Is that another bridge in the archway of the second photo?
I grew up on Barrett Road. as kids, we knew how to get inside those little arches; the top one was so small you could not stand up straight. It was exciting. Story goes that the cyclone fencing went up after some guy fell off the bridge taking a shortcut home after drinking too much. I' m just glad we cot to explore it before then. Lots of graffiti, some filthy, some hilarious, and some both.
If you look at the aerial images in Google, there are actually three old RR bridges here.