Portland is preparing to build its most significant multi-modal downtown bridge in more than 65 years: a new Burnside Bridge.
The city completed Tilikum Crossing in 2015, but that MAX-and-pedestrian bridge is in the South Waterfront district and off-limits to cars, making it a less-traveled, not-truly-downtown bridge. Going back further, there was 1972’s Fremont Bridge, but it’s a freeway span for cars only, like its uglier companion, 1966’s Marquam Bridge. They’re not truly multi-modal, nor are they drawbridges like the other downtown spans, and it’s hard to love a bridge you can’t walk across (the annual single-day Providence Bridge Pedal not withstanding).
Really, we must go back to 1958’s Morrison Bridge as the last time Portland built a downtown bridge for cars, pedestrians and cyclists. And the Burnside Bridge is arguably even more significant, because Burnside Street is at the true center of the city: the only street touching Northwest, Southwest, Southeast and Northeast Portland.
Which is to say nothing of this new Burnside Bridge’s vital seismic resilience, essentially its raison d’être: the ability to withstand potentially the most powerful seismic event in American history — a Cascadia Subduction Zone earthquake, during which all other Portland bridges could collapse. Even in early renderings, the future Burnside Bridge’s anchoring piers seem enormous, almost like concrete buildings unto themselves.
Though construction will not begin in earnest until 2027, Multnomah County has already been shepherding this project for years: I first interviewed representatives about the process in 2019.
But now, if you’ll forgive a bridge pun, the process is ramping up. A final meeting of the project’s Community Design Advisory Group is set for Aug. 15. Once the advisory group makes its recommendation the project team will make its own recommendation to Multnomah County commissioners in early September, and the county board is expected to make its decision by the end of September on what bridge type to build.
BRIDGE DESIGN IN A CITY OF BRIDGES
After initiating the design phase last fall, county officials selected as the new Burnside Bridge’s lead designer Great Britain’s BEAM Architects, designers of prominent U.S. spans including New York’s Mario M. Cuomo Bridge (better known as the Tappan Zee Bridge, and completed in 2018), the Long Beach International Gateway in Southern California (opened in 2020), and the Frederick Douglass Memorial Bridge in Washington, D.C. (completed in 2021).
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I particularly love a bridge in Newcastle, Great Britain (which I visited in 2015) that BEAM partner Keith Brownlie co-designed while at the London firm WilkinsonEyre: the circa-2001 Gateshead Millennium Bridge in Newcastle upon Tyne, an arched pedestrian and cyclist bridge that lifts its entire curved span to make way for passing ships. In a talk at last year’s Structum conference in Lithuania, Brownlie called it the most unique bridge of his career.
In that same talk last year, Brownlie said designing bridges is easy. They’re just two simple components—the deck and the support—and all bridges boil down to just six basic bridge types: beam, arch, suspension, truss, cable-stay, and ribbon. The real challenge, Brownlie added, and the place for both problem-solving and creativity, is more ephemeral: “We design journeys.”
Last week Brownlie was in town to address Multnomah County’s Community Design Advisory Group. It was his latest in a series of Portland visits over the past year meeting with Multnomah County officials and getting to know the bridge site. Among other questions, I asked him: What is the Burnside Bridge journey?
“It’s all about putting yourself into the seats of those bridge users and saying, ‘Where are the high points? What are the objectives? Where can we pause? What happens when you’re stopped and this bridge opens? What’s your experience like?’ That builds up from something simple into quite a complex net of experiences,” Brownlie said. “So that’s where we start.”
The architect has come to love Portland’s collection of spans. “We’re bridge geeks,” Brownlie told me just before that Advisory Group meeting. “The thing that we love doing most is working in cities that promote themselves as cities of bridges. Of course, Portland’s not the only one. You can go to Pittsburgh or even New York. But this is a city of bridges, and there are some incredible ones. The Steel Bridge is incredible. And there’s a legacy that’s carrying on with Tilikum. So there’s an evolution that we’re interested in joining.”
But the Burnside Bridge is particularly significant, Brownlie added, “because it’s the pivot of the city. It’s the spine. It’s what the whole city folds out from. So I couldn’t think of a more important bridge location than that one.”
TWO TYPES, ONE CHALLENGE
Multnomah County has narrowed its selection to two types: a tied arch bridge (like the Fremont) and a cable stay bridge (like Tilikum). The public was invited to weigh in, in a survey that closed to voting at the end of July. Before speaking to the Community Design Advisory Group, Brownlie had not been told which type won, but he was confident of the result, and confessed that public surveys can sometimes create awkwardness when the choice doesn’t align with the bridge designer’s recommendation.
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“The public will judge on appearance and we will judge on 20,000 other criteria,” he said. “So there can be conflicts. The thing I will say tonight is that I could probably have saved Multnomah County some money and told them what the [survey] result would be, because in my experience, people will always enjoy the curvature of an arch, in every case. There is a familiarity with arches that seems to resonate with the public.”
