[Disneyfever]

I just read this tidbit in one of the above links. My husband guessed it when we went on Splash Mountain over and over:

Outside, when every third log boat comes down the big drop into the briar patch, an auxiliary water cannon shoots off a charge of water that soaks folks standing on the bridge to Big Thunder Mountain. (This has been shut off some of the time including during cold spells and drought spells.)