Currently, over 700 million people do not have access to sufficient supplies of clean water. Many regions suffer severe water stress, i.e. draw on 80% or more of their renewable water resources. About 44% of the world population live within a 150 km wide shoreline belt susceptible to flooding by the encroaching ocean and sea water intrusion into the groundwater resources. Global recharge of the fresh water resources is a finite quantity originating from the unevenly distributed atmospheric precipitation and is vulnerable to the climatic changes. For example, countries in the Middle East and North African region receive as little as 1% of the world’s precipitation of which 85% is lost through evaporation. World Resources Institute predicts that by the year 2040 at least 33 countries will endure acute to severe water stress. Time honored practice of carrying water from distant “water-rich” and less populated regions via costly aqueducts, canals, pipelines etc. to water-thirsty regions has been proven not a solution, but only a temporary remedy as recently demonstrated by the California drought.
Israel, located in one of the most water-stressed regions of the world has recently demonstrated a long-term, if not permanent solution to its water scarcity. Until about 2010 Israel was rapidly depleting all renewable water resources. It was clearly losing the battle with the sea water intrusion into the coastal aquifer. The glorified 130 km long National Water Carrier added less than 500 million cubic meters of water a year – less than a third of Israel’s water usage at the time of its peak performance – causing lateral environmental and political damages, e.g. a drastic fall in the level of Lake Tiberias (The Sea of Gallilee), that in turn caused increased inflow of saline springs through the Lake bottom, causing rise in lake water salinity; decline in the flow rates and increase in salinity of the lower Jordan River; the enormous damage to the Dead Sea due to the vast decrease in the amount of water entering it from the Jordan River and, last but not least, the conflict with Syria and Jordan over water.
The Israeli solution consists of the water triad: desalination, recycling and optimization of the irrigation methods. Sixty percent of the Israeli agricultural land is irrigated by highly efficient drip irrigation. Israel produces 500 million cubic meters of wastewater every year, more than 90% of which reaches the various treatment plants. Currently, Israel utilizes 85.6% of the wastewater it processes (highest in the world, compared to the second-highest 12% in Spain, 9% in Australia, 5% in the USA and 1% in Europe). Israel’s desalination capacity has currently reached 560 million m3/year with some of the world’s largest sea water reverse osmosis facilities, lowest costs (less than $0.40/m3) and numerous innovations. The Israeli water triad should be considered a valid pilot project, particularly for the countries located within the areas characterized by high water stress index.