This video gives you a look at the water intake upstream.
Have a look at the next page for photos of a Harris Turbine’s insides. I grabbed these photos from the ebay auction of a Harris Turbine. The last time I looked at the auction on ebay the turbine was under $150!! That’s cheap, no?
There’s a full .pdf of this turbine make-a-watt’s resources page if you want to know everything.