ripples, airport way bridge, columbia slough

Since it's cold and icy outside right now, I thought I'd dig out something a little more summery to post. Here are a couple of Vine videos from the Columbia Slough Natural Area. At one point along the trail, a concrete bridge carries NE Airport Way over the Columbia Slough, and the trail goes underneath it. When the sun's at the right angle, ripples on the placid slough are reflected up onto the underside of the bridge, and voila.

Vanport Bridge

View Larger Map

The next Columbia Slough bridge on our little tour is the newest, other than the recently replaced Vancouver Ave. bridge. The Vanport Bridge is the long elevated structure right next to the Denver Ave. bridge that carries the MAX Yellow Line over the slough, Columbia Boulevard, the Union Pacific rail line, and a long stretch of industrial land north of the slough. Altogether it's nearly 4000 feet long. It's a fairly utilitarian-looking structure, so TriMet has tried a few things to, I guess, humanize it a little. First, they had the public vote on names for the bridge back in 2003, before the line opened, and "Vanport Bridge" was the overwhelming winner of that contest. (Not to be confused with an entirely different Vanport Bridge in Pennsylvania, which carries Interstate 376 over the Ohio River somewhere near Pittsburgh.)

TriMet also spent a decent chunk of the MAX line's One Percent for Art money on public art to decorate the bridge. From TriMet's Yellow Line art guide:

Spencer T. Houser and Chris Rizzo present two approaches to the nearly 4,000-foot light rail bridge.

• Ninety flaming comets inspired by the car culture of the '50s blaze northward from Kenton.
• Blue metal panels on the north end of the bridge allude to the Columbia River.

Despite the art it hasn't yet become a beloved local landmark, so there isn't a lot of stuff about it out on the net. I did find a few mentions of it from TriMet and various engineering firms that had a hand in its construction:

• It's mentioned in TriMet's "DBE & Workforce Story" (where "DBE" stands for "disadvantaged business enterprise") explaining how the MAX line construction benefited minority workers & businesses.
• The engineering firm responsible for design of this segment of the MAX line includes it in a PDF of their recent or high profile bridge projects.
• The FE Ward engineering firm both designed and built the bridge.
• Info from another engineering firm that had a hand in the project.

Denver Ave. Bridge

[View Larger Map]

The next Columbia Slough bridge on our little tour is the one that carries N. Denver Ave. over the slough. Like the MLK and N. Portland Road bridges, this is an ODOT-owned bridge, since this stretch of Denver Ave. doubles as a chunk of highway OR 99W. At one time, 99W (a.k.a. the "West Side Highway") continued through downtown Portland, from SW Barbur to Front Avenue, then along Harbor Drive to the Steel Bridge, then up Interstate Avenue to Kenton, where it jogged over to become Denver Avenue, and then headed across the Columbia Slough north to the Interstate Bridge. Most of that stretch is no longer a state highway, but the stretch of Denver Ave. north of Argyle St. still is for some reason.

The Portland stretch of 99W was a late addition to the state highway system. At the time the Interstate Bridge went in, there was a great deal of infighting about which street would be the main approach to the bridge: Union Avenue (now MLK) or Vancouver Avenue, which Union Ave. finally won after a few years of rival booster clubs duking it out. Interstate (then known as Patton Avenue) wasn't in the running, because a steep bluff at the south end meant it didn't actually connect directly to downtown back then. It was a major local street, and was platted out as a wide street in case it became a major arterial later (which was a huge help when the MAX Yellow Line went in), but in 1916 it dead ended somewhere around today's Overlook Park. So a small wooden bridge was built, giving local traffic access to the Interstate Bridge.

A decade later, a major roadcut project finally connected Patton Avenue to the Steel Bridge and downtown Portland, and the widened street was rededicated as Interstate Avenue in September 1928, though a lot of references I've seen give 1929 as the actual project completion date. The bridge over the Columbia Slough was reconstructed at that point to handle the additional traffic. The Oregonian's "Year in Review" article on Jan 1. 1930 portrayed the Interstate Ave. project as one of the year's major news stories. A 1947 aerial photo shows the bridge here, along with an area of commercial development along the Kenton stretch of Interstate, but you can see that parts of the surrounding area were still semi-rural even then. A couple of interesting Cafe Unknown posts have more about the history of Interstate Avenue, with all its ups and downs, from potholed neighborhood street to neon wonderland, to blighted backwater after I-5 opened, and now to a rapidly gentrifying neighborhood with its own MAX line.

