Can You Swim in the Dead Sea? The Dead Sea is one of the saltiest bodies of water on Earth, with a salinity nearly ten times greater than the ocean. This extreme salt concentration makes the water much denser, which has a direct effect on buoyancy. Because Dead Sea water is so dense, it exerts a much larger buoyant force, allowing people to float effortlessly on the surface. However, that same buoyancy makes swimming awkward, since your body floats too high for your hands and feet to push effect