I recently acquired a single track lift bridge (From Custom Model Builders) and need to find a plausible location to put it on the Ultimate P&A Layout (it will also be used as a part of the Interim P&A Layout but as the name implies, it's an interim plan, and will not follow anything particular on the map, but the modules built for it will be relocated as part of the Ultimate P&A Layout). I was wondering, since I'm tweaking history a bit by
having the P&A acquire the right of way along the east bank of the Allegheny River (instead of the PRR acquiring it after the Allegheny Valley Rwy goes bankrupt) amd the 43rd Street yard becomes the southwest terminus of the P&A and interchanges with the PRR, B&O, WM, P&WV, and P&LE that the P&A build
it's own bridge to cross the Yough. River to connect with the P&LE and the B&O as well as to reach a steel mill on the west side of the Yough River that the owners of the P&A had a partial financial interest in, which by
1953 (the time I'm modeling) had become defunct (so I don't have to concern myself about modeling it). Because of limited approaches to cross the river within the city, the P&A did not have sufficient space to build a bridge high enough to clear the traffic below, requiring a lift bridge.

Is this sort of "back story" plausible and sufficient to use this kind of bridge in this area?

If this is not plausible, then I am at a loss, because the only other possible solution is to have some kind of ship canal come off lake Erie that the mainline needs to cross over, except why would there be a ship canal
that needed to go far enough inland from the lake that the railroad would have to cross over at that point. This is where proto-freelancing is especially getting me into trouble since it "allows" me to purchase structures that I love to have, and then I have to go find a justification for it because I am concerned about having a plausible layout and not fantasy land. :-\  Yes Rule #1 is it's my model railroad and I can do whatever I want with it, but unfortuantely for me, i'm trying to set plausible benchmarks so that when others see it, especially those who  now Pittburgh and the railroads that ran through it, it doesn't seem to be fantasy land.

Thanks for any feedback!

Ken L.
Pennsylvania & Allegheny RR, circa 1953