ODOT's 2012 bridge condition report says the slough bridge dates to 1916, while the adjacent viaduct over Columbia Blvd and the Union Pacific railroad is circa 1929. So it's possible there was a surface level intersection and railroad crossing here until the bridge upgrade project, in which case the original slough bridge was probably lower than the current one. That's my guess, anyway.

The 2013 state historic bridge inventory describes the bridge and viaduct:

In the late 1920s, increased traffic on the West Side Highway led to a major revision in how the highway approached the Interstate Bridge, then the only Portland area crossing into Washington State. Prior to this redesignation, the West Side Highway ended at downtown Portland, with only the Pacific Highway continuing over the bridge. These new bridges were designed to match those on the Pacific Highway, and continued to be a major part of the approach until the construction of I-5. They both feature a unique baluster railing, which is now mostly hidden behind protective wooden paneling.

Unfortunately I don't think you can see the unique bridge railing very well in any of these photos. The inventory PDF has a better photo, showing it really doesn't look all that different from other ODOT bridges of that era. The inventory goes on to mention that the slough bridge consists of "Three 78-ft steel girder and floorbeam system spans with reinforced concrete deck girder approach spans", while the viaduct is "Thirteen 71-ft reinforced concrete girder and floorbeam system spans with curved haunches.. ODOT researched the history of the Denver Ave viaduct over the railroad for the MAX Yellow Line project. The study determined it was ineligible for the National Register of Historic Places, and mentioned the slough bridge as similarly utilitarian & ineligible. The city's historical research for the Vancouver Ave. bridge replacement also mentions the Denver Ave. bridge briefly, but doesn't have much to say about it.

No discussion I've seen of the bridge mentions who designed it, and they usually do if a bridge is by someone well-known or historically important. The Union Ave./MLK, N. Portland Road, BNSF railroad, and (original) Vancouver Ave. bridges turned out to be minor designs by rather famous bridge engineers, but as far as I can tell that's not the case here. Perhaps as a result, it doesn't have a BridgeHunter or Structurae page of its own, but it does at least have an UglyBriges.com entry. That page tells us the bridge has an ODOT sufficiency rating of 51.7 out of 100 (as of April 2013), and it's described as being in "fair" condition and "functionally obsolete". It received an underwater inspection in 2011, which noted that the underwater portion of the bridge pilings are not entirely steel and concrete, which is a little surprising: "The part of this structure across the slough consists of 3 steel girder spans of 78 ft. each. Each pier is supported on two concrete columns with a webwall in between, that are supported by two individual concrete footings founded on untreated timber piling."

An upcoming ODOT project will redesign the intersection of Denver Ave. & Schmeer Road, directly north of the bridge. At present the north end of the bridge crosses an underpass that routes southbound traffic onto Schmeer Rd. The redesign will move the intersection north, and turn the underpass into a stretch of the Columbia Slough Trail instead. In Spring 2015 they'll also start work on the bridge and viaduct, resurfacing them and replacing the current bridge railings and adding crash barriers. Schematics of the new design indicate there will be a crash barrier separating the sidewalk from street traffic, and the redesigned bridge will include separate bike lanes, which it doesn't currently have. It will still only have a sidewalk on one side of the bridge, I suppose because extending the bridge out to add one on the other side would be too expensive. Still, it seems like a positive step, in an area that's only going to have more bike and pedestrian traffic as the Columbia Slough Trail keeps being extended.

