-stayed bridge type. NCG is an industry leader and a firm of retired bridge engineers and contractors who have been hired by government agencies throughout the U.S. to do independent analysis on the cost to build major infrastructure, including bridges.

When we began detailed estimates back in December on the wave frame and the cable-stayed, they provided the cost estimate for how much it would cost from a contractor's perspective. Based on NCG's estimates, WRBAC selected the cable-stayed design type because the wave frame was more expensive and with a lot of unknowns and risks associated with it. NCG is an objective third party that has no investment in the design.

The process starts with the engineering team developing a computer model of the bridge and then applying load scenarios (how it will be used) to the model to determine how big structural members need to be. After the structural member sizes are known, the engineering team develops a list of quantities for each material such as concrete, cables, etc. This information is then given to the NCG who uses it to develop a full workup of labor, equipment, material costs and production rates to generate an independent cost estimate. 

NCG did not ask the architect for cost estimates as they have experience providing full cost estimates from the ground up for both cable stayed and suspension bridges since they have built these bridge types around the US. This methodology provides a more accurate estimate compared to engineers and architects who typically develop estimates by square footage.

Admittedly, I was wrong about some of this. There's a learning curve when it comes to understanding bridge selection process versus buildings.

In my previous post, I wrote, "If Rosales is correct that Trimet never contacted his team, that to me means that Trimet has misled the citizens of Portland by pretending to conduct a reasonable and open minded, public-influenced process that really never was." Not to split hairs, but I was never accusing TriMet - just raising a concern. It now seems there was no deliberate misleading, which I'm glad to see. And I apologize to TriMet if this seemed like an attack.

That said, it still would have been much better for Rosales to be selected, and choosing MacDonald as designer may be a precursor for TriMet choosing the standard cable-stay design. If so, that would bring us to the same terribly, wrong decision on TriMet's part - just done through a proper process.

Both MacDonald and Rosales have experience with significant bridge designs, but from what I've seen of the MacDonald resume, there is only one completely new bridge, the previously mentioned Arthur Ravenel Bridge in South Carolina. It's a handsome enough cable-stay bridge with a triangular pattern, although similar to other cable-stay bridge patterns you'd find being built recently in China, Jordan, New York, Egypt and Dubai, and similar to what would be built in Portland. I and others worry, however, that this more common off-the-shelf type wound't  relate in any way to the city's other bridges, and it would likely be taller and fatter than the hybrid.

Look, I'm sure TriMet is trying to do the right thing, and these are people who live here too. But the agency still may be too willfully cheapskate and overly conservative in picking a design that Portland will live with for a century or more, and right in the center of the city.

In the weeks ahead, there may be a case made that the hybrid is more expensive. And to an extent, that may be true. But Portland needs the best designed bridge possible.

Comments

[pylon]

While I respect Rosales' unique attempt to come up with a design that relates to the other local bridges, sometimes a clean break indicates fresh thinking and a move away from a provincial mind-set, or "design-set" in this instance. I'm not saying completely ignore the other bridges, just not be hampered by them.

In addition to the "look" of the bridge, I hope the WRBAC team takes the users' experience into account as well. Ask anyone who has worked in the Portland Building what happens when the human element is left out of the design equation.

[Thor]

WTF? This is such a broken complex sentence... I have no idea what the author wants to say....
"In the last few days as TriMet's decision to select Donald MacDonald as the bridge's designer, it has seemed that the bridge an overwhelming majority in the design community and public at large wanted, Miguel Rosales's "Hybrid" concept, was being discarded. That probably will still hold to be true, but it's not necessarily a done deal yet."

Doesn't anyone ever read their posts aloud before posting? Guess not.

[Brian Libby]

Thor,

Thank you for the correction, but I'll pass on the attitude. You're right: I was in error typing that sentence. But I'd hope intelligent readers like yourself would see the wood for the trees.

Incidentally, I loved your work in Marvel Comics.

[Brian2]

Both cable-stay and hybrid bridges can be beautiful if well designed. The fact is, no bridge has been designed yet and all we have are bridge types. Let's let the process work and reserve final judgement until we have working designs and accurate cost estimates to choose from (yes, cost is a critical consideration albeit one of many considerations). I, for one, am looking forward to a fresh perspective from McDonald.

[Brian Libby]

Fair enough, Brian2. I hope you're right!

[low cost homeowner insurance]

I love the bridge design but in this day and age want my elected leaders to make decisions that also factor in costs and economics. Finding politicians that are conservative with taxpayers' money is a hard thing these days.

[JR]

It seems like the Rosales design is artificially "wavy".. Why not just move forward with a traditional cable-stay that does the job just as well and at less cost? What is aesthetics? Does form follow function or vice versa?

[pylon]

It's too bad that we can't have the bridge alignment lined up such that Mt. Hood would be directly in the "sights" that the V-shape provides. It would be a nice straight-ahead view for those heading east, and add some site specificity.

[Steve]

What sort of “public-influenced process” has there been? Is there a web site or article that describes this public process, because I missed it?

I have been involved with the Sellwood Bridge Project, which has been an engaging and enjoyable public-influenced process. If you want to check-up on the process, it is clearly explained here:
www.sellwoodbridge.org

[Steve]

In Randy Gragg’s (12/08) interview with Miguel Rosales, Rosales seems to anticipate being involved through the entire process.
“I am supposed to stay through the process. I will do some guidelines for what they can change or not. But I don’t know if I will prevail. There is enormous pressure to cut costs. Unless the city is very involved, I don’t know what the oversight is in your city. Unless someone really understands the technical side, they can’t really help.”

[Nate G.]

It seems to me that in the midst of all the sturm und drang over whether Tri-Met did or did not do Rosales wrong, we're missing the real story completely.

I would suggest the real story is this:

Somehow, at some point over the past couple months, with no fanfare that I'm aware of, what had once been an extremely ugly, off-the-shelf, inappropriate-to-its-context generic cable stay bridge transformed itself into a rather lovely, unique (as far as I know) V-towered variation on the cable stay that looks, at least in the one rendering released, as good or better than Rosales' hybrid design in the real-life context of the Caruthers Crossing.

So the story I would love to see someone, anyone report on is this: What happened here? Where did this V-towered bridge (for lack of a better term; what is this thing actually called?) come from? Is the old ugly cable stay really now off the table completely? Are our only two options now the nice new V-towered variation on a cable stay and Rosales' equally nice suspension/cable stay hybrid? Is the situation now then a win-win, whichever choice is made? Are there other renderings of this new cable stay floating around anywhere? Does it only look good from the one angle they've released, or is it as nice from all angles as that one rendering suggests?

[Brian Libby]

That's a great point, Nate. I've thrown around the "cookie cutter" term, but it's true that the V-towered bridge is an improvement on the other cable-stay. However, the V tower is very common throughout the world, and I think the Rosales Hybrid is still nicer. But you are indeed correct that this is no longer just about cable stay and hybrid, but three options.

[Earl]

I too would like to know how this new approach was selected, but I know it would be easier to garner support for the proposal if the public had been more engaged in weighing the pros and cons of the competing proposals.