Natural water birth

I have a question. I am wanting to do a natural water birth, but I'm afraid to do it at home and my hospital doesn't offer it. Would I be able to talk to my OB and see if we could bring in a birthing tub or would it most likely be a no since its not offered at the hospital? Might be a dumb question and I'm going to ask my OB, I just wanted moms who have done this before to help with some advice.