Our tour of Portsmouth Cut bridges continues with the Lombard. St. Bridge, the next one north from the Willamette Boulevard bridge. It's a similar deck truss design and has the usual Bridgehunter and UglyBridges.com pages, for your bridge-geekery needs (if you have bridge-geekery needs). The city's 2002 St. Johns/Lombard Plan calls out this bridge (but not the others) as having high historical significance. The brief blurb about it just describes its construction and doesn't explain what's so special about it. The Portsmouth Cut itself only managed rank III, though it merited a longer description:
Railroad Cut 6929 N. Carey Boulevard The Portsmouth Cut is an approximately 6,600 foot long cut in the bluffs at St. Johns through which run two mainline and auxiliary railroad track.
Significance: Transportation. The railroad bridges, cuts, and tunnels of North Portland, all built circa 1907, were the result of competition between the principals of two major railroads: James J. Hill (Great Northern,Northern Pacific, and Spokane, Portland, and Seattle (SPSRR)) and E. H. Harriman (Union Pacific and Southern Pacific). The Great Northern did not have direct access to Portland, leading Hill to build the SPSRR to provide independent access to Portland. He built the bridge over the Willamette River, the cut through the North Portland Peninsula, and the steel bridges over the Oregon Slough and the Columbia River. On the other hand, Harriman wanted direct access to Seattle for his Union Pacific line, which passed through Portland. Around 1910, the railroads settled their differences and the Union Pacific built a tunnel through the peninsula to connect with the SPSRR at what is now called North Portland Junction.
The Lombard St. bridge has the same messy ownership & maintenance situation as the Willamette Blvd. bridge, and it seems to be in more or less the same state of repair. There's an added twist here in that Lombard doubles as US 30, an Oregon state highway, so the state transportation department is responsible for the road. The state's role regarding this bridge (if it has one) is unclear; at any rate they don't appear to have any more leverage over the railroad than the city does.
For a bridge the city thinks is an iconic landmark, I can't find much in the way of interesting links to share about it. What's more, a lot of the search results that do come up (like this city trail alignment plan) refer to an entirely different bridge, which carries Lombard over the Columbia Slough up near Kelley Point Park.
I did find an account of a 2012 protest on the bridge, in which environmental activists campaigned against coal trains running through the Portsmouth Cut. That's obviously a concern, since the cut borders residential neighborhoods on both sides. But as dirty and flammable as coal trains are, the latest controversy involves oil trains. The current North Dakota oil boom came with an infrastructure problem, in that there was no existing pipeline to get the oil out of North Dakota, and building a new one would be expensive and involve a great deal of bureaucracy and controversy. So instead the oil companies quietly began shipping oil by rail, and they aggressively lobbied state governments to keep all information about the trains private and confidential. I suppose they figured that in the wake of the Lac-Mégantic oil train disaster, running hundreds of oil tank cars through residential neighborhoods might be a tad... controversial. Some of the North Dakota oil is destined for export -- yes, the USA is actually exporting oil now -- and this oil travels by rail to an export terminal at Port Westward, OR, near Clatskanie. I didn't realize there even was an oil export terminal there; it turns out that it used to be an ethanol plant, built with public subsidies no less, and they're somehow reusing the environmental permits the plant received when it made ethanol. The route to Clatskanie takes oil trains right through the Portsmouth Cut, as many as three trains per week. The Oregonian dug this up in a rare (for them) bit of investigative journalism, despite the state's effort to shroud the whole business in total secrecy. This may seem surprising in a state with such a liberal, tree-hugging reputation, but in general the state government (and DEQ in particular) have always sided with corporations over public health and safety, at least when they think nobody's looking.