This MWF looks like it could be a former SSW bulkhead flatcar. On a related note, I saw a Cotton Belt bulkhead flatcar carrying steel plates that had its bulkheads chopped like the one in the link.
I notice that it is sitting in water. I would think that that would not be a good thing.
Somewhere on that wheel flat should be stencilled the SP classification of the car, which would lead you to the series of origin. I suspect that the bulkheads, or what’s left of them, are a good thing on these cars Around here it appears that SP wheelset cars, with or without bulkheads, have become the wheelset car of choice for the UP. I don’t think many CNW wheelset flats are left, and I suspect that the ranks of short UP flats have been decimated as well. MP had some purpose-built wheelset cars (look like coil steel cars without the covers) which may still be around. _______________________________________________________________________ Cutting down the bulkheads for use in steel sheet transport seems logical–without the weight of the too-tall portion, perhaps an extra plate or two could be carried on the same car, yet you still have the protection against excessive shifting of the load. There have been a number of flats built this way (with short bulkheads) since 2000.