The Dead Sea is so salty that swimmers float on top and its shoreline keeps dropping

The Dead Sea sits in one of the lowest points on the surface of the planet, a landlocked lake bordered by Jordan, Israel, and the West Bank, and it has fascinated travelers for thousands of years for one particular reason: nobody can sink in it. The water is so dense with dissolved salts and minerals that swimmers bob on the surface almost like corks, unable to fully submerge no matter how hard they try. That same extreme chemistry has also made the lake one of the most closely watched bodies of water in the world, because it is shrinking at a pace that alarms hydrologists and threatens the communities and industries built along its shore.

Water Nearly Ten Times Saltier Than the Ocean

Ordinary seawater carries a salinity of roughly 3.5 percent, but the Dead Sea’s water measures closer to 34 percent dissolved salts and minerals, a concentration that the lake’s hydrological record places at nearly ten times that of the open ocean. That density is what allows a human body, which is only slightly denser than fresh water, to float almost effortlessly on the surface, with much of a swimmer’s torso and legs riding above the waterline. The mineral load includes unusually high concentrations of magnesium, potassium, and bromide, compounds far less common in ordinary seawater, which is dominated mostly by sodium chloride. Because the lake has no outlet, every mineral carried in by the Jordan River and smaller streams stays trapped, concentrating further every time water evaporates in the desert heat rather than draining away.

A Lake With No Way Out

The Dead Sea occupies the lowest point of the Jordan Rift Valley, sitting more than 1,400 feet below sea level, a depression so deep that the surrounding air pressure and heat drive intense evaporation year-round. Because no river carries water back out of the basin, the lake behaves like a giant evaporating pan, losing volume to the atmosphere while the salts and minerals dissolved in its water simply accumulate. This closed-basin geography is also what originally made the region famous for extracting minerals like potash and bromine, industries that today draw heavily on the very water that keeps the lake shrinking. The same processes that make the lake unusually salty also make it unusually sensitive to any reduction in the water flowing into it from upstream.

A Shoreline That Keeps Retreating

The lake’s surface level has been dropping by roughly a meter every year in recent decades, a rate that has pulled the shoreline back hundreds of yards in some areas and left former beachfront hotels and resorts stranded far from open water. Much of that decline traces back to upstream diversion of the Jordan River, the lake’s main historical source, for agriculture and drinking water across the region, combined with mineral extraction operations that pump lake water into evaporation ponds. The retreating water has also left behind an unstable landscape: as underground salt deposits that once sat beneath the lakebed dissolve when fresh groundwater reaches them, the ground above can suddenly collapse, opening sinkholes that have swallowed roads, farmland, and parts of tourist facilities. Thousands of these sinkholes have now been documented along the shrinking shoreline, transforming what was once solid beach into terrain that can no longer be safely used without careful survey.

Why the Water Feels So Different

Visitors who float in the Dead Sea often describe an odd, syrupy sensation against the skin, a direct result of the water’s mineral density rather than any illusion. The same salts that keep bodies buoyant also make the water sting sharply in cuts or in the eyes, and swallowing even a small amount can be dangerous, which is why lifeguards at Dead Sea beaches focus less on drowning than on making sure floating visitors do not accidentally roll onto their stomachs. The mineral-rich mud that collects along the shore has also been used for centuries in skin treatments, and the lake’s unusually still, heavy air, thick with evaporated minerals, has long drawn people seeking relief from certain skin and respiratory conditions.

A Race to Save a Shrinking Sea

Regional governments and international organizations have studied various plans to slow or reverse the decline, including proposals to pipe water in from the Red Sea hundreds of miles away, though cost, geopolitics, and environmental concerns have kept any large-scale project from moving forward. In the meantime, the lake continues to split visibly into a shrinking northern basin and an almost fully evaporated southern basin, the latter now sustained mostly by industrial evaporation ponds rather than natural inflow. Scientists tracking the decline warn that without a significant change in how much fresh water reaches the basin, the Dead Sea’s shoreline will keep retreating for the foreseeable future, reshaping a landscape that has drawn travelers since antiquity.

This article was produced with the assistance of AI and reviewed by Morning Overview editors.

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