Unfortunately, you can't bring your own floaty-ring for your DD to the water parks. I've seen many kids with them at resort pools but apparently at the water parks it's a big no-no.
What we did when our DS was about that age was I hopped into the inner tube in the lazy river, and my husband passed the baby to me. DS sat on my lap all around the lazy river.
Either that, or you can just let her auntie carry her around the lazy river!
Only 2 more days Jennsky!