I'm with B-david. A water-turbine sounds like a debris catching nightmare. Since at one time the world ran on hydro-power I'm sure every conceiveable mechanical means of harnessing streampower has been tried, but you might have to go back to 1800's literature to research it. There's a good reason why we don't do it on a small scale much anymore
. If you do actually try this, let us know how it turns out!
