some hospitals even have jacuzzi tubs. you just have to request a room that has one. my hospital does. might be a safer option if you want to be in the tub.
Have yu considered just having a water birth?
Bath water should never be hotter than 100 F. You can just refuse an epidural, and make your wishes known to the doctors. If they know its what you want (and your family) they'll make sure you don't get one.