Extracting the Mediterranean Sea’s water could provide
Israel with an unquenchable supply of clean water
By Ben Sales
As construction workers pass through sandy
corridors between huge rectangular buildings at this desalination plant on
Israel’s southern coastline, the sound of rushing water resonates from behind a
concrete wall.
Drawn
from deep in the Mediterranean Sea, the water has flowed through pipelines
reaching almost 4,000 feet off of Israel’s coast and, once in Israeli soil,
buried almost 50 feet underground. Now, it rushes down a tube sending it
through a series of filters and purifiers. After 90 minutes, it will be ready
to run through the faucets of Tel Aviv.
Set to
begin operating as soon as next month, Israel Desalination Enterprises’ Sorek
Desalination Plant will provide up to 26,000 cubic meters – or nearly 7 million
gallons – of potable water to Israelis every hour. When it’s at full capacity,
it will be the largest desalination plant of its kind in the world.
“If we
didn’t do this, we would be sitting at home complaining that we didn’t have
water,” said Raphael Semiat, a member of the Israel Desalination Society and
professor at Israel’s Technion-Israel Institute of Technology. “We won’t be
dependent on what the rain brings us. This will give a chance for the aquifers
to fill up.”
The new
plant and several others along Israel’s coast are part of the country’s latest
tactic in its decades-long quest to provide for the nation’s water needs.
Advocates say desalination — the removal of salt from seawater – could be a
game-changing solution to the challenges of Israel’s famously fickle rainfall.
Instead of the sky, Israel’s thirst may be quenched by the Mediterranean’s
nearly infinite, albeit salty, water supply.
Until
the winter of 2011-12, water shortages were a dire problem for Israel; the
country had experienced seven straight years of drought beginning in 2004.
The Sea of Galilee (also known as Lake Kinneret), a major freshwater source and
barometer of sorts for Israel’s water supply, fell to dangerous lows. The
situation got so severe that the government ran a series of commercials
featuring celebrities, their faces cracking from dryness, begging Israelis not
to waste any water.
Even as
the Sea of Galilee has returned almost to full volume this year, Israeli
planners are looking to desalination as a possible permanent solution to the
problem of drought. Some even anticipate an event that was once unthinkable: a water surplus in Israel.
Israel
Desalination Enterprises opened the first desalination plant in the country in
the southern coastal city of Ashkelon in 2005, following success with a
similar plant in nearby Cyprus. With Sorek, the company will own three of
Israel’s four plants, and 400 plants in 40 countries worldwide. The company’s
U.S. subsidiary is designing a new desalination plant in San Diego, the $922
million Carlsbad Desalination Project, which will be the largest desalination
plant in America.
In
Israel, desalination provides 300 million cubic meters of water per year –
about 40 percent of the country’s total water needs. That number will jump to
450 million when Sorek opens, and will hit nearly 600 million as plants expand
in 2014, providing up to 80 percent of Israel’s potable water.
Like
Israel’s other plants, Sorek will work through a process called Seawater
Reverse Osmosis that removes salt and waste from the Mediterranean’s water. A
prefiltration cleansing process clears waste out of the flow before the water
enters a series of smaller filters to remove virtually all the salt. After
moving through another set of filters that remove boron, the water passes
through a limestone filter that adds in minerals. Then, it enters Israel’s
water pipes.
Semiat
says desalination is a virtually harmless process that can help address the
water needs prompted by the world’s growing population and rising standard of
living.
“You
take water from the deep sea, from a place that doesn’t bother anyone,” he said.
But
sesalination is not without its critics. Some environmentalists question
whether the process is worth its monetary and environmental costs. One cubic
meter of desalinated water takes just under 4 kWh to produce – that’s the
equivalent of burning 40 100-watt light bulbs for one hour to produce the
equivalent of five bathtubs full of water. Freshwater doesn’t have that cost.
Giora
Shaham, a former long-term planner at Israel’s Water Authority and a critic of
Israel’s current desalination policy, said that factories like Sorek could be a
waste because if there is adequate rainfall the desalination plants will
produce more water than Israel needs at a cost that is too high. Then, surplus
water may be wasted, or international bodies like the United Nations could
pressure Israel to distribute it for free to unfriendly neighboring countries,
Shaham said.
“There
was a long period of drought where there wasn’t a lot of rain, so everyone was
in panic,” Shaham said. “Instead of cutting back until there is rain, they made
decisions to produce too much.”
Fredi
Lokiec, an executive vice president at the Sorek plant, says the risks are
greater without major desalination efforts. Israel is perennially short on
rainfall, and depending on freshwater could further deplete Israel’s rivers.
“We’ll
always be in the shadow of the drought,” Lokiec said, but drawing from the
Mediterranean is like taking “a drop from the ocean.”
Some
see a water surplus as an opportunity. Orit Skutelsky, water division manager
at the Society for the Protection of Nature in Israel, says desalinated water
could free up freshwater to refill Israel’s northern streams and raise the
level of the Sea of Galilee.
“There’s
no way we couldn’t have done this,” she said of desalination. “It was the right
move. Now we need to let water flow again to the streams.”
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