I like white water rides that get you wet because of the intense rapids or from a big drop (like Grizzly River Run at Disney California Adventure Park). Thunder Canyon relies on cannons and cheap waterfalls rather than its rapids, which are fairly tame. 5-Average.
Thunder Canyon is a hit and miss ride. On a day where you are hot and need something to cool you off this is the place to go but the sign that says YOU WILL GET WET ON THIS RIDE! is a myth because you don't always get hit by the waterfalls. So if you don't get lucky the first time then my advice is that if it a short line then try it again because it is very rare that a person goes on it twice in a day and doesn't get drenched.
There are barely any rapids on this ride. The soaking comes from the 5 waterfall effects, which you are going to pass through.
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