|Managing Water for Peace in the Middle East: Alternative Strategies (UNU, 1995, 309 pages)|
|5. Solar-hydro power and pumped-storage co-generation in hydro-powered reverse osmosis desalination in inter-state development of the Jordan River basin|
The primary users of the waters of the Jordan River are Israel and Jordan. Between them, the Jordan River system has been extensively exploited; it satisfies about half of their combined water demand. The other riparian states are Lebanon and Syria; their use of the Jordan River at present is minor as compared to the others, and satisfies about 5% of their total demand for water.
The most comprehensive water-resources development and management in the Middle East to date is undoubtedly found in Israel. Following the establishment of the state in 1948, the government decided to undertake a comprehensive programme of water-resource development based on the ideas outlined by Lowdermilk (1944; cf. Appendix C). Two factors had considerable importance in the initial stages of development: the first was the lack of capital in the new state, and the second was the urgent necessity to provide water supplies for the many immigrants pouring into the country.
Up to about 1965 and completion of the National Water Carrier, there was enough water awaiting development to satisfy all needs. All that was required was new schemes to tap the resources and make efficient use of them. From the late 1960s onwards it became extremely difficult to make any extra water supplies available, and so emphasis had to be shifted to making more eflicient use of the available supplies.
In the late 1970s and early 1980s Israel had to face a growing demand for water from the urban and industrial sectors of its economy. It will now have to face the issue of diverting water from the agricultural sector, which still accounts for more than three-quarters of the country's total water use, to the municipal and industrial sectors of the economy.
5.3.1 Initial stage of water-resource development
Initially, attention was concentrated on low-cost projects, such as the drilling of wells, which produced quick results. These pumped wells permitted the irrigation of new lands on the coastal plain and in the northern Negev.
Efforts were made by Jewish rural settlers to improve the flow of the upper Jordan River in the Huleh valley during 1950-60. The Huleh valley, situated in the northernmost corner of Israel, was a marshy area where nobody could live before the 1950s. The marshy area was flooded by the winter flow of the upper Jordan River, and the stored water evaporated without productive use in the semi-tropical climate. Land-reclamation work was carried out by the immigrants to construct a series of canal and drainage systems to control both flood water and the groundwater levels in the depressions, to enable them to convert the valley from a useless marsh into fertile irrigation land.
Development of the upper river basin in conjunction with irrigation and drainage of the Huleh valley, however, both increased the saline nutrient flows into Lake Tiberias (the Sea of Galilee) and has resulted in a heightened concern over eutrophication. The chloride ion concentration in the lake rose from below 300 to nearly 400 mg/l between the years 1949/50 and 1963164, as shown in fig. 5.1. The increased utilization of water resources may not have been the only cause of this sharp increase in salinity, but it is conceivable that it played a major role in it.
5.3.2 Medium-term water-resource development
Medium-term development projects were chosen that permitted the maximum investment per unit of water supplied, were not technically complex, and allowed the investment to be divided into a number of stages. At the same time, the idea evolved that every project within the country, no matter what its size, should be able to be integrated into a nationwide hierarchical water-supply system. A number of long-term projects that had a regional rather than local significance were also implemented.
The Yarqan-Negev project, which was one of the early schemes of the National Water Carrier and was completed in 1955, carries water from Rosh Ha'ayin springs and groundwaters east of Tel Aviv in the Yarqon River basin southwards towards the Negev desert. The system provides 270 million m³ a year for Tel Aviv and for irrigating the Lachish area (Naff and Matson 1984).
The Western Galilee-Kishon project was the first large-scale conjunctiveuse scheme for developing both surface water and groundwater. It carries 85 million m³ a year from western Galilee to the fertile but dry Jezreel Plain (Naff and Matson 1984). The water source is mainly surface water during the winter months, when it is relatively abundant, and groundwater during the drier summer period.
The Beit She'an Valley project, about 15 km south by south-west of Lake Tiberias, exploits a perennial stream whose water is too salty for either drinking or irrigation purposes but can be utilized by diluting it with purer water from Lake Tiberias.
5.3.3 Integrated development stage: the Israel National Water System
The largest water-resource development project in Israel is the National Water Carrier, a huge aqueduct and pipeline network carrying the waters of the Jordan River southwards along the coastal plain region (fig. 5.2). This scheme stems from earlier ideas and concepts for the integrated development of all the waters of the Jordan for the mutual benefit of the states of Lebanon, Syria, Jordan, and Israel.
In the early 1950s discussions took place between Israel and the adjoining Arab states in an attempt to reach an understanding as to how the waters of the Jordan River might be most fairly allocated among the four states. This resulted in a plan drawn up for the United Nations usually referred to as the Main Plan: 1953. After prolonged negotiations, modifications to the original plan were made, and the new version became known as the Johnston Plan: 1955, named after the American mediator, Eric Johnston. The potential use of the Jordan's water was estimated to be 1,287 million m³ per year in total, of which 31% was allocated for Israel, 56% for Jordan, 10% for Syria, and 3% for Lebanon. It is widely assumed that the technical experts of the various countries involved agreed on the details of this plan, though soon afterwards the governments rejected it for political reasons. (See Appendix C for further discussion of these plans.)
With the failure of these negotiations, both Israel and Jordan decided to proceed with water projects situated entirely within the* own boundaries. As a result, Israel began work on the National Water Carrier in 1958. The main storage reservoir, and also the starting point of the scheme, is Lake Tiberias. From there water is pumped through pipes from 210 m below sea level to a height from which it flows by gravity to a reservoir at Tsalmon. After a further lift, the water flows via a canal to a large storage reservoir at Beit Netofa, which forms a key part of the system. South of Belt Netofa, the water is carried in a 270-cm diameter pipeline to the starting point of the Yarqon-Negev distribution system at Rosh Ha'ayin. In the initial stages 180 million m³ of water was carried per year. The capacity was increased to 360 million m³ per year in 1968, and it is believed that the maximum capacity now approaches 500 million m³ per year (Beaumont et al. 1988). This has, however, not yet been attained owing to the salinity problems of Lake Tiberias. At present, the national water grid interconnects all the major water demand and supply regions of the country with the exception of a number of desert regions in the south. In total, it supplies approximately 1.4 