12th Avenue Viaduct

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Today's installment in the ongoing bridge thing takes us to another unlikely spot, the 12th Avenue viaduct over Sullivan's Gulch and Interstate 84, just south of Lloyd Center. I am not, generally speaking, interested in freeway overpasses as part of this project, but this is a somewhat interesting exception. The key thing here is that this bridge, and the ones further east for MLK and Grand Avenues, are much older than I-84, and were built when Sullivan's Gulch was just a ravine with a railroad running through it.

Even that, by itself, probably wouldn't be enough to merit a blog post, but it turns out this humble overpass is a minor design by the famed Waddell & Harrington engineering firm. They're better known for designing the Hawthorne Bridge, the Steel Bridge, and the Interstate Bridge here in Portland, the Sandy River Bridge in Troutdale, the Union Street Bridge in Salem, and (according to Bridgehunter.com) the OR-99 bridge on the Columbia Slough, and a railroad bridge over the Willamette south of Harrisburg. So this is a very obscure cousin of all those well-known local bridges, and many others across the country. It's not particularly photogenic, but the bridge railing does look a lot like the one on the Hawthorne, so there's at least a little family resemblance. And more importantly, it's very, very obscure. Gentle Reader(s) (yes, both of you) out there probably realize how much I gravitate to obscure stuff.

I was reminded of this structure recently when working on a post about the Baltimore & Ohio Railroad Bridge #463 in Cleveland, oddly enough. I came across a blurb by J.A.L. Waddell about his dislike of the "jackknife bascule" design used by said bridge. I started reading his Wikipedia bio (which insists his firm also designed Cleveland's Detroit-Superior Bridge, which I'm not sure is true), and then wandered off on a tangent to see what else around Portland Waddell's firm might be responsible for. No sources I've seen actually mention the one pictured here, but I vaguely remembered seeing their name on a plaque on one of the Sullivan's Gulch overpasses, so I went back recently to figure out which overpass it was, and take a few photos of it.

As you might imagine, there isn't much about this one on the interwebs, and frankly I suspect there aren't a lot of interesting facts about it out there to be discovered. It has no Bridgehunter page, but it does have a page on UglyBridges.com, which mentions it has a sufficiency rating of 58.5 out of 100 (which is better than a lot of bridges around town), and (for some reason) it isn't eligible for the National Register of Historic Places, despite its advanced age. I did find one vintage mention of the viaduct while it was in the planning stage, in which Waddell & Harrington advertised in Municipal Journal and Engineer, Vol. 28, seeking a contractor to do the construction work. The project was described as:

Furn. material and bldg. steel viaduct for city over Sullivan's Gulch, E. 12th st.: six 32-ft and two 64-ft deck plate girder spans on steel bents, concrete pedestals and abuts; 40-ft. roadway; two 10-ft. walks.