It all depends on the specific swimming hole. If it's popular enough to find with a Google search, it's probably gonna be either gross or crowded. Definitely try a state park with swimming, or if you know of any "locals only" spots, they would be better. One word of caution, my daughter got giardia from playing in the creek. Kinda unavoidable when you're playing in streams all the time, but just be on the lookout afterwards and try not to swallow the water.