https://news.yahoo.com/water-scarce-gulf-states-bank-desalination-cost-013607649.html
[images in online article]
Water-scarce Gulf states bank on desalination, at a cost
Sur (Oman) (Oman) (AFP) - "We have water, and it's the most important
thing in a house," says Abdullah al-Harthi from the port city of Sur in
Oman, a country that relies on desalination plants.
But for Oman and the other Gulf countries dominated by vast and
scorching deserts, obtaining fresh water from the sea comes at a high
financial and environmental cost.
In Sur, south of the capital Muscat, water for residents and businesses
comes from a large desalination plant that serves some 600,000 people.
"Before, life was very difficult. We had wells, and water was delivered
by trucks," the 58-year-old told AFP. "Since the 1990s, water has come
through pipes and we've had no cuts."
But these benefits -- relying on energy intensive processes that produce
carbon emissions -- do not come without a cost, particularly as global
temperatures rise.
The United Nations says 2019 is on course to be one of the hottest three
years on record.
And there is another impact: the desalination plants produce highly
concentrated salt water, or brine, that is often dumped back into the ocean.
Researchers say more than 16,000 desalination plants around the globe
produce more toxic sludge than freshwater.
For every litre of freshwater extracted from the sea or brackish water,
a litre-and-a-half of salty slurry is deposed at sea or on land,
according to a 2019 study in the journal Science.
All that extra salt raises the temperature of coastal waters and
decreases the level of oxygen, which can conspire to create biological
"dead zones".
The super-salty substance is made even more toxic by the chemicals used
in the desalination process.
Oman's bigger neighbours produce the bulk of the brine.
More than half comes from just four countries -- Saudi Arabia, at 22
percent, United Arab Emirates with 20 percent, and smaller shares by
Kuwait and Qatar, according to UN data.
"Brine production in Saudi Arabia, UAE, Kuwait and Qatar accounts for 55
percent of the total global share," according to the United Nations
University Institute for Water, Environment and Health.
It said new strategies are needed "to limit the negative environmental
impacts and reduce the economic cost of disposal".
This would help "to safeguard water supplies for current and future
generations".
- Savings, recycling -
At the Sur plant, "almost no chemicals" are used during the
pre-treatment phase, as the water is naturally filtered through the
cracks of karst rocks, said Mahendran Senapathy, operations manager at
French company Veolia which runs the plant along with an Omani firm.
There are other ways to safeguard freshwater supplies, from encouraging
savings and efficiently to recycling wastewater.
Antoine Frerot, chief executive of Veolia, said wastewater recycling
will help resolve the problem of water scarcity.
He also pointed out that "reused water is less costly," nearly one third
less than that won through desalination.
Omani authorities continue to mount campaigns urging people to use water
wisely, mindful that other demands -- especially the energy sector --
also guzzle up large amounts.
Across the Gulf, huge amounts of water are used not just for homes,
gardens and golf courses, but also for the energy sector that is the
source of the region's often spectacular wealth.
- Thirsty fracking -
On the edge of the Arabian peninsula's "Empty Quarter", the world's
largest expanse of sand, lies the Khazzan gas field, operated by BP and
the Oman Oil Company.
The method used to extract the gas here is hydraulic fracturing -- more
commonly known as fracking -- said Stewart Robertson, operations manager
at the site.
The method requires huge amounts of water. The site is supplied by a
facility that provides 6,000 cubic metres of water a day, extracted from
an underground aquifer 50 kilometres (30 miles) away.
Fracking involves directional drilling and then pumping water, sand and
chemicals at high pressure to fracture rock and release the hydrocarbons.
The rock formations that hold the gas are "like a big sponge with lots
of little holes in it," said Robertson, explaining that fracking is the
process "to open those holes slightly to take the gas out".
So the more the region extracts oil and natural or shale gas, "the more
they need water," said Charles Iceland of the World Resources Institute.
"The Middle East is projected to need more and more energy," he said.
"So that means the situation is going to get worse."
"On the other hand," he said, "if they can produce power using solar
photovoltaic technologies, which are getting reasonably priced in the
Middle East, that would take care of a lot of the problem because solar
PV doesn't need much water.
"You need just some water to clean the solar panels."
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