If there's water... they will come.
I don't think the ducks are more fond of one pool than another. They don't care if it's in the shape of a giant guitar, bowling pin or fishing hole. If you aren't concerned with swimming in a lake or ocean, there's really no reason to be concerned with swimming with a duck. With the high chlorine levels, the pools are much cleaner than any natural body of water.
If you see a duck doing it's business, move to another section of the pool. Just make sure there isn't a child, or adult, taking care of their own business!