Israeli water desalination insights

Print

By Eamonn Ryan

Waterwise, there are similarities between South Africa and Israel: both are dry countries with a long coastline. Like South Africa, the Israeli government owns all the water and has a duty to supply water to all residents. 

South Africa has much to learn from Israel. They have five desalination plants; we have one. The thrust of a Collective Wisdom lecture hosted by MDA Attorneys, was that among the mix of water solutions for the country, we should have more desalination plants.

CleanTechnicaA water desalination plant on the sea near the northern Israeli town of Hadera, where water pumped in from the Mediterranean Sea is pushed through rows of multilayered plastic membranes, emerging 90 minutes later as clean drinking water.
Image credit: Quique Kierszenbaum/MCT

Agreeing with this viewpoint, the Israeli Water Authority’s head of reclaimed water, Danny Greenwald, discussed by Skype from Israel his country’s experience with addressing challenges such as securing water resources for its rapidly increasing population and the finite nature of natural water supplies. The solutions Israel designed to address these issues are: an emphasis on the decrease in the overall water usage; use of cleansed wastewater in agriculture; and the implementation of new methods such as the desalination of seawater, which now provides almost unlimited water resources.

Greenwald points out that four of the country’s five desalination facilities were built by the private sector through a price auction. “The state is obliged to buy a quantity of water, whether it is used or not. Water is available and distributed to the Israeli population within a framework of quotas and cost structures,” he says.

Today, more than 87% of the wastewater in Israel is reused, and most of the water used for agricultural irrigation is reclaimed wastewater.

For many years, Israel made little progress in developing a national water strategy: the challenge faced by the country is similar to that of South Africa (and no doubt many others) in that the rain falls only in certain areas. In Israel, the dry season is from April to October. Its north has plenty rainfall, but the central region is drier and the south a desert. It also has a rapidly increasing population. Compounding this challenge, its government departments functioned in silos and competed with each other for budget. Only when an interdepartmental task team was finally established in 2007 was the process unjammed.

Israel’s changing demographics affect water consumption: agriculture consumes 49% of water (down from 85% in the past, a factor of the growing population); domestic uses 35%; industry 6%; neighbours get 7%, including the Palestinian Authority; and nature consumes 3%. The country’s average daily consumption of 170ℓ means it has an annual shortage of approximately 45% compared to natural sources.

Israeli water comes from four main water sources: groundwater that is extracted from aquifers through wells; surface water that is extracted from rivers and the Sea of Galilee; desalinated seawater; and reclaimed wastewater. One solution has been to transfer water from the rain-rich north to dry areas in the densely populated central region.

israel1Without water, just across the border, this is what Israel would look like.
Image credit: CleanTechnica  

Water efficiency is core to Israel’s self-sufficiency, and Greenwald explains that effective water use was achieved by ensuring water use is both measured and paid for. “That promoted water self-sufficiency for a few years, but as the population increased, it was no longer adequate. We realised we could not continue to use just our natural water sources as we had in the past to serve a growing population. We needed more water and decided to use manufactured water from two main sources: reclaimed wastewater and desalinated water. We started with reclaimed wastewater because 30 years ago, desalinated water was extremely expensive and we couldn’t afford it.

“Almost all the reclaimed water is used for agriculture, with a little for industry and suburban gardens. Today, 20% of the water used in Israel is reclaimed wastewater. This helped Israel for a few years but didn’t fully solve the problem, as the population keeps growing and you can only use reclaimed wastewater to the extent that you have wastewater to cleanse. So, we looked at desalination and today, there are five plants in Israel, all very large facilities of between 90 million m3/year to the largest 130 million m3/year, and all based on the Mediterranean. We are fortunate in Israel that most of our population lives along this coastline, making it more economical than pumping water 200–300km from the Sea of Galilee. As long as the population keeps growing, we will continue to build more and more factories for seawater desalination,” says Greenwald. The advantage of this strategy, he says, is that as there is more and more desalinated water in circulation, there will also be more wastewater to reclaim. The existing plants were built at more-or-less two-yearly intervals: 2005, 2007, 2009, and so on.

Greenwald says that what has fundamentally changed in Israel is its sources of water: 15 years ago, 77% of its water supply was from natural sources and today, the per cent of natural potable water has fallen to 35%.

“The other big change that has occurred during the 15 years, is the management of the system. Before 2007, that management was split among various government departments. Though everybody knew we needed a big water infrastructure, each year when it came to planning the next year’s budget, there was some other more urgent priority, another public hospital, or some new war in the Middle East — and never enough for the water sector. There was also the factor that desalination plant is expensive. In 2007, the interdepartmental (with civic representation) Israel Water Authority was founded on PPP principles, with the result that water prices jumped.

“This was unpopular, but it was nonetheless affordable for households and meant that we could effectively address the water shortage.” Greenwald points out that the cost of desalinated water is largely dependent on the cost of energy and Israel was fortunate in that just when it commenced its desalination drive, natural gas was found in the country, and its cost of energy is relatively cheap. He did not expect the cost of water to decrease, but nor would it rise much more.

He notes that this had at times caused a political problem in Israel: the various plants were built by the private sector based on government commitment to buying the production, like South Africa’s renewable energy programme. This fixed cost meant that the price could not come down. The downside is that even if something like climate change were to bring about increased rainfall, the infrastructure would still have to be paid for, so consumers should not expect the price to fall.

In conclusion, these processes have led to the fact that today, more than 87% of the wastewater in Israel is reused, and most of the water used for agricultural irrigation is reclaimed wastewater.