Doesn’t seem like it’d be too much trouble in building one. I’ve actually been mulling the idea over in my mind as a potential alternate source of electricity generation. From what I understand, the best way to get the most energy production would be to have the water pour onto the wheel, versus having the wheel in a river/stream. That also means you do have a bit more control over the whole set up, as well as less potential damage should the river rise.
Check out this episode of Rough Science, they make a small one.
Canadian Patriot. Becoming self-sufficient.