Previous - Next
This is the old United Nations University website. Visit the new site at http://unu.edu
5.1 Background and objectives
5.2 Water resources of Israel
5.3 Water-resources development and management
in Israel
5.4 Joint Israel/Palestine/Jordan
Mediterranean-Dead Sea conduit development with co-generation
5.5 Integration of development alternatives in
an inter-state water master plan
5.6 Techno-political non-conventional
water-energy development alternatives in inter-state regional
planning for Aqaba
5.7 Techno-political alternatives in Middle East
water perspectives
5.1.1 Background
By the year 2000, water-not oil-will be the predominant resource issue of the Middle East. The situation will be particularly acute in non oil-producing countries such as Israel and Jordan, where the renewable water resources such as fresh surface waters and groundwater will have already been exploited or will soon be fully developed.
Concerns over the global environment and the Gulf (oil) crisis associated with Iraq's invasion of Kuwait in August 1990 have improved our understanding of the importance of clean energy such as non-polluting hydroelectric power.
A solar-hydro scheme using the evaporation power of the Dead Sea and known as the Mediterranean-Dead Sea (MDS) canal scheme was proposed by Israel in 1980. The scheme, which would have multiple socio-economic and political ramifications, was intended to convey water from the Mediterranean to the Dead Sea via canals and tunnels, utilizing the height difference of around 400 m to generate 600 MW of electricity. In addition, proposals were made to use the water for cooling nuclear power stations rated at 1,800 MW, and to investigate the feasibility of generating 1,500 MW from Dead Sea as a solar pond. Up till now there has been no presentation of the concept of sharing resources with riparian states and no effort at joint development. The MDS project was soon put aside, owing to strong opposition from Arab states and others and to confusion following the drop in world oil-market prices in 1984.
Major constraints to realizing the 1980 MDS project were:
>> Jordanian fears of environmental and economic effects-which may no longer be valid;
>> the failure to consider the concept of shared resources, including riparian rights to the Dead Sea, and the absence of any effort at joint development between the states-all of which could now be removed by linkage of the MDS and Al-Wuheda dam projects;
>> territorial questions on the West Bank-which, with cooperation with the Palestinians, could now be dealt with separately from cooperation in water development.
There have been several changes in the political situation since the Iraqi invasion of Kuwait in 1990-1991 that may facilitate a comprehensive resolution of Israeli-Arab problems. This may make integrated development not only technically and economically feasible but politically desirable and urgent.
5.1.2 Objectives
The objectives of this chapter may be stated as follows:
>> to delineate the strategic dimensions of water problems in one of the world's driest regions-Israel, Palestine, and Jordan-where the peace of the world has been at risk for more than forty-five years;
>> to evaluate the techno-political feasibility and cost-effectiveness of the proposed co-generation system for the MDS scheme, using hydro-power with seawater RO desalination to produce fresh drinking water for the interstate region of the Dead Sea;
>> to elaborate techno-political alternatives in the inter-state basin development master planning of the Jordan River system, by combining non-conventional alternatives with advanced water technologies;
>> to re-assess the much-discussed Mediterranean-Dead Sea conduit scheme, which has again been revived with the end of the Gulf war in 1992 and the international political drive for peace in the Middle East in 1993-1994 and an end to the Arab-Israeli conflict.
In an average year rainfall over Israel is estimated to be 5 x 109 m³; about 3.5 x 109 m³ of this is lost through irretrievable absorption evaporation, leaving only 1.5 x 109 m³ per year to reach the country's water reservoirs on the surface and underground (Gisser and Pohoryles 1977).
The characteristics of Israel's water resources may be summarized as follows:
>> Rain falls only in winter, with wide fluctuation, ranging from around 25% of the long-term average in dry years to 160% in particularly rainy years.
>> Most water sources are situated in the northern and central regions of the country.
>> Most water sources are located at low elevations, from which water must be pumped with high operation and maintenance costs.
Owing to the substantial fluctuations in annual rainfall, groundwater aquifers are conceived as more reliable potential reservoirs than surface storage. About one-third of Israel's water use is dependent on surface water resources, mainly the Jordan River. Groundwater is therefore a major source of supply, amounting to two-thirds of national consumption. The aquifers concerned are dependent on limestone formations 300-400 m thick and deep sandstone formations 600-800 m thick. The deepest groundwater wells penetrate to a depth of 1,000 m or more.
Marginal or non-conventional waters-brackish groundwater, seawater, and treated sewage effluents-are looked to mainly for additional water supplies for the next decade.
5.2.1 Potential water resources
Potential renewable water resources depend exclusively on precipitation, which, in addition to fluctuating considerably from year to year, has significant spatial variations. Over half of Israel receives annual rainfall of less than 180 mm, while it is 1,000 mm or more in the high mountains of northern Israel. Although renewable water resources accumulate in the north, the demand is concentrated in the central and southern regions. The rainy season begins in October or November and ends in April or May; for the rest of the year there is very little rain, three or four months being completely rainless. Replenishment of groundwater occurs exclusively in winter, while irrigation with its highest water demand occurs in the summer.
Of the average 1.5 x 109 m³ of rainfall reaching the country's surface and underground water reservoirs per year, the Sea of Galilee in the north stores effectively receives 0.5 x 109 m³, while aquifers in the coastal plain store 1 x 109 m³.
