Israel is a rare example in the world of a water-starved country that has overcome desert and semi-arid conditions and many periods of drought to create water resources that have allowed it to supply enough water to its own population (and substantial amounts to its Palestinian and Jordan neighbors). This, despite increasing its population by more than ten times since its creation in 1948.
How has it succeeded in doing this as the world stumbles into greater and greater water shortages?
Up to recently, the main suppliers of water in Israel were the Sea of Galilee—the Kinneret, and the large two aquifers—underwater collections of water—one running along near the Mediterranean coast in the west and one along the mountain ranges in the east. With the many droughts we have experienced recently and the increased evaporation of water due to a rise in temperature over the last few decades, the water level at these sites has fallen so much that today no water is pumped out of the Kinneret and only small amounts of water are taken from the depleted aquifers.
How have we managed to maintain our water supply?
1. Drip irrigation
This was created in Israel by an immigrant from Poland, Simcha Blass, and first used in 1965. Plastic pipes containing small holes which allow water to drip through them at controlled rates are placed near the plants either on the surface or under the ground in the area of the roots. The water also contains nutrients and pesticides. Compared to spraying with water or flooding the fields, this system reduces the volume of water and nutrients and pesticides needed by about 80% and yet increases the yield by 2-5 times. The roots are smaller than with other watering methods since the plant does not need to seek out water and nutrients; they are readily supplied. The empty areas adjacent to the plant are not watered by this method so that less weeds will grow there, reducing the work needed to care for the plants. In addition, the leaves are less likely to be infested with hostile pests since they remain dry and therefore attract less pests. There is no evaporation of water as there is in spraying or flooding. By avoiding surface pesticides and fertilizer such as manure, there is less contamination of nearby water sources, while flooding or spraying can cause the runoff of these agents into streams, rivers, or lakes. The fertilizer can cause algae to grow which uses up oxygen which in turn can kill the fish and other acquatic life. The fertilizer can also contain bacteria which contaminates the water and infects people and wildlife while the pesticides can be toxic and poisonous. All these serious problems are avoided by drip irrigation.
Drip irrigation allows plants to be grown and flourish in sand. In the Negev, this is a major blessing and has helped to fulfill Ben Gurion's dream of converting the Negev into an agricultural paradise.
The vast majority of agriculture in Israel uses drip irrigation and over 110 countries have now been taught by Israel how to use it. The growth of sales of this method, as well as related agricultural technology, to these nations is tremendous and has reached 2.5 billion dollars annually. This is expected to climb to 10 billion dollars in the next few years, as its' use increases world-wide. Drip irrigation is now used widely in China, India, Africa, South America and other areas to feed their growing hungry masses. Reports from the people of these countries suggest that they truly feel it is a miraculous blessing.
2. Reuse of sewage water
This was started in the 1960s in Israel. Almost all the sewage water from home and industry in Israel is now collected in pipes and sent to plants where it is treated and disinfected. The last stage of the disinfection is to filter the water through several hundred meters of ordinary sand over six to twelve months which helps to make the water even more pure; not pure enough for drinking but good enough to use in agriculture. It is then transferred to one of 250 reservoirs where it can then be used safely for agriculture. The great amount of water produced by this method demands even more reservoirs than we have at present and the Jewish National Fund is now planning to spend about half a billion dollars on building 90 more reservoirs over the next few years to keep up with demand. Over 90% of the sewage water in Israel is now used for agriculture and it supplies about 75% of the water needed for agriculture. California, which suffers from a major drought, also treats the sewage, but reuses only 5% if it for agriculture, the rest is thrown into the ocean. The closest country in terms of reuse is Spain but it only uses 18% of its sewage water.
