While technically it is a water feature, swimming is allowed. We recently got the girls new floaties and we were waiting for a warm day to try them out. They are still a little unsure about them. Elsie wouldn't sink down enough to really test it out. Alice tripped on the rocky bottom a few times, and while she floated so much she couldn't get her feet back on the ground, it certainly kept her head above water. A few more times with them and I'm sure they will get the hang of them.
When ever there are rocks, they must be thrown into the water.