[daschwa]

Problem is, when I was doing my lifeguard training they showed us / told us how the surface of the water distorted swimmers and who / what is below the surface. A towel or swim toy can look like a person once fully submerged. (it is required to wear polarized sunglasses in chair) You would need cameras under the water, focused on the bottom of the pool to be of any use I imagine. As a lifeguard, our main objective is scanning for signs of struggle yes, but also to be checking for bodies below the surface. With unresponsive victims, every second counts.