Israel is at the forefront of both ground-breaking technology and innovative environmental solutions. A stellar example of how Israel combines the two is the Shafdan wastewater treatment plant, located in Rishon LeZion, five miles south of Tel Aviv. Shafdan represents another success story that, together with drip irrigation and advanced desalination plants, has positioned Israel as perhaps the most resourceful nation in the world when it comes to addressing the critical issue of scarce water resources.
Among the largest facilities of its kind, Shafdan treats and purifies sewage from the Dan Region, encompassing Tel Aviv and the central districts located along the Mediterranean coast. All told, the region is home to 3.5 million Israelis, making it the country’s largest metropolitan area.
The plant is part of Igudan, an acronym for the Dan Regional Association of Towns for Environmental Infrastructure. The fact that Igudan was founded in 1955 underscores Israel’s longstanding, proactive approach to sustainability.
Israel is dependent on three water sources, each of which has become problematic in its own way: the Kinneret, which is steadily receding; the shore aquifer, with its ever-greater increases in salinity; and the mountain aquifer, which is becoming contaminated due to proximity to industrial zones. Additionally, Israel has had to contend with continuous years of drought, with a concurrent increase in population and water consumption.
Consequently, the idea of treating wastewater became another inventive Israeli means of problem-solving. Shafdan spokesman Meir Ben-Noon points out that because sewage is 99.8 percent water, “the potential to reuse it is huge. The objective of the Shafdan plant is to exploit that potential, ” otherwise, he says, “sewage just goes on contaminating the rivers, lakes and the sea.”
Speaking to a representative from Development Corporation for Israel/Israel Bonds, the company that has helped build every sector of Israel’s economy, Ben-Noon proudly notes that “Israel is the world leader in water recycling, and Shafdan is the main reason.”
Even the UN, a body not known for its admiration of Israel, praised Shafdan in a 2012 report on creative ways of tackling environmental issues.
Although the facility is huge, encompassing over 125 acres, it is operated by less than 50 employees, because the purification process is the result of an ingenious combination of microorganisms and advanced technology.
“Every day, ” says Ben-Noon, “we receive 98 million U.S. fluid gallons of wastewater from 23 cities” via a conveyance system located 100 feet below ground. The conduit is 6.5 feet in diameter and stretches 75 miles. Once the sewage reaches Shafdan, the multi-stage purification process begins with pretreatment. Bar screens, vertical steel bars spaced between 1 to 3 inches apart, remove large objects – bags, diapers and cell phones are examples cited by Ben-Noon – that are subsequently disposed of in landfills.
Following the initial filtering process, basins separate the remaining grit, oils and fat. Grit sinks to the bottom and is pumped into four sand separators. Oil and fats float to the surface and are transported to an adjacent plant that recycles them for industrial use.
Next comes biological purification, whereby microorganisms digest organic materials in the sewage. Special ventilators generate oxygen-saturated areas to accelerate the digestion process. Whatever settles to the bottom is sludge, and what remains on top is treated wastewater that is transferred to large sand fields used to filter the water to potable levels. “Sand, ” explains Bar-Noon, “is considered to be the most natural and best filter.”
The fields, managed by Mekorot, Israel’s national water company, are the final treatment phase. They are flooded with wastewater that eventually sinks through nearly 100 feet of sand, a filtration process that takes 400 days. At the end of the complex procedure, the water is pumped out, and what was once raw sewage has achieved a quality that, says Bar-Noon, “is very similar to drinking water.”
The ultimate result is truly impressive. Over the course of a year, Shafdan treats 35.6 billion U.S. fluid gallons of wastewater that supplies fully 70 percent of the irrigation needs of the Negev and 10 percent of the water needs of the entire country. Not even the sludge goes to waste, as it is mixed with coal ash and lime to produce 70, 000 tons of fertilizer each year.
Small wonder, then, that Shafdan attracts government officials, environmentalists and students from around the world, eager to utilize Israeli technology in their respective countries. It works the other way as well, with Israeli experts traveling abroad to help construct wastewater treatment facilities in countries including the U.S., China and Australia.
“For Israel, “says Bar-Noon, “Shafdan is really something to be proud of. It is an international source of pride.”