Or more plainly a river and a dwarven watermill.
That's what I made anyway, both of them. I know it's a lot more practical to place a watermill on a world generated river since they have an ideal constant flow and constant water level, but I'm not into practical things.
So I made my own river by connecting two lakes that are on different z levels. It's far from an ideal river, as the only way to generate flow in a non ideal river is to have a different in waterlevel. So that rules out the constant waterlevel. No matter I can get it high enough under my watermill.
But even then it seems I can't get my dwarf made river to generate a constant flow. My first attempts sucked pretty hard where my watermill would only work half of the time, but my latest attempt allowed me to generate power for several minutes before a small hickup.
Now I don't mind a small interruption in power generation, however the watermill is connected to a millstone, and one tiny fraction of a second without power cancels every single task.
The idea was to make it an automatic grinder I didn't have to worry about, but right now I'm having to re set the tasks every 5 minutes.
I'll include a picture of my river and riverbed I made.
I should probably have included the part where the river stops in a waterfall, but most of it is on it.
So, is there anyone who can advice me on how to make this work? Any way to ensure a perfectly constant flow?