I don't know how old the OP's kids are...but in addition to the areas mentioned, there is a water cannon area in the Jurassic Park play area...where you can do battle with others, so that's another opportunity to get wet...but not for real little kids...
Oh, and the other place is the talking fountain in the Lost Continent....if it's warm, he can be very naughty and get guests very wet! It's pretty clear where the line is that people wanting to stay dry shouldn't cross too! This is a fun stop for young and older (and the jokes can be pretty funny for the adults), but sometimes the direct hit startles the little ones, so it's good to watch for awhile so they can see what they're wandering up to!
Can't think of anything else right now...but I agree with dressing with lightweight, fast drying clothes and waterproof shoes...so you can enjoy the fun and not be totally uncomfortable if you DO get really wet! I also will wear something like board shorts or lightweight nylon shorts with something waterproof underneath, like bikini bottoms and then a bathing suit top (tankini or bikini) with a loose fitting tank or sleeveless shirt over it.
If you're staying offsite and plan to have dinner, you can always rent a locker for the day for more appropriate attire.
I had it easy with 2 boys, they just wore their bathing suit all the time when they were little and we went to the parks!
Karen / MsDis