They are actually called liquid or water coasters. They are a cross between a roller coaster and a flume ride. Usually they start off as a roller coaster with coaster elements. The trains are usually single boats that run on coaster tracks instead of the flume troughs. The ending of a water coaster is much like a flume ride with a chute-the-chutes splah ending. I can only think of Priemere Rides, who makes them. There is one in Silver Dollar City amusement park called Buzzsaw Falls. I did see pictures of it on Thrillride.com on they're 2000 ride reviews. It looks like a fun ride. Hope that helps with your questions.
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Bill Yost a.k.a. THE BEASTmaster
www.geocities.com/byostie Can you take me higher? (CREED)