Israel a model for California in desalination

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A sign welcoming you to the Sorek desalination plant in Israel. (The original image is no longer available, please contact KCRW if you need access to the original image.)

California Governor Jerry Brown today approved a plan to spend $1 billion on addressing the state’s historic drought. That includes funding for flood protection, water-recycling projects and programs expanding drinking water supplies in small and poor cities.

Another option for increasing the state’s water supply is desalination – the process of turning salt water into drinking water – and it’s making a comeback. Santa Barbara officials plan to raise water rates this summer to pay for bringing the city’s desalination plant back online after decades of collecting dust.

To understand what all this means for California, let’s look at Israel, which gets about a third of its drinking water from the sea.

These pipes filter sea water, separating the clean water from the extra-salty brine, which is then sent back into the ocean.

The Sorek desalination plant is located on the Mediterranean coast, roughly 10 miles south of Tel Aviv, Israel. It’s the largest desalination plant in the world. The plant alone pumps out about 10 percent of the country’s drinking water and accounts for about 20 percent of its total water consumption.

Micha Taub, a chemical engineer and the plant’s chief technologist, points down into a large concrete silo. Inside, water is pouring out of a big pipe.

“This is the extra salty water that’s returned to the sea. Because we produce from each 100 percent of seawater, 50 percent fresh water, 50 percent is returned to the sea,” Taub said.

This plant could very well be California’s future. Of course, California is eight times the size of Israel, with five times as many people. Our ongoing drought is changing how we perceive water, making us a lot more like Israelis.

The Sorek plant's CTO, Micha Taub, in front of a model of an intake pipe that filters sea water through ultra-thin membranes. Photos by Avishay Artsy.
The Sorek plant’s CTO, Micha Taub, in front of a model of an intake pipe that filters sea water through ultra-thin membranes. (The original image is no longer available, please contact KCRW if you need access to the original image.)

“As an Israeli child, you’re raised with a culture of saving water,” said Udi Tirosh, director of business development at IDE Technologies, the company that built Sorek and is also building the Carlsbad desalination plant north of San Diego.

Israel has become a technological leader in desalination, out of necessity. The country is 60 percent desert. From its founding, the nation’s leaders knew the economy couldn’t operate without a steady source of water.

“New country, new state, scarcity of electricity, scarcity of water, scarcity of everything, but water was a critical thing,” Tirosh said. “You want life, you need water.”

IDE says the Carlsbad plant will be the largest seawater desalination plant in the Western Hemisphere. When it’s finished later this year, it’ll be able to pump out 50 million gallons of drinking water a day.

The salty discharge of the desalination process, before it's pumped back out to sea.
The salty discharge of the desalination process, before it’s pumped back out to sea. Photos by Avishay Artsy. (The original image is no longer available, please contact KCRW if you need access to the original image.)

This plant in Israel produces twice that amount. The water is filtered using a process called reverse osmosis. The seawater is pre-treated to get rid of seaweed and other stuff. It’s then pushed through a series of ultra-thin membranes that filter out salt and other impurities. Half of the seawater becomes drinking water, and the leftover half, which is extra salty, is dumped back into the Mediterranean.

Environmentalists have raised concerns that that brine kills sea life. Tirosh says that after the water is discharged, it quickly blends with the ocean water.

“So we get a very little effect on the sea,” he said. “The fishermen are not complaining, currently, so we’re happy.”

Israel’s neighbors, including Jordan and the Palestinians in the Gaza Strip, are also planning to build desal plants. “We’ll be happy to supply the technology and the facility to do that,” Tirosh said.

Desalination isn’t the only way Israel deals with water scarcity. Three-quarters of its sewage is recycled, and more than half of the water used to irrigate crops comes from treated sewage. The country uses a high-tech grid to closely monitor pipes for potential leakage.

Just some of the things California is looking to do to catch up.

Find out how one desalination plant in Santa Barbara might come back online.