Sorek Desalination Plant
For Relieving Devastating Drought with a Sustainable Solution (Most Influential Projects: #39)
Few places in the world face a more dire water situation than Israel, where the vital liquid has been in short supply for millennia. In 1998, a new crisis loomed. Israel, like much of the eastern Mediterranean region, had its worst drought in 900 years.
To overcome such water insecurity, the Israeli government's Water Desalination Administration (WDA) launched a massive program at the turn of the century to build desalination plants across the country. But simply greenlighting construction wasn't enough. Plants also had to be cost-effective and environmentally friendly—or risk exacerbating the climate change that had magnified the region's water shortage in the first place.
PHOTO COURTESY IDE TECHNOLOGIES
The Sorek desalination plant stands as the program's crown jewel, building on decades of research and innovation. Funded, built and operated by a WDA-chosen consortium led by IDE Technologies, it is the largest-ever facility for reverse osmosis (a process that separates seawater from drinking water through pressure and membrane filtration). No chemicals are used in the filtration process, and it has cut costs by nearly a third since the 1990s.
“The Sorek desalination plant serves as a pinnacle of water security in Israel,” says Michael P. Tramer, vice president, sales and marketing, IDE Technologies. “The plant sets several significant industry benchmarks in desalination technology, capacity and water cost.”
Built on the Mediterranean coast, roughly 15 kilometers (9.3 miles) south of Tel Aviv, Israel, Sorek began operations in 2013, two years after construction launched. The timing couldn't have been better. In the past 30 years alone, Israel's natural water supply has declined 20 percent. By 2018, the country's lakes, riverbeds and aquifers were at 100-year lows. The Sorek plant now can supply drinking water to roughly one-fifth of Israel's population. The overall program was a sweeping success, too: By 2018, the majority of Israel's drinking water came from desalinated plants.
Innovation on Tap
The plant draws water from the Mediterranean Sea roughly 2.4 kilometers (1.5 miles) off the coast. To avoid endangering marine life—as well as minimize noise pollution—the suction for the intake pipes is very slow, operating at 0.15 meters (5.9 inches) per second. Gravity takes the water through underground pipes to a series of filters and purifiers. The team used a pipe-jacking method to install the pipelines, which allowed minimal impact on the environment and seabed, lower emissions and a longer lifetime on the pipeline.
The plant has two identical facilities to execute pretreatment. One of IDE Technologies’ major breakthroughs came in non-chemical water treatment. Gravity filters that contain gravel, quartz sand and anthracite strip away unwanted particles. The filtrated seawater is pumped to the reverse osmosis section through low-pressure booster pumps.
HOLD THE SALT
With membrane desalination, seawater passes through the tubes under pressure, forcing fresh water through the membranes while saltier water is held back. Most reverse osmosis plants have horizontal membranes, with an average clearing of 8 inches (20.3 centimeters). Sorek was the first large plant to use pressure tubes that are 16 inches (40.6 centimeters) in diameter, and they're also arranged vertically, requiring fewer materials to support the framework. Both decisions helped lower the project's final cost and reduce the plant's footprint.