Water, hold the salt

In 1961, President John F. Kennedy presided over the opening of a new industrial facility promising to use the latest scientific achievements to benefit mankind. This, he said at the opening ceremony, was “a work that in many ways is more important than any other scientific enterprise in which this country is now engaged.”

You’d be forgiven for thinking this marked a milestone in the space race. But no — the speech celebrated the opening of a new desalination plant in the Gulf Coast city of Freeport, Texas. The Southwest had been suffering from a punishing drought that led to wide-scale water rationing, and Kennedy’s appearance at the inauguration of the Saline Water Conversion Plant was an early capstone for the US Office of Saline Water. The office, established in 1955, poured millions into the cause of harnessing saltwater for residential, agricultural, and commercial use. 

More than 60 years later, desalination has become a multibillion-dollar global enterprise. Just 3% of the world’s water supply is fresh, with the vast majority of that trapped in ice caps and glaciers or found underground. The remaining accessible freshwater sources strain under the weight of growing demand, leaving government and utilities a handful of choices: better conservation, reuse, or desalination. Population growth — including in arid and drought-prone regions like the Gulf states and northern Africa — shows no signs of slowing down, driving massive investment in plants that can convert seawater. Over 20,000 plants already operate globally, and industrial facilities that rely on ultrapure water, like semiconductor manufacturing, will add to the demand. Even electrification drives the desalination industry: an immense amount of freshwater is needed for mining lithium and other metals key to battery technologies. 

“It’s not growing because somehow there is more profit in desalination as a business,” said Yoram Cohen, a professor and director of the Water Technology Research Center at UCLA. “It’s growing because there is a need for it.”

And the growth is incredible. The global market for desalination, roughly $20 billion, is expected to more than double by 2032, Straits Research found. Global Water Intelligence, a market-research firm, forecast that the number of large desalination plants will increase from 1,700 to nearly 2,000 by 2028. Israel’s soon-to-open Sorek B desalination plant, for instance, cost $1.5 billion and will span 1 million square feet, enough room to fit 46 Boeing 737 jets.

Data from the International Desalination and Reuse Association shows that the amount of water desalinated daily has skyrocketed over the last two decades, from 27 million cubic meters in 2003 to 99 million cubic meters in 2023. For context, that’s about 40,000 Olympic-sized swimming pools. Projects planned for Morocco, Spain, Algeria, Egypt, Chile, England, and Israel have led GWI to label this moment the “largest capacity boom in the industry’s history.” More than $40 billion is being spent in the Middle East alone. Massive engineering, infrastructure, and construction firms around the world, like Veolia, Metito, Acciona, and Wetico, have dominated the international market. Many American engineering firms have found business opportunities in the sector overseas, offering consulting, design, and architectural services. Jennifer Osgood, an environmental engineer and senior vice president at infrastructure consulting firm CDM Smith, said her company has seen more gigs overseas and is currently working on the technical, legal, and design aspects of a large project in Jordan.

Desalination technology has gotten more efficient over time, but it’s still an expensive and energy-consuming way to get freshwater. Historically, desalination involved energy-intensive thermal processes that boiled seawater to separate the steam from solids. The procedure has been around for centuries; as secretary of state, Thomas Jefferson ordered that the government print guides to desalination on the back of permits for 18th-century sailing ships. In 1959, UCLA researchers Sidney Loeb and Srinivasa Sourirajan created the process used in most plants today: reverse osmosis, which forces highly pressurized seawater through a series of pumps and membranes to filter out freshwater. Loeb, who patented a membrane he developed for $14,000, spawned a multibillion-dollar industry.

The average projected cost of creating a cubic meter of freshwater has gone from roughly $1.10 in 2000 to nearly $0.50 today, GWI data shows. Jay Lund, a professor of environmental engineering at the University of California, Davis, estimated that the cost has dropped about 90% in the last 50 years. But energy remains a key variable cost of desalination. It’s the most energy-intensive means of delivering drinking water, making up anywhere from a third to over half of the total cost of separating out salt and minerals. In Cyprus, where desalination supplies most of the freshwater, the process generates 2% of the country’s total greenhouse-gas emissions and uses 5% of the island’s power.

In the US, desalination has not been widely adopted. One of the ironies of the industry is that as rainfall levels decline and drought conditions worsen — often leading to calls for desalination — the running water that would provide cheap and reliable hydropower is curtailed. The droughts that have hit the western US over the last two decades cost billions of dollars, in part because of increased energy prices. 

“People like the allure of seawater desalination because it seems like you’re creating this new supply, and it’s a technology-based approach, so it seems less vulnerable,” Heather Cooley, director of research at the Pacific Institute, said. 

At one point, during the drought-stricken early 2010s, California was set to build 17 desalination plants up the Pacific coast. But those plans have fallen to the wayside. The state’s approach tends to vacillate between efforts to conserve water and efforts to invest in costly new plants, Cooley said, which have proven unsustainable. Other plants have found themselves handicapped by local bureaucracy. The Santa Clara Valley Water Authority near Silicon Valley is spending more than $1 million just to study the idea of adding a desalination plant.

But the thirst for desalination is unlikely to be quenched anytime soon. Cohen said he’s currently working on a small-scale demo project in the Salinas Valley, an agricultural center that’s seen its freshwater drained by extensive farming and fertilizer use. The plant would use technology to operate autonomously and clean the brackish water for local use. Osgood said more and more US utilities are running feasibility studies for domestic desalination, as rising sea levels and other issues have caused many to start looking at diversifying their water supply.

Cohen sees the combination of increased population, agricultural demand, and the climate crisis as an unavoidable megatrend that means more areas across the world will face the same water shortages as the Salinas Valley. He estimated 2 million people in California alone have contaminated drinking water.

“We have a very large number of communities that rely on potable water, and their potable water sources are contaminated,” Cohen said. “You don’t have to go to a third-world country, you know, to find people that don’t have drinking water.”

In the Middle East, the megaprojects will only multiply. Earlier this year, taps in Abu Dhabi began flowing with the freshwater produced at the Chinese-built Taweelah Independent Water Plant, which cost $900 million to construct, and will be partially powered by a 300-acre-plus solar field. The operator, Emirates Water and Electricity Company, has four more large-scale plants in the works. 

Patrick Sisson is a reporter covering cities, businesses, and technology.