But his preferred solution is more radical and controversial: abandonment of much of Israel and Jordan’s export-oriented, and in his view unsustainable, agriculture to start restoring the waters of the river Jordan, and through it the Dead Sea, again. Anything less is unacceptable.” Mr Bromberg and his colleagues in Ramallah and Amman want the Dead Sea declared a Unesco World Heritage Site, because the parties would first have to show they can manage the crisis. He says: “We are not trying to rule out Red-to-Dead, only to make sure all the options are considered We need a truly independent study. With his Palestinian and Jordanian FoE directors, he has been agitating – with limited success – for the World Bank to widen its terms of reference.

He is also worries about potential damage to coral reefs in the Gulf of Aqaba from such wholesale extraction, and the potential of salt water to contaminate freshwater supplies if the conduit is damaged in what is an earthquake zone. Mr Bromberg has serious reservations about its ability to solve the Dead Sea crisis. He says the mix of sea water from Aqaba with the Dead Sea could trigger an adverse chemical reaction, creating gypsum, algae and even toxic gases. As with every large infrastructure project in the world, not everyone is sold on the idea.

“At the same time, it would be able to provide a great deal of water to the Jordan Valley which would allow very scarce resources to be freed elsewhere,” Mr Stevens says. The total project would cost a perhaps a daunting $5bn, but John Stevens, a banker helping to put together a British consortium, believes a basic $500m Red-to-Dead link could be funded by private sector investors buying land then selling it after it is irrigated by desalinated water, for development of a large new trans-border Israeli-Jordanian tourist complex south of the Dead Sea. At the same time, it is hoped, the Dead Sea will be refilled. After initially being pumped or sucked 170km above sea level, the water would then fall 500m into the Dead Sea, with mere gravity generating enough hydro-electric energy to power desalination plants creating up to 850 million cubic metres a year of fresh water, with big potential to ease dire regional water poverty, which leaves easily the worst-off of the partners, the Palestinians, with a mere 70 cubic metres of water per head (compared to 340 for Israel and 1,500 for the UK).

The project is colloquially known as “Red-to-Dead ” and the World Bank is conducting a $20m (£11m) feasibility study on behalf of all the Dead Sea’s “riparian partners”, Israel, Jordan and the Palestinian Authority. Its elegance lies in the way it would use the fact that the Dead Sea is so far below sea level. Of the possible solutions being canvassed, the most dramatic is the long-standing idea of a “peace conduit”, or 174km of canal tunnel and pipeline, which would bring sea water from the Gulf of Aqaba to the Dead Sea. Now it is a kilometre away, so those who do not want to walk take a wagon train hauled by a red tractor. Covered in black therapeutic mud from head to foot, Omar Taha, 47, an Israeli Arab from a village near Netanya, who has been coming here regularly since the spa opened, points to the repeatedly extended road from the hotel and says: “Of course it bothers me This is worse every year This used to be all water We need to find a solution.” Mr Taha is hardly alone. When the spa was constructed in 1986, its clients could walk a few feet to the shore for a bathe. You emerge strangely invigorated by the almost oily sensation afforded by the rich mineral composition of the water, and caked with salt.

With buoyancy so great it is almost impossible, once floating, to lower your legs, you can feel the sting of scratches you never knew you had. To lie in the waters of the Dead Sea, which famously has a salt concentration 10 times as high as that of the Mediterranean, is an unforgettable experience. “But it is a kind of paradigm for what is happening to the sea as a whole.” Nearby is the Ein Gedi Spa, famous for its mud wraps and rich, natural hot-water mineral baths and for its access to the sea. Instead it is “outrageously” – a word Mr Bromberg uses a lot – diverted to the bottling plant below us for the prized mineral water you can buy throughout Israel, or to supply the adjacent kibbutz and irrigate the botanical gardens it tends in the arid desert land. “Ein Gedi isn’t the reason for the problems of the Dead Sea,” Mr Bromberg says.