3. Use of sea water-desalination
In the last ten years, five plants have been set up along the coast from Ashkelon to Hadera. Each plant costs about half a billion dollars to build. These plants suck the water from the sea and pass it through filters with very tiny openings (pores), tiny enough to remove all the salts and other factors. The pure water is then used for home and industrial purposes. Compared to previous methods of desalination involving removing the salts by freezing the water or distilling it, this method is inexpensive (our water bills are not high). It was developed by an American, Sidney Loeb, who made aliyah and improved it at Beer Sheva University. His filter method (called reverse osmosis) is now in use throughout the world and Israel is a major supplier of the technology. In some areas such as Cape Town, South Africa, which is undergoing a severe drought, its use is desperately needed to avoid an almost complete lack of water for its four million residents. Similarly, San Diego in Southern California, the serious drought demanded its use, and Israel helped in its construction there. And many more such plants along the California shore are being planned. Israel itself is now feeling the results of this last drought which has gone on for five years. One solution is to build another three desalination plants over the next five years to keep up with the demand. One of these three plants will send some water to the Kinneret to make sure the water level does not fall below the danger line where the water could become too salty and acidy.
4. Brackish water
All water pipes may leak, and in some places like New York and London up to half the water in these pipes is lost from leaks before it even gets to the city. To imagine what this means, one day's loss is the equivalent of 60 seconds of all water flowing over Niagara Falls. Israel has recently cut these leaks down from about 16% to about 3% by careful monitoring water use everywhere in the country, spotting the leaks within a short time (seeing a sudden spike in water use) and stopping the leaks within a few minutes to a few hours. Israel is also working on a system that can send a machine through the pipes to fix the leaks from inside the pipes.
5. Prevention of leaks
In the Negev, there is a huge amount of water that has been there for hundreds of thousands of years and can supply 10% of Israel's water needs, but it is very salty—but at least 10 times less salty than sea water. While some of it is desalinated and then used for agriculture. surprisingly this slightly brackish water may itself make some vegetables (tomatoes, beans, cucumbers, and lettuce) and some fruits tastier, sweeter, and with a more pleasant texture than normal water and may allow for a longer shelf life. Similarly, trees such as date and olive trees may produce more and also more tasty fruit than with regular water. The fact that these fruits and vegetables grow all year round especially in the winter in the Negev means that farmers can get a good price all year long in Europe. Several varieties of fish also grow well in such brackish water.
6. Use of special seeds in agriculture that require less water
For example, a new kind of wheat has a shorter stock and therefore needs less water. A new tomato has less leaves and more tomatoes, yet, requires less water.
Other things Israel does to preserve our excellent water status include:
1. Seeding the rain clouds with che. icals. This increases the amount of rain by 20% but rain only supplies 2% of all our water.
2. Demanding that our toilets have dual flush levels, one for liquid and one for solid waste.
3. Reducing the length of time in the shower.
4. Discouraging landscaping of parks or homes that consumes excessive amounts of water.
5. Discouraging the use of crops that require a great deal of water, such as cotton.
6. Providing financial incentives to researchers who are looking for new water saving technologies.
7. Educating the population at all ages about water conservation.
8. Since the 1920s, Israel has been blessed with excellent water experts who work with the government to build dams, reservoirs, pumping stations, pipelines, and water industries to supply the country with water, adapting the methods, as needed.
The implications of water shortage
About 60% of the world's land mass already has some shortage of water. As the population is predicted to grow from 7 to 9 billion over the next 20 years, these extra mouths will need food and water, both of which are becoming in shorter and shorter supply as the droughts persist. Need we go farther away than Syria which has experienced more and more water shortage over the last two decades due to drought.. Lack of government concern, poor care of aquifers, leaky pipes, overpumping the aquifers and so on, led to poor crops, lack of wheat and other grains for people and herds, death of the herds, polluted water with sickness etc. People moved into the cities but they were unemployed, poor, bitter, hungry and ill. When they turned to Assad to complain, he shot them. The rest is history. This scene is being played out throughout the Middle East and Africa, Russia, China India and has led to the slaughter of many people and the displacement of many more,
These shortages are not just in the third world. The aqiuifer in central USA, which stretches from the Dakotas in the north all the way down to Texas in the south, will be dry by 2025. It supplies a high percentage of the grain, beef, milk, fruits, and vegetables to America and much to the world. Food all over will become scarcer and more expensive and this just angers people more with Jordan as a recent example. Israel's water solutions are already bringing a bright light to these nations.
Donald Silverberg MS, MSc, FRCP, is a Professor of Medicine (emeritus) Tel Aviv University and senior physician (retired) Dept of Medicine, Tel Aviv Medical Center.