Many African Americans have a lower body fat percentage, and men have a lower percentage than women. This makes it more difficult for them to float. As a result, if an untrained white and an untrained black person are dropped in the water, the untrained black person has a greater chance of drowning. I’m not sure this is the only reason, because women have a greater body-fat average than men, but nobody ever talks about the male fear of water. So I think there are other factors involved. It seems logical that swimming training and water sports in general are more accessible to historically middle-class families. Any untrained person is going to be afraid of water, no matter what their race.