In breast augmentation, infections via the incision are potentially very serious because the implant might have to be removed if infection is established around the implant. Incisions can be protected in various ways and generally a bit of water splashing around such as a shower doesn’t stress the incision. The problem is soaking which weakens the seal of the incision and potentially allows bacteria in whether from the water or the body. Taking a submerged bath, spa/hot tubbing, and swimming all result in soaking and should be avoided for at least 8 weeks after surgery. It takes two weeks of uneventful healing for an incision to build up about 80% of its strength so err on the side of caution before soaking in any type of water.