The Burnside Bridge presents a unique challenge. Not only must it possess unprecedented seismic resilience, but it’s essentially two bridges in one, if not three. Obviously it spans the Willamette River. But on the east side it also extends over Interstate 5 and the railroad tracks, and on the west side it spans Tom McCall Waterfront Park. In fact, the additional east-side transit it traverses, not seismic resilience, is why the bridge’s anchoring piers will be so big (well, that and the fact that it’s a bascule-style drawbridge).
The existing Burnside Bridge, essentially a flat deck, manages to span highway, rail and river while still appearing as one composition. The new version will look much different, and for better or worse, less unified as well as less Willamette River-oriented.
In Multnomah County’s online renderings demonstrating how the potential bridge types would look, both the cable stay and tied arch forms extend mainly over the east-side freeway and rail tracks before landing at a point in the bridge deck just a few feet into the water to the east, as if the span over the Willamette were just an extended ramp to a bridge traversing I-5.
“Because of the ground conditions and the seismic issues, you cannot put a column down on the east bank of the river, which means that you’ve got to span the railroad, I-5, and the east side of the Willamette before the first in-water pier,” Brownlie said. “Arches and cable-stays will have very different attitudes towards what happens in that context.”
Like any constraint, the new Burnside’s inherent asymmetry can become an aesthetic asset, depending on how it’s handled. Should the bridge own its asymmetry, or try to minimize it?
PLAYING WITH CONTEXT
On Multnomah County’s website for the bridge project, an operable rendering allowing one to compare the two bridge types offers explanatory text: “CABLE STAY DRAWS EYES EAST,” and “ARCH DRAWS EYES WEST.” But that explanation can be misleading.
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The tied arch type doesn’t extend any further into the water than the cable stay does, so it doesn’t address the natural asymmetry. It’s just that the cable stay version comes with a taller, more vertically oriented tower and thinner ties to the deck, thereby essentially owning the bridge’s inevitable asymmetry by drawing your eye to its vertical structure.
The tied arch’s form is a kind of curving spine that goes the same distance as the cable stay bridge cables, but because it has no tower, its ties are much thicker. What’s more, through its more elongated form, the arch ties more explicitly to the bridge’s huge river-based piers.
In fact, Brownlie called resolving the piers’ bulkiness compared to the rest of the bridge “the number-one issue.” So it’s natural that the more we talked, and the more his ensuing presentation to the Community Design Advisory Group went on, the more disinclined he seemed toward the arch. “I think that cable stayed bridges will deal with that issue better,” he said, “because they’re not so quite so pushy on the river corridor.”
The architect also stressed that the decision should be based on context, now just how one feels about cable stay or arched bridges, or how Portland might build a unique-looking bridge from these common types.
“You start to think not about how you can make it different, but what’s appropriate to the scale of the city,” he said. “There’s a lot of context-driven stuff that doesn’t require innovation, but it does require trying to make something different out of the context.” The bridge’s aesthetic success, Brownlie added, comes from “how it plays with that context.”
In particular, the architect sees the two residential buildings marking the Burnside Bridge’s east end, Yard and 5 MLK—which are taller than any structures on the downtown side of the bridge—as an opportunity. Together, these buildings and a cable-stay bridge tower could create a sense of east-side architectural identity much like the twin spires of the Oregon Convention Center.
“It’s a very interesting site because the Yard building and 5 MLK are kind of monolithic pieces, but in isolation,” Brownlie explains. “A cable stayed tower will punctuate the gap between the two buildings in a very different way.”
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THE WHY BEHIND THE Y
Though only the tied arch and cable stay bridge types are in play, each comes in three sub-types. There are actually six options, not two.
A cable stay bridge could be goalpost style with its tower arms going straight upward, a V tower with tower arms tilting outward, or it could be an inverted Y, almost like two hands clasped in prayer (perhaps appropriate, considering it’s meant to survive an otherwise devastating earthquake). Of the tied-arch options, Multnomah County can choose an unbraced vertical arch with the two arms on each side in parallel, the similar braced vertical arch where the two parallel aches are connected with X-bracing, or a braced basket-handle arch where two slightly inward-tilted arches touch at the top.
“Everyone loves an arch. I love an arch. But are they the right answer to every situation? I would say they’re not,” Brownlie told the Advisory Group. Visually, an arch’s focus is going “end to end,” he explained: in this case across Interstate 5 and the railroad tracks. “Whereas the cable-stay bridge, yes it has cables, but its main visual focus is on the tower. So it’s a visual punctuation.” While the arched bridge form is vertically shorter, it’s also heavier, Brownlie added, “because there’s a great difference between a 10-foot wide steel arch and a six or nine-inch-diameter cable.”