Inverness Force Main Bridge

[View Larger Map]

The next Columbia Slough bridge on our mini-tour is the newest, other than the rebuilt Vancouver Ave. bridge. The Peninsula Crossing Trail continues north after the Portsmouth Cut area, and crosses the Columbia Slough on a new-ish bike/pedestrian bridge, just east of the city's ginormous Columbia Wastewater Treatment Plant. Several sources (including the Google map above) insist the bridge and the bit of trail south of it are part of the Columbia Slough Trail, which intersects the Peninsula Crossing Trail just north of the bridge. The Intertwine trail map says it is, a Metro map about the ongoing Columbia Slough Trail project says it isn't. The slough trail is an east-west trail along the north bank of the slough, running a few miles through N/NE Portland, while the crossing trail is a roughly north-south route that vaguely parallels the BNSF railroad across the N. Portland peninsula. The bridge is clearly part of the latter route, not that that's going to stop anyone from making new wrong maps in the future. The map error is out there now, and map errors tend to be strongly self-propagating once they're out in the wild.

Anyway, when I walked across the bridge, I thought it seemed a lot more solid and heavy duty than was strictly needed for a bike and pedestrian bridge. I assumed that was so the occasional maintenance or emergency vehicle could use it too. Then I bumped into an old planning document from 1996 that explained the bridge's hidden secret. It turns out that in the early 90s the city's Bureau of Environmental Services wanted to build a bridge over the slough for the Inverness Force Main, a shiny new sewer pipeline (though maybe "shiny" is the wrong word here), and they figured they might as well put a bike/pedestrian walkway on top, concealing the pipe while they were at it. (Though it seems like they continued calling it the Inverness Force Main bridge instead of naming it after either of the trails.) It's not just any old sewer pipe, either, but a 30 inch main carrying pressurized raw sewage. As you might imagine, it was kind of a bad deal when the pipe under bridge sprang a leak back in February 2014. The public was advised to avoid contact with the slough, which generally speaking is what people do anyway.

I-5 Columbia Slough Bridge

View Larger Map

The next Columbia Slough bridge on our mini-tour is the I-5 Columbia Slough Bridge. When highway traffic reports use the dreaded phrase "northbound traffic backed up past the slough bridge", this is the bridge they're talking about. I haven't actually paid attention to traffic reports in a while, since I live in downtown Portland and walk to work. It's possible this phrase is less common than it once was; the bridge was widened in 2008-2010 as part of ODOT's I-5 Delta Park project. The project removed a notorious traffic bottleneck for Clark County commuters by widening this stretch of freeway from two lanes to three in each direction. Somehow they managed to do this without shaving off parts of the adjacent Columbian Cemetery just south of the bridge. The project's final "Revised Environmental Assessment and Finding of No Significant Impact" included a few provisions for coexisting with the cemetery, such as not running pile drivers during funerals.

Even the widened freeway is still puny by the standards of nearly any other city. The Oregon side of the metro area has a general policy of freeways having no more than three traffic lanes per direction, so this is as big as I-5 is likely to get barring an unlikely tectonic shift in local attitudes toward cars. As predicted, the traffic bottleneck simply shifted south to another section of two lane freeway around the Rose Quarter / convention center area. There have been suggestions about widening the freeway there too, and potentially capping it and putting parks or buildings on top. That would probably just push the bottleneck somewhere else again. But I do generally like the idea of capping freeways and hiding the ugliness away underground, so maybe there would be an upside to the idea. My understanding is that the widening was also supposed to be a prerequisite to the now-abandoned Columbia River Crossing, which would have been a ginormous replacement for the current Interstate Bridge.

Anyway, these photos were taken from the new stretch of Columbia Slough Trail that opened in early 2014, so you can see what the bridge looks like from the side and underneath, in case you were curious. It's sort of a utilitarian, unmemorable bridge, but it's interesting that they blended the expansion with the existing bridge so it isn't immediately obvious that it was widened. If you look closely at the bridge supports you can see a line between older & newer concrete where the outside lanes were added.

The library's Oregonian database indicates that ODOT proposed the bridge in May 1962, as part of what was then called the "Minnesota Freeway" project. (I-5 south of downtown was called the "Baldock Freeway" and I-405 was sometimes the "West Hills Freeway" and other times the "Foothills Freeway". All of these names have long since fallen out of use.) A photo spread in March 1964 shows the bridge under construction, and another photo in July of that year shows the bridge nearing completion. By 1981 (when the bridge was only 17 years old), Multnomah County and ODOT were already wringing their hands about it, but at the time they couldn't afford to do anything about it. It was already over capacity in 1981, but they went around in circles for another 25 years before figuring out how to make it happen. I suppose impatient people don't last long in the civil engineering business.

