So, since it's clearly visible in historic aerial imagery, they must have removed the structure and filled it in.
https://www.newspapers.com/newspage/17565774/ Shows a picture of them excavating at the new bridge, which, by virtue of being larger, would've provided more than enough fill to fill in the gap.
I walked the north side of the RR embankment from the creek east to the driveway. The brush was thin enough to see the ground and I saw no trace of anything that hinted of a 60' arch.
Limit street used to continue straight to the west rather than curve north to miss the RR.
http://bridgehunter.com/ks/leavenworth/bh54987/
I have walked the area in summer and didn't see where the road went under the RR grade but foliage can hide things.
Certainly not the same bridge type listed here, but this beautiful double arch most likely same bridge....locations identical
Hard to say if this one still exists. There's one thought, which says if it did, someone would have noticed it by now. Then again, it's extremely overgrown. I doubt it's any less than partially filled in if it does still exist however.
April 28 1977
The Leavenworth Times