Grist Mill or Engine Facility on the layout?

Well, I build models of grist mills, but, realistically, it would take a big turbine one, not the old classic water wheel ones, to fill enough cars to add much traffic to your road.  If it is just a scenic item, I'd want to tie it to the grain elevator, as the elevator's predecessor, which elevator might be loading  some cars, and, put in the engine service facility.  But, that hinges on what other industries you have to justify your railroad.  A two engine shed and a section of track with coal, sand, and dump area would service a branchline like you describe.  There were branches owned by

elevators that had one or two engines servicing them, and said elevator was the

reason for existence of the branch...

I might be able to put them on the same spur and keep the engine facility, but It would take up a lot more scenery area then I was hoping.  I also would have to re-route my river to go though my access hatch.  That would't be the end of the world I was just hoping not to have to do that.  

I will play around with it over the next few days and see what I like. 

Impressive layout, enjoying following your progress.