5.2.2 Surface water resources
Surface drainage is mainly provided by a few streams flowing east and west. Throughout the southern half of the state, streams are ephemeral.
About one-third of Israel's potential usable fresh water is surface water, which depends largely on the Jordan River. The river is entirely land-locked, terminating in the Dead Sea. Its hydrology and water resources have been discussed in section 2.5.
Galilee as a whole is the wettest region of the state, receiving in places over 1,000 mm of rainfall per year, and both springs and streams are more numerous than in other areas.
The northern Harod (Bet She'an) River, a tributary of the lower Jordan, is replenished by abundant springs or groundwater flow but has high salinity and is useless for irrigation purposes. Its brackish water is the major source of contamination of the lower Jordan. However, RO desalination promises to salvage 20 million m³ of water per year or more.
The Yarqon River is a short stream on the coastal plain fed by large springs at Rosh Ha'ayin, 15 km east of Tel Aviv. The Yarqon River basin lies on economic aquifers with high development potential.
The mountainous and hilly zones in Samaria and Judaea receive more than 500 mm of average annual rainfall, but surface water is not plentiful. The permeable strata dipping westward are valuable for groundwater recharge to the underlying potential aquifers.
5.2.3 Groundwater resources
The main aquifers to supply water for irrigation and municipal and industrial use are found in permeable strata of Cenomanian-Turonian carbonate rocks and Plio-Pleistocene sandstones.
Some of the main sources of groundwater are the thick carbonate rock aquifers of the Cenomanian-Turonian formations, which consist mainly of dolomite and limestone intercalating some clay and chalk layers. The total thickness amounts to 600-700 m in the central and northern parts of Israel. The aquifer supplies several hundred million cubic meters of water annually, which is a significant portion of Israel's water supply (Schneider 1967).
The coastal plain is rich in water resources from wells and springs. Up to 700 mm of precipitation may be received per year over the hills, and permeable strata dipping westward yield valuable groundwater for the coastal plains. This gave the early Jewish settlers a wide choice of sites for their villages, while today it is one reason why Israel wishes to retain control of the West Bank as a major source of groundwater recharge. The aquifer lies at depths of 18-120 m in the Middle Plio-Pleistocene formation. Groundwater abstraction from the coastal aquifer amounts to around 30% of the total water supply volume in Israel (Beaumont et al. 1988).
5.2.4 Non-conventional water resources
The marginal waters of Israel are composed primarily of brackish water, seawater, and urban waste water. The potential contribution of marginal waters to meet the anticipated water demand include the following alternatives:
>> reclaimed sewage effluents of the Dan region (Greater Tel Aviv), >> water harvesting for the Sea of Galilee by artificial rainfall,
>> brackish waters to the north of the Sea of Galilee and in the south in the area adjoining the port town of Eilat on the Red Sea,
>> seawater desalination,
>> peak-demand power generation by seawater pumped storage by the Dead Sea,
>> RO desalination of water with co-generation of power for peak demand needs, by the Mediterranean-Dead Sea conduit scheme,
The salinity of the brackish groundwaters in the north near Lake Tiberias and in the south in the area adjoining the port of Eilat on the Red Sea is in the range of 1,000-10,000 mg of total dissolved solid (TDS) per litre, which is suitable for desalination by RO at a reasonable cost. The M&I water supply for Eilat is heavily dependent on the RO desalination of this brackish groundwater. Renewable supplies from the underlying aquifers have been estimated at about 200 million m³ per year (Buras and Darr 1979). Seawater desalination by distillation such as by the multi-stage flash (MSF) process used in the Gulf states is still too expensive for non-oil-producing countries such as Israel and Jordan.
The second source of marginal water is urban waste water, for which the demand has been increasing since the late 1970s and early 1980s. On the basis of returnable useful flows of 65 % of domestic and 30% of industrial water consumption, the urban waste-water potential for 1985 was estimated at 370 million m³ (Buras and Darr 1979).
Evaluation of the marginal waters in a national water master plan will be needed, taking into account recent innovative research on saline water conversion, including the desalination of brackish water and seawater by the ROprocess.
5.2.5 Water consumption in Israel
Almost all renewable water resources such as surface water in the upper part of the Jordan River and groundwater in the limestone and deep sandstones aquifers, of which the potential supply is preliminarily estimated at 1.5-1.6 x 109 m³ per year, were already being exploited by the end of the 1970s. Indeed, the demand had already exceeded the potential of renewable resources by the late 1960s. Annual water consumption in Israel was 1,565 million m³ in 1973, including 1,180 million m³ (75.4%) for agriculture, 288 million m³ (18.4%) for domestic use, and 97 million m³ (6.2%) for industry. It was then predicted that by 1992 water-resource development to provide a further 8.1 million m³ for agriculture, 20.5 million m³ for domestic use, and 28.5 million m³ for industry would be needed (Buras and Darr 1978).
Israel's per capita consumption (537 m³ per year; 86 m³ per year for domestic purposes only) is not out of line with other industrial nations, although it is as much as double that of its neighbours (Naff and Matson 1984). The agricultural sector is responsible for more than three-quarters of Israel's total water use.