Union Pacific Columbia Slough Bridge

[View Larger Map]

The next Columbia Slough bridge on our mini-tour is the Union Pacific railroad bridge, which crosses the slough and Wright Island just east of the new pedestrian bridge. I can't find much in the way of information to share about this one: How old it is, who designed it, the usual factoids. That's annoying but not uncommon with obscure railroad bridges. Looking at it, you can see the stubs of old pilings underneath the bridge, suggesting the current one replaced an earlier wooden trestle-type bridge. Not sure I would hazard a guess as to how old the current bridge is; a 2003 ODOT study on improving local rail access suggested replacing it with a new, higher bridge, but I don't know whether this was ever implemented. It looks older than 2003, though, or at least the portion south of the island does. The northern side looks like it might be newer, but it's hard to tell, and (as I said) I have no concrete information to pass along.

In lieu of that, all we've got are a few Panoramio photos, and photos on railfan sites (and they're mostly interested in bridges as places to photograph trains.) One such site points out that this train line is just north of a major rail junction, as well as the Union Pacific tunnel under North Portland, so apparently this area is kind of a big deal if you're into trains.

N. Portland Road Bridge

View Larger Map

Our next Columbia Slough bridge is the one carrying N. Portland Road; in the photos above, it's the bridge hidden behind the BNSF railroad bridge. I could have gotten closer to take better photos, but neither it nor the railroad bridge looked very interesting so I didn't make the detour. In retrospect I probably ought to have made the trip, since it does have a degree of historical significance. N. Portland Road is actually a state highway, OR 120, although people don't realize this because the state's never gotten around to putting up highway signs. It was built back in the 1930s to connect North Portland to the long-gone stockyards and meatpacking district. One alternate name for the road that's occasionally been used is "Swift Highway", named not for the speed limit, but for the old Swift Meat Packing Company, which built the stockyards and ran Kenton as a company town in the early 20th Century.

As a state highway, the state was responsible for building bridges on it, and for much of the 1930s tha was Conde McCullough's job. He's best known as the designer of fancy bridges along US 101 on the Oregon Coast, but as the state's chief bridge engineer even the most mundane bridges were part of his bailiwick. Obviously he wasn't the state's only bridge engineer, but he tends to get credit for anything the state built during his tenure, similar to Steve Jobs getting sole credit for various Apple products. In this case, McCullough at least invented the type of bridge used here; the department ended up building 158 bridges of this type around the state, so presumably the implementation work for each was farmed out to the department's junior engineers. The wood/concrete composite design was intended to be an affordable way to build smaller bridges, with the important side benefit of throwing some business to the state's struggling timber industry during the Depression. A historical review of the similar (and since-replaced) Vancouver Ave. bridge has a blurb about this one:

The N Portland Road bridge (formerly “Swift secondary highway”), was constructed prior to the subject bridge in 1934 using a similar composite type (Myers 1935:4). The concrete pile bent design varied slightly from the subject bridge by incorporating pointed Gothic-style arch openings. The Swift Highway connected North Portland to the Portland Union stockyards. The bridge retains less integrity than the subject bridge. Many of the understructure wood piles have steel column replacements and the handrail’s wood intermediate posts were removed and replaced by an adjacent modern rail.

Some of the replacement work happened in 2007. The bridge is a major trucking route, so it makes sense that 1930s wood beams would wear out after bearing decades of modern semi trucks. The state transferred much of the highway to city jurisdiction in 2005; from the included map in the transfer deal, it appears the deal transferred everything except the bridge (which it refers to as "Columbia Slough Bridge No. 01726"), with the agreement specifying "Said bridge shall be transferred at such time that said bridge is replaced with a bridge meeting AASHTO bridge design standards", AASHTO being the American Association of State Highway and Transportation Officials. In other words, everyone agrees the bridge needs replacing, and the city prefers that to be the state's problem, paid for from the state's budget.

