The "privilege" to hold these baptisms rest with the wealthier JW who have houses with a swimming pool....
I wonder what they have done in Europe wher few people have pools on the property? I have never known a Witness with a home pool.
It would look very odd to do it at a public pool.
JWS baptism = cult initiation to make a vow of loyalty to the GB
(Executive Directors) of Watchtower Corporation /JWorg.