The Dead Sea is so salty that you cannot sink beneath its surface

The Dead Sea is one of the strangest bodies of water on the planet, a landlocked lake wedged between Israel, the West Bank, and Jordan at the lowest point on any continent. Visitors who wade in quickly discover that the water refuses to let them sink, holding the human body high on the surface as if it were resting on a firm mattress. The sensation is so unusual that it has made the lake one of the most photographed natural attractions in the Middle East, a place where the ordinary rules of swimming simply do not apply.

A lake with almost ten times the ocean’s salt

The reason lies in the water’s extraordinary mineral content. Ordinary seawater carries a salinity of around 3.5 percent, but the Dead Sea holds roughly 30 percent or more dissolved salts, making it close to ten times as salty as the open ocean and one of the saltiest large bodies of water anywhere.

All that dissolved material makes the brine far heavier than fresh or ordinary sea water. As Encyclopaedia Britannica describes, the lake sits in a deep rift where water flows in but has no outlet, so evaporation under the intense desert sun concentrates the minerals left behind, driving the salinity ever higher over time.

The physics that keeps a swimmer afloat

Buoyancy is governed by density. An object floats when it is lighter than the volume of liquid it pushes aside, and the Dead Sea’s brine is so dense that it can weigh roughly a quarter more than the same volume of a human body. A bather therefore needs to displace only a small part of the body to be held up, and the rest naturally rides above the waterline.

The practical result is that people bob at the surface without effort, often photographed reclining on their backs while reading. Swimming in the usual sense is awkward, because the legs and torso are pushed upward and the thick, oily-feeling water resists ordinary strokes. Bathers are also warned to keep the water away from the eyes and mouth, since the concentrated brine stings badly and tastes intensely bitter rather than merely salty.

Why the salt makes it hostile to life

The same chemistry that supports floating bathers makes the lake nearly lifeless, which is the origin of its grim name. Fish and typical aquatic plants cannot survive in water this saline, and only specialized microbes and salt-tolerant microorganisms manage to persist in the harsh brine.

The high mineral concentration also gives the shoreline its distinctive crust of white salt formations, and the dense water leaves a slick residue on the skin. For centuries the lake’s minerals and muds have been prized for cosmetic and therapeutic uses, drawing spa-goers to its shores.

Prized minerals and a place in history

The Dead Sea has drawn people to its shores for thousands of years, appearing in ancient texts and drawing figures from antiquity who valued its minerals and reputed healing qualities. Its waters and black muds are rich in magnesium, potassium, calcium, and bromine, elements long linked to skincare and to the treatment of certain skin conditions.

That reputation has given rise to a thriving industry. Resorts and clinics along the coast market mineral baths and mud treatments, while companies extract potash and other compounds from the brine for use in fertilizers and cosmetics, turning the lake’s punishing chemistry into a significant economic resource for the surrounding region.

Sinkholes along a retreating shore

As the water level falls, the receding shoreline has produced a hazard of its own. Fresh groundwater flowing toward the shrinking lake dissolves layers of salt buried in the ground, hollowing out cavities that eventually collapse and open sinkholes without warning.

Thousands of these pits have appeared along the western and eastern edges of the lake, swallowing sections of road, farmland, and abandoned buildings. The sinkholes have forced the closure of some beaches and access points, a visible consequence of the lake’s decline that adds urgency to efforts to stabilize it.

A shrinking sea under strain

The Dead Sea is not static. Its surface has been dropping for decades as water is diverted from the Jordan River, its main source, for agriculture and drinking supplies across the region. According to NASA, satellite observations track how the lake continues to recede and grow saltier, exposing former lakebed and concentrating its minerals further with each passing year.

Engineers and governments have floated proposals to replenish the lake with water piped from the Red Sea, but no large project has yet reversed the decline. For now, the Dead Sea remains both a natural wonder and a warning, its buoyant waters lower and more concentrated with each passing year.

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

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