When I was a carman there, it was very common to see a lot of new and old road road power in and out of that yard. This was shortly before the Alameda Corridor was complete, and even after it was complete, Watson was still a convenient place to wye and/or fuel power via tank truck. Many trains now have their power hostled at the port itself, but Watson is still a key location for that part of the district. The power you shot may have been going over to Pasha for the slab train. Then, before the Ethanol rack was built, power was spotted adjacent to the 'main' line, roughly between the east and west switches of the wye, but on adjacent ready tracks.
I've only been back a few times since I craft transferred, and I know many of the jobs were re-advertised, so I don't know what this week's flavor is for power.

I always though the cemetary would be a good place to shoot from, but all my photos of Watson and vicinity never included that view- I like it; it does help to deliver the feeling of the Wilmington area...and it looks like you're still alive from risking your life shooting from PCH! Nice work!