One of my first memories of moving to Portland was being surprised by a drive-in theater. While walking down a street, I came around a corner and saw a fair number of cars all neatly lined up. They were all parked facing a monolith. Light was projected on this giant screen, but I wasn't sure where the soundtrack would come from. It took me a second to realize that the vertical yellow lines were normally used to separate lanes of traffic. This was the Burnside Bridge, it's leaves drawn up like a castle at night.
While rivers tend to be the center of civilizations, most ancient empires and modern cities are founded on them, they can also serve to divide. Many nations and states define their boundaries based on rivers. In ancient times a true river (as opposed to a stream or creek) might as well have been a mountain for all it did to act as a wall. Casual travelers would rather seek a way around than to have to strip down to nothing, hold your clothes above your head and hope you can make it across in such a state. Trades men could never get their goods safely across such a body. And you can forget about an army of men weighed down by weapons, armor, and camp gear getting through.
If you don't happen to carry a boat around with you, the only way to cross is to find a ford, a place where the water is shallow enough to walk across. And these are not always common, you might have to travel days out of your way to find one. When speed is important, a bridge must be created. Any city built on a river will need bridges to maintain commerce and cohesion.
One of Portland's many nick-names is Bridgetown, and it is well deserved. In the metro area there are more than eight miles of major river crossings and untold leagues of minor ones. And Portland's bridges are not just numerous, but famous also.
Going back to Burnside, this bridge is the center of Portland's compass needle. All locations into town describe themselves as being north or south, east or west of this structure. I have crossed this bridge in a car, on a bus, and on foot more times than I could possibly recount. It was designed by Joseph Strauss, whose name graces the mechanism that lifts the bridge leaves, and who later designed the Golden Gate Bridge in San Fransisco.
Nearby is the Morrison Bridge. A near twin to Burnside, this is the most heavily trafficked non-highway bridge, largely because it serves as an on-ramp/off-ramp to a highway. But also partly due to the fact that it replaces two historical bridges, including the first bridge built in the dark reaches of Portland's history. This first bridge was also the largest west of the Mississippi at the time. The current bridge is the largest mechanical device in the state.
Still going upstream we come to the more-than-a-century-old Hawthorn. It is the oldest vertical-lift still in operation, being so old it must be raised four times a day whether river traffic dictates it or not. For many, this is one of the most nerve wracking drives in Portland, with its extremely narrow lanes traveling very close the bridge's truss system and to oncoming vehicles with no dividers.
If the Hawthorn doesn't stress-out driver and passenger alike, then the Marquam usually will. This speedway, which carries the I-5 freeway, has an incredible takeoff ramp for southbound cars. Just after you are sandwiched under the northbound lanes you take a nearly 90 degree turn out over the river and head for a concrete divider. If you are on the wrong side, say you want to head south (left) you will need to be in the right lanes, you will have to play chicken with other cars who have made the opposite mistake.
Heading back to the north is a truly unique bridge, the Steel. Not only does this bridge carry every conceivable means of transport across the river (people, bikes, cars, buses, light rail, street car, freight train), it is a double-decker vertical-lift. Second in age only to Hawthorn. And while a double-decker is not really that unique, the fact that the decks can lift independent of each other is some flexibility that others envy.
A short distance from there is the Broadway. This Bridge makes it's name for being a bit of a fluke. It is a bascule, like Burnside and Morisson, meaning that it opens by lifting leaves. Unlike these other bridges, though, the counter-weights and mechanisms are above traffic in the bridge's superstructure. Not only that, but it is a Rall-type, meaning it rolls open (named for it's inventor, not for this action), not simply rotating.
At the north end of downtown is the Fremont Bridge. Until recently, this was the largest tied arch (a hybrid between a suspension and an arch) bridge in the world. Now it is number two after a new bridge in China. It still has the longest single span (length of bridge unsupported from below) in the state.
Much further north is the St. Johns Bridge, the tallest, most beautiful, and only suspension bridge on the Willamette. The gothic towers are awe inspiring and can only be called "epic".
I will mention briefly the Ross Island Bridge, the unfriendliest in town as it is the most difficult to get on to or off of as it is a tangle of roads on the west bank, and a list of restrictions on the east. It is also extremely narrow and does not share well with pedestrians or bikes. But it will be alleviated soon. For, between it and the Marquam Bridge there will soon be a new one.
The first major bridge to be built in my lifetime, tenatively called Caruthers (for the streets it almost but doesn't quite connect on each side of the river), is on it's way. For multi-use, it will rival the Steel, only lacking freight trains and cars. That's right! No cars! Making it another unique addition to Portland as it will be one of the largest bridges not for, or allowing, cars in the country. It will also be of the stayed-cable type, which is similar to a suspension bridge. Instead of a large cable crossing the length of the bridge with supports tied to it, the supports are tied directly to the towers. This will also be a breathing and singing bridge! It will host a new Max light rail line, the Orange, into South East Portland and Milwaukee, with a stop at OMSI.
Construction on this new bridge starts this summer, so expect to see updates here as things proceed. I'll be keeping a close eye on it. The average build time for bridges throughout Portland's history is two years, but this one is not scheduled to open for four (or, at least the Orange line doesn't start until 2015).
Happy hunting,
Brett
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