My Application
I was originally going to try and put the water source on the track coming up from my helix structure to the top level,..figuring the steam engines would need some water after that climb. But I didn't have room for it over there.
So here is where I thought I would put it,...at the intersection of my loop of track that goes into that upper helix loop,...and the alternative loop I've provided for the trains to do another loop around the interior of the room.