HEALTH AND SANITATION
33
Desalination only part of
the water scarcity solution
The technology is improving and expanding, but only
truly effective when paired with conservation.
By Anne V. Sonner
“WATER, WATER EVERYWHERE,
NOR ANY DROP TO DRINK.”
Samuel Taylor Coleridge, who wrote those words about
water in The Rime of the Ancient Mariner — a poem
describing a sea voyage in 1798 — had probably never
heard of desalination. No doubt over the centuries many
sailors died of thirst in the middle of oceans full of vast
amounts of water. Of course, seawater — about 97 per
cent of the Earth’s water — is unfit for drinking or for
irrigating crops, unless processed to remove the salt.
Official reported in 2008 on the technology and progress
of desalination. This article follows this important water
issue, especially in light of increasing water needs in
many areas of the world.
WHERE IN THE WORLD IS DESALINATION?
The short answer: in several countries. Some use it a lot;
others not so much.
According to the most recent statistics from the
International Desalination Association, there are
18 426 desalination plants worldwide, in 150 countries.
That translates into 22.9 billion gallons per day, with
more than 300-million people relying on desalinated
water for some or all of their water needs. (The world’s
current population is about 7.5 billion.) Another source
says 21 000 desalination plants worldwide produce
more than 3.5 billion gallons of potable water each day.
Most water for drinking and farming is obtained from
traditional sources: rivers, lakes, and groundwater, with
water reclamation and recycling. However, these sources
are not always adequate, especially during droughts.
The United Nations website states that approximately
one per cent of the world’s population is dependent on
desalinated water to meet daily needs.
A few countries rely extensively on desalination; for
others it supplements primary water supplies. Poseidon
Water in San Diego states that desalination is most
www.plumbingafrica.co.za
used in countries in the Middle East, the Mediterranean,
and the Caribbean, where traditional water supplies are
limited due to arid climates or island locations. Saudi
Arabia is the world leader, desalinat ing water to produce
70 per cent of its drinking water.
Israel is also extremely impressive. This arid country
has amazingly progressed from water shortage to
surplus. A 2017 article in NoCamels describes how that
happened. Tomer Efrat, process engineering manager
at Israel Desalination Enterprises Technologies, said,
“We used to have enough water from the Sea of Galilee
and underground aquifers. But in the 1990s, we felt
the water scarcity more and more.” Desalination, which
provides 60 per cent of Israel’s domestic water, plus
drip irrigation, water recycling, and sustainable water
conservation policies, have increased Israel’s water
supply and shrunk its desert land. “Today, no one in Israel
experiences water scarcity,” Efrat said.
India, the world’s second-largest country with 1.3-billion
people and a serious shortage of potable water, is looking
to Israel for help with desalination, the Hindustan Times
reported in May 2017. Leaders of Israel and India plan to
meet to discuss Israel’s high-end technologies. India is
considering building three new desalination projects on
the western coast and southern tip of the country.
Russ Chaney
In the spirit of the sharing
of unique experiences
that shape the plumbing
industries in our respective
nations, the following article
looks at desalination and
its potential benefits and
drawbacks. Written by
IAPMO correspondent
Anne V. Sonner, it is the
next in a regular series of
similar articles that will run in
this magazine.
Also in the news, the ambitious Red Sea–Dead Sea Canal
is a joint venture between Israel and Jordan to build a
desalination plant on the Red Sea where they share a border.
The water would be divided among Israelis, Jordanians, and
Palestinians, and the brine piped to replenish the Dead Sea.
“By 2020, these old foes will be drinking from the same
tap,” Scientific American reported hopefully.
Australia, the driest inhabited continent on Earth, became
drier during a long drought from 1997 to 2009. As a
result, it built more desalination plants, with 30 now
operating. Many of the plants are powered by renewable
wind or wave farms, and some by solar.
Continued on page 35 >>
July 2018 Volume 24 I Number 5