Vancouver Ave. Bridge

View Larger Map

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?

BNSF Columbia Slough Bridge

View Larger Map

The next Columbia Slough bridge on the agenda is the one carrying the BNSF railroad. This is the same rail line that crosses the Columbia on the Vancouver & Oregon Slough railroad bridges, and continues on through the Portsmouth Cut (beneath a set of railroad-owned road bridges), and then across the Willamette on Bridge 5.1. Like all of the aforementioned bridges, the one over the slough was designed by Ralph Modjeski (who also designed downtown Portland's Broadway Bridge).

This is the smallest and undoubtedly the least interesting of the BNSF Modjeski bridges. Frankly there's nothing interesting about it other than who designed it, and it's hard to imagine that he actually spent a lot of time on this one. There wasn't even anything in the Oregonian database about it, as far as I can tell. But one of the constant guiding principles at this humble blog is that some things are worth doing just for the sake of completeness, and this bridge completes the set of Portland Modjeski bridges. As far as I know. One upside of this sake-of-completeness thing is that I end up having a top search ranking for all sorts of curious and obscure things. Which would be great, if anyone was ever bored enough to actually Google them.

MLK Columbia Slough Bridge

View Larger Map

For several years now, one of this humble blog's ongoing projects has involved bridges. I started out with Portland-area Willamette River bridges, and once I'd done posts about those I ended up doing bridges on the Columbia, Clackamas, and Sandy Rivers too. I've also done bridges in the Columbia Gorge (and there may still be a few of those that I've missed), as well as a bunch of bridges in Cleveland from a trip there a few years ago. I also recently found some lists of Portland-area bridges that local governments believe are historically significant, so I've covered a couple of those too. A few months ago it occurred to me that there were a decent number of bridges on the Columbia Slough, in N/NE Portland, and I could visit a lot of them just by walking the Columbia Slough Trail. None of them are really visually stunning, but some at least have a bit of historical significance. Case in point, the bridge shown above, which carries MLK (a.k.a. state highway OR-99E) over the Columbia Slough. Its Bridgehunter page describes it:

The Columbia Slough Bridge on OR 99E was constructed in 1916 as part of the Interstate Bridge project. The bridge features built-up steel plate girder main spans and the same decorative steel railing found on the 1917 Interstate Bridge over the Columbia River. The bridge was likely designed by consulting firm of Waddell and Harrington just like the Interstate Bridge located just a short distance to the north.

The 304-foot original portion of the bridge features four steel plate girder spans with two main spans of 77.3-feet and two side spans of 76.2-feet. In 1951 the original 44-foot wide structure was widened to 58-feet by the Oregon State Highway Department to accommodate another traffic lane. The new portion of the bridge has a different span layout featuring two 140-foot plate girder mains spans and reinforced concrete approach spans at each end of the structure. The total length of the widened portion of the bridge is 362.5-feet.

In other words, this bridge was a minor project by a very famous bridge design firm. They were the same company behind the Interstate Bridge (obviously), as well as the Hawthorne and Steel Bridges in downtown Portland, the Union St. Bridge in Salem, and the Columbia River Highway bridge over the Sandy River in Troutdale. Oh, and the 12th Ave. Viaduct over Sullivan's Gulch / I-84, near Lloyd Center, which counts as another minor project.

A July 1916 Oregonian article on the near-complete Interstate Bridge mentions the slough span briefly as a remaining to-do item, due to problems with the initial construction done there:

When the water falls sufficiently, a pier will be erected in Columbia Slough to replace the one destroyed by the shifting of the bottom of the slough on account of the tremendous pressure of the big fill at that point. Not until this pier is built can the girder spans across Columbia Slough be placed.

Other than a few traffic accidents, the bridge apparently hasn't been newsworthy since its construction. I suppose if they ever get around to replacing the current Interstate Bridge, this little bridge would be left around as the last surviving piece of the original project. At that point the bridge might come be seen as an interesting historic artifact. But given the recent cancellation of the Columbia River Crossing project, that day isn't likely to come anytime soon.