For both the tied arch and cable stay trios, he offered the Advisory Group a gold, silver and bronze option, but then went on to suggest eliminating in each case one of the three. “I think the unbraced arches and the basket-handle arches are equally good but equally challenged,” he began. “I think the braced arch doesn’t get a place on the podium at all.”
Moving to the cable stay trio, Brownlie singled out the inverted Y as the potentially most unique, in part because its tower at the top would be one form. “Most cable stayed bridges are like the Tilikum: two sets of towers,” he explained. But with the inverted Y, “we don’t have that. So there’s immediately a rise in the distinctiveness of a cable-stayed bridge.” Brownlie was quickest to dismiss the goal-post cable stay bridge, because “it’s not novel even in Portland.” He even suggested the choice would be boring: “I think it offers less than the site deserves.”
He awarded a gold option to the inverted Y, and silver to the V tower, but added that the latter “is not an urban form per se. I think it’s doing something against the grain of the buildings that I find slightly uncomfortable. I think it’s perhaps a bit self-confident. From an architectural point of view, the inverted Y tower is a clear favorite. It’s a country mile better than the response of all of the other types. I think it’s an urban solution, I think it’s quite sophisticated, and I think it’s quite modern. And it has the best ride-through experience. I think it’s pretty unique in the Pacific Northwest. I mean, it’s pretty unique anywhere.”
On Multnomah County’s website, Brownlie’s preference for the inverted Y comes through most powerfully in images showing the experience of being on the bridge. Driving east or west, the inverted Y is framed by the Yard and 5MLK buildings, while nearly all of the other bridge types (except for maybe the braced basket-handle arch) compete with them. And from a pedestrian standpoint, the inverted Y offers the most unobstructed view ahead.
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SURVEY SAYS
Following Brownlie’s presentation to the Community Design Advisory Group, public survey results were revealed by Multnomah County Transportation Public Information Officer Sarah Hurwitz. After more than 19,000 responses, the public chose a tied-arch bridge type over cable-stay, just as Brownlie predicted. But it was a relatively close vote, Hurwitz noted: 55 percent to 45, and it came with an asterisk. Among specific sub-types, the cable-stay V tower got the most overall public votes, with the tied arch braced basket-handle second.
Brownlie’s preferred inverted-Y tower came in fourth in public voting. He warned that renderings can be misleading.
“My gut, or my experience, tells me … that the V tower won’t be as successful as the images tell you that it is. I was quite surprised,” he said of the renderings. “I can see why there was a preference [for the V tower], because I think … I won’t say I think we’ve over-served the V tower but I think we’ve under-served the inverted Y. It’s very difficult if you’re looking at these things and you say, ‘I like that one and I don’t like that one,’ because the images tell you what you like. I think despite that, my preference comes despite what the images tell you. And I think there’s a great deal of that happening with people who are speaking with their eyes.”
While the tied-arch type won the overall vote, Advisory Group members seemed to prefer cable-stay. “The tied-arch option doesn’t really address the river at all. I think it fails for that reason,” said Paddy Tillett, a retired former ZGF Architects urban planner and transit designer. “It’s a fundamental thing. It’s got to be something that really addresses the river. And the tied-arch doesn’t. It simply doesn’t.”
Tillett’s point relates to what Brownlie said about designing an experience. Driving across a new Burnside Bridge, a tied arch would actually obstruct the view out to the river, acting like a fence with its thicker ties. The cable-stay would allow drivers, pedestrians and cyclists to see more of the view, thanks to its combination of taller tower and much thinner cables.
The V tower and the inverted Y tower would be the most expensive options, but the Advisory Group was cautioned not to focus on costs at this point, because they are so approximate. Another Advisory Group member, Bob Hastings, who for over 20 years oversaw architecture and urban design for TriMet, drove home this point even further.
“What I want to put into our thought process is investment,” he said. Looking at the 100 to 125 years of a bridge’s life, an extra $30 million spent today would be “an incremental bump over the lifespan of the project. This is not meant to be an excuse, but we’re looking forward and we also look back. There were forward-thinking folks 100 years ago who recognized they were going to be paying for something far beyond what the cost was, because they recognized they were making an investment. And this project is an investment.”
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At the end of the night, the Advisory Group voted to eliminate from consideration two of the six sub-types: the cable-stay goal post and the tied-arch type: the braced vertical arch. A week later, on August 8, they eliminated an additional option: the unbraced vertical arch. That leaves three options: the inverted Y cable-stay, the V tower cable-stay, and the basked-weave ach. The Advisory Group will return for additional deliberations once more, during which time a definitive recommendation is expected to made. The Multnomah County Board of Commissioners will make the final choice.
As things stand, Brownlie’s first choice, the inverted Y cable-stay bridge, is the underdog but, considering, not out of the running. And even though the public prefers a tied arch, if the combined preference of architect and Advisory Group carries weight, Brownlie might yet get his cable-stay bridge.
