For a city in the Arabian desert, Dubai is surprisingly well-watered. Grassy lawns and man-made duck ponds dot neighborhoods called The Springs and The Lakes. Across the United Arab Emirates, crowds flock to golf courses, water parks and synchronized fountains.
Yet a water crisis is looming for the U.A.E. and its neighbors in the Persian Gulf region, one of the most water-stressed in the world. So far, Gulf Arabs have relied on fossil fuel-burning desalination plants to produce most of the water their swelling populations and expanding industries consume. Now they’re adopting cleaner technologies and starting to harness their abundant sunshine to make drinkable water from the sea.
1. How does seawater become drinkable?
By the process known as desalination. Gulf Arab countries rely on desalinated seawater for most of their non-agricultural needs -- from bottled water to residential plumbing. Saudi Arabia is the world’s biggest producer of desalinated water, and the broader Middle East and North Africa region is home to 48 percent of the desalination capacity currently in operation. More than one-third of the water consumed annually in Abu Dhabi, the U.A.E.’s largest emirate, comes from desalination plants, enough to fill almost 450,000 Olympic-sized swimming pools.
2. How is it done?
For now, mostly by burning natural gas or oil to boil seawater, lots of it, then recovering droplets of distilled fresh water -- a process known as thermal desalination.
3. What’s the downside to desalination?
It’s expensive and can be dirty, even though the water comes out clean. Using fossil fuels means these plants contribute to greenhouse gases that exacerbate climate change. They also dump salt back into the ocean in a heated, concentrated brine. This discharge often contains heavy metals and chemical pollutants and is seen as a serious threat to marine ecosystems in the semi-enclosed Gulf. By one estimate, producing 1 cubic meter of desalinated water can cost from 70 cents to $1, while the same amount of treated groundwater costs 15 cents to 40 cents. One desalination plant producing about 7 million gallons (about 26,500 cubic meters) per day -- a supply sufficient for as many as 200,000 people -- can guzzle as much energy as an oil refinery or a small steel mill.
4. Is there a better way?
Gulf nations could accelerate the switch to cleaner technologies such as reverse osmosis, which passes seawater through membranes to remove salt and other impurities. Reverse osmosis consumes one-quarter or less of the energy of thermal facilities. It’s the most prevalent method in much of the world, including the U.S., the second-largest producer of desalinated water. But like thermal plants, reverse osmosis facilities in coastal areas discharge brine back into the sea.
5. Are there alternatives to desalination?
The Gulf countries could reduce their water demand by doing more to treat and recycle wastewater, but that by itself wouldn’t likely keep up with growing needs. Governments could also try to limit consumption by reducing water subsidies, though this might be politically difficult. Other steps are largely unproven. For instance, the U.A.E. has been seeding clouds with salt crystals fired from airplanes to produce more rain. Though cloud seeding is an idea that’s been around for 70 years, its effectiveness is still a matter of debate.
6. How does solar power fit in?
Abengoa SA, a Spanish energy and environment company, is developing the world’s largest solar-powered desalination plant in Saudi Arabia along with a local water firm. The $130 million facility at Al Khafji City on the Gulf coast would be the first large-scale desalination plant to be powered by solar energy, and it’s designed to use reverse osmosis. Until recently, the abundance of cheap or subsidized oil and gas made solar power a less economically viable choice. Now the plunging price of solar energy may spur an expansion of sun-powered desalination and could even cut the price of water.
7. How bad is the water shortage in the Gulf?
The Middle East-North Africa region has the world’s scarcest supplies of water, but Gulf Arab countries consume more of it per person than anywhere else, according to the World Bank. More than 60 percent of the people in MENA nations live under conditions of high or very high water stress. All six Gulf Cooperation Council countries -- Saudi Arabia, Kuwait, Bahrain, Qatar, Oman and the U.A.E. -- are likely to be “extremely highly stressed” by 2040, according to the non-profit Washington, D.C.-based World Resources Institute.
8. What’s causing that?
Gulf nations use their groundwater mostly for agriculture despite earning only a tiny economic return for depleting an essential resource in the parched Arabian Peninsula. Farming accounts for more than 60 percent of groundwater use in Abu Dhabi yet contributes less than 1 percent to the sheikhdom’s gross domestic product. At current consumption rates, the oil-rich emirate may run out of groundwater “within a few decades,” the Abu Dhabi Environment Agency said in a 2017 report.
9. How about other Gulf countries?
Kuwait uses 20 times more surface and groundwater than it can replace each year on a long-term basis -- the highest depletion rate in the GCC, according to a 2008 study by the Food and Agriculture Organization. The U.A.E. is close behind, while Saudi Arabia uses almost 10 times its replacement rate, the study shows. India, by contrast, consumes much less fresh water than it’s able to replenish each year -- 34 percent. The U.S. uses only 16 percent of its renewable water resources, and Brazil less than 1 percent, FAO data show.
The Reference Shelf
Ranking of the world’s most water-stressed countries in 2040 by the non-profit Washington, D.C.-based World Resources Institute.
The World Bank report “Beyond Scarcity: Water Security in the Middle East and North Africa,” published in 2017.
Food and Agriculture Organization of the United Nations’ AQUASTAT global water information center.
World Resources Institute’s AQUEDUCT Water Risk Atlas.
Abu Dhabi State of Environment Report 2017.
— With assistance by Jinan Warrayat, and Laurence Arnold
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