Thanks for your encouraging thoughts, guys. The 45º angled wood I will add, good idea. Though it's a very slow moving stream, which will easily follow a 90º angle as well (this is Holland). This is based on a painting, so it's hard to see what is where exactly, a little logic needed to be added.
The streambed has some clumps of soil, which I didn't remove and due to the 0.25 render subdiv settings, they turn out 'ugly'. It can be improved greatly, and I might. Started out as a test of the model and I put some stuff in, you know how that goes.
The model can be improved in much detail as well, but after a while I've had enough of it.
Yes, and the wheels shouldn't be in the water, so it's a matter of precisely elevating ground and water. I added some flooring in the entrance and a wall, as I didn't like seeing into the hull of the building, but I forgot about the poor miller's foot.
The commission is to make a wall of 7m wide covering 4km of land, so these details will all be lost, I'm afraid.
Tried some water falling of the wood end, but threw it out. I have to put more work in that, some day.
EDIT: new version added