Oliver doesn't seem to have much fear for water either. The bathroom routine mentioned below from others applies to him on a regular basis, he likes to lounge around inside the bathtub and bidet, he would like to get into the sink too but this we managed to block his way by putting a big laundry detergent bottle at the corner he uses for his entry there, as we haven't installed a cabinet yet for little objects and they hang about around the sink surface including my contact lens kit, which I wouldn't want him to play with!! (well, most of the time... sometimes he mananges to get in anyway somehow still!!
Insistent booger!!)
Sometimes he gets in the bathtub directly after going to toilet, leaving the sand inside the bathtub, it was gross so we tried to discourage him by turning on the water while he was inside. Instead of jumping out immediately, he just observed the running water calmly, letting his paws wet, then, when the tub got too wet to his liking, he sort of clambered out with all the tranquility. He also hangs about by my feet while I am doing the dishes or using the water at the kitchen/bathroom, and splashing of the water doesn't faze him either.
I keep wondering if he may like a little dip on a hot summer day!