In the case of lean years, Israel may face a serious water shortage. The Water Commission is making a number of strategic changes in the Israeli water sector, with regards to seawater desalination. Thanks to improved technologies, it is possible to produce high-quality water, at a relatively cheap cost
Dr. Yosef Dreizin, Scientific American
The country's water systems were designed in the first years of its existence, and with the establishment of the national carrier in 1964, the nature of the water economy was determined until recently. The natural water sources, which include the Kinneret basin and the aquifers (groundwater), were connected together. The water pumped in the north is pumped south. The central water is connected to them, and while supplying the consumers, the system provides what is needed all the way to the south of the country, in Be'er Sheva and the Negev Mountains. "Mekorot" - the national water company, is responsible for supplying water to anyone who needs it, operates according to the guidelines of the Water Commission, and guarantees benign water quality according to the regulations of the Ministry of Health for drinking water quality.
The main water consumers are domestic consumers and agriculture. Additional consumers - industry, nature and later also the Palestinians and the Kingdom of Jordan, most of them are fed by the national system. About 40% of the natural water that is not part of the Mekorot company's system is pumped and supplied by private production and supply systems. These water sources are usually pumped from the same sources of the national system. The Water Commission believes in coordinating utilization based on professional considerations and according to its responsibility as derived from the Water Law.
In the 70s, the water shortage increased due to the dwindling sources. The water industry began to make intelligent use of domestic sewage, while turning it over for quality effluents for agricultural and industrial use. Thus, Israel became an example and the standard bearer of the integration of wastewater in the balance of water needs of the economy.
Change in policy
The policy according to which the water system was managed in those years, and in fact until the beginning of this decade, determined that the natural reservoir, in the Sea of Galilee and in the groundwater, should be allowed to absorb the maximum possible nutrition in the winter, and it is desirable that the winters be rainy. The guiding logic was that the more we allow more rain to accumulate in the natural reservoirs, the more we will reduce the losses due to overflows, and in total we will maximize the multi-year amounts of water for utilization. This is a policy of "walking on the edge". Along with the benefits of keeping free volumes to absorb excess rains in rainy seasons, there was the risk and fear that a regular supply would not be possible following a fallow year or a series of such years. This policy was also supported from the economic aspect, when the production of additional water, beyond the natural supply, is considered expensive, and cutting agriculture is preferable to any other solution.
Israel is geographically located in a semi-desert region. The difference between rainy years and dry years is expressed in the climate, the extent of the rains, their intensity and their distribution. The presentation of the refilling of the natural reservoirs in the last 70 years illustrates the variation and frequency of relatively long series of wet years, compared to short series of rainy years.
In the years 1999 to 2001, as already happened in the past, the hydrological system fell into a crisis, which was even intensified due to the policy described here. The water quotas for farmers were radically cut, and they still believed that if the year 2002 were to be the same, there is a real fear that the water sector would not be able to meet the minimum needs, including drinking water.
The Israeli government was alarmed, following the warnings of the Water Commission, and already in 2000 ordered the start of operations to desalinate sea water. At the beginning of 2002, the Water Commission prepared a master plan (transition) for the water sector, which was intended to present necessary actions to "save" the sector. At the foundation of the program was established an alternative policy, "responsiveness to needs". The water sector is required to propose the actions and carry them out to ensure the water needs outlined by the government. Security of supply with maximum reliability obliged the planners to propose broad development plans to be carried out by the end of the current decade.
The master plan examined the water balances against the stated needs. The inventory was presented both in terms of averages and from considerations of probabilities for different scenarios. It was determined that agriculture will be based on an "iron ration" of benign water, and most of its needs will be met from the supply of wastewater. The hydrological system will only be exploited if it can ensure sustainability and prevent deterioration as a result of over-exploitation. The benign water systems will be upgraded with the addition of produced water and the adaptation of the networks to the distribution of the supply. The significant result of the plan is a series of development projects until the end of the decade with an estimated amount of NIS 20 billion. About 50% of the investment volume is intended to go to the private sector.
The sea water desalination plan, along with the other actions proposed in the master plan, provides a central framework for action. The volume of desalination of about half a billion cubic meters per year has been set as an upper threshold value, which we will reach if a dire forecast is realized according to which the region may be damaged by a series of dry years. Two relatively blessed years have changed the plan, at least in terms of the rate of development. The initial decision made in 2002 established a seawater desalination quota for development with an immediate scope of 400 million cubic meters per year (mcmh). The plan was reduced to 315 mm/h, and this plan is indeed being carried out now.
The economic factor - as a main influencer
The economic factor that helped the decision-making process in this matter should not be ignored. Seawater desalination costs have decreased considerably in the previous decade. It was found that relatively large facilities, where improved technologies will be used, will produce quality water at a cost that will be lower than 50 cents per cubic meter. Although this cost is higher than the production cost of natural water, the superior quality of desalinated water largely offsets the additional cost.
A fundamental issue was already determined in the first stage after the decision was made to integrate seawater desalination into the system. It was decided to establish the projects through the private sector. It was agreed with the company "Mekorot" that it will build a single project for the supply of 45 ml/h in Ashdod. A tenders committee headed by the Deputy Accountant General was appointed. The committee operates with the assistance of consultants. The state contracts with developers using the BOT (land owned by the state) or BOO (land owned by the developer) method for 25 years. The price of water is determined in a tender, and the state undertakes to purchase the water at a rate that is divided between a fixed basic payment according to the availability of the facility, and a payment for the water supplied. The sites designated for the establishment of desalination facilities, including the volumes of water for production and the relationship with the supply systems were determined within the framework of a national outline plan (TAMA 34 b).
All facilities connect to the national water system and integrate into it. We are dealing with an important water source, which will increase the supply of sources by more than 20% in the current development phase. We assume that the national system can absorb up to 500 million cubic meters per year, when moreover, in the future, strengthening of the national carrier will be required. The flow directions that were initially planned from north to south will change, according to the seasons, when the desalinated water comes from the west, and part of it will flow north.
The quality of the water produced in the desalination facilities will be extremely high, and will actually improve the quality of the water supplied to most water consumers. The low salinity, the controlled hardness, and the unconditional compliance with the regulations of the Ministry of Health for drinking water are a tremendous advantage to support the absorption of this water.
All in all, the Water Commission's initiative to respond to the needs of a modern water system is heartbreaking. We anticipate that we will be able to guarantee water to anyone who needs it in quality, quantity and reliability for years.
Dr. Yosef Dreizin serves as the chairman of the Desalination Administration after establishing and managing the planning department at the Water Commission for more than a decade
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