My dog has arthritis, is there any place I can take him swimming?

Like the topic says, my dog has arthritis and I'm looking for a place to take him swimming occasionally to help him take the pressure off of his joints. Ideally I'd like a pool or something as opposed to creek or trail, where he could be more relaxed. Maybe something I could book for a small amount of time if the price wasn't too high. Does anything like this exist in houston, preferably on the south side near clear lake?