Is a water birth safe for both mother and child?
My wife and I researched this a lot before having our first child. Here's what we came up with.
There are two kinds of water birth, the kind you do in your own home and the kind that can be done in the hospital. We opted to not do any home birth because in the event something goes wrong we wanted to be in the hospital, where doctors were present. In an emergency situation every second a child goes without oxygen could be critical, meaning that should something go wrong with your home birth you need to make a call to the ambulance and this further delays the time that doctors can help the child.
Then there are water births done in hospitals. In general these are very safe and you are close to the NICU should you child need intesive care. Our second child had to go to the NICU after she was born. Thankfully it wasn't a breathing issue, but getting her there early was very important. They also ran tests that we would not have been doing had we been at home.
Ultimately we didn't do a water birth at all because the hospital where our doctor delivered did not offer this as an option. We felt that giving birth outside of the hospital was out of the question and my wife wanted to be where her doctor practiced so we didn't do the water birth.
Final answer is water birth is safe when done in a hospital environment where you can be close to emergency care should you or your child need it. Many things can go wrong in childbirth, it isn't necessarily common, but its not so uncommon that you should be cavalier about it.