Saturday, September 27, 2014

Vancouver Ave. Bridge

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The next Columbia Slough bridge on our little tour is the one that carries N. Vancouver Ave. over the slough. The current bridge only dates to 2011, but it's the third bridge at this location, with history going back nearly a century.

As planning for the Interstate Bridge heated up in the early 1910s, local boosters argued over which street would be Portland's main approach to the bridge. The thinking was that winning this prize would lead to a bonanza of traffic and shoppers and general Progress. The two leading candidates were Vancouver Avenue, and Union Avenue (now MLK) a bit further east. The Union Avenue boosters won out, and the street got a bridge over the Columbia Slough in the style of the main Interstate Bridge. Vancouver Ave. had some sort of temporary connection to the bridge construction site, which was supposed to be demolished after the bridge opened, but the city threw a bone to local business interests and let them keep it for another two years on a trial basis. Which encouraged Vancouver Ave. boosters to lobby for a permanent slough bridge.

I'm not sure what happened to that original temporary span, but as far as I can tell there wasn't a bridge here by the mid-1920s. In 1927 there was a proposal to reuse a discarded old span from the Broadway Bridge here, similar to what happened with old Burnside Bridge parts being reused at the Sellwood, Lusted Rd., and Bull Run River bridges. Unfortunately Portland's city engineer concluded the old span was much too heavy for the site, and it would be cheaper to build an entirely new bridge than to build all the heavy supports needed for the Broadway span.

By 1929, local boosters were once again lobbying for a Vancouver Ave. extension, slough bridge, & connection with Union Ave. This time the idea got traction, although the powers that be decided to do it on the cheap; in August 1931, it was decided the new bridge would be a wooden structure, with only the parts the general motoring public would see done in concrete. A historical assessment done for the city in 2009 explains that this is actually a Conde McCullough design, believe it or not. As the state bridge engineer, he was responsible for mundane bridges as well as crown jewels along the coast, and this type of bridge was designed to be an affordable small bridge, with better aesthetics than a plain old all-wood bridge.

In June 1932, the county applied for Corps of Engineers permission to build the bridge. Permitting dragged out for a while, as the slough was then used by fishing boats and a bit of shipping traffic, as hard as that is to imagine today. Objections were eventually sorted out, and a May 1935 construction photo shows the bridge 50% complete. I didn't run across a story about the actual completion of the bridge. You'd think Vancouver Avenue would have hosted a big ribbon-cutting party, after all the lobbying that went into getting it built.

In May and June 1948, floodwaters from the Columbia and Willamette inundated the Vanport area and other large tracts of the city. To try to control the flooding, engineers built an emergency dam around the Vancouver Ave. bridge. It seems that a log raft somewhere upriver had broken during the flooding and a large number of logs had jammed up against the bridge anyway, so they decided to just dump rocks and gravel on top of the log debris until they'd blocked off the slough. Construction photos look messy and chaotic but apparently the dam did actually work as designed, preventing more flooding across North Portland.

In 2008, the wooden bridge supports were damaged by a brush fire that began in a transient camp under the bridge. It closed to vehicle traffic after the fire and was deemed unrepairable, but it remained open for bikes while the city figured out what to do next, and Vancouver Ave. boosters once again had to lobby for a new bridge. The old bridge was fully closed for demolition in April 2010, and its award-winning (and less flammable) replacement finally opened in May 2011. The new bridge features wide bike lanes and a variety of artistic touches, I suppose on the theory that whenever you replace a McCullough bridge, even a minor one, you have to make it a little fancier than you otherwise would. Maybe if you don't he appears as an angry ghost and makes fun of your third rate engineering skills or something. I haven't seen any reliable reports of that actually happening, but (I suppose) why risk it if you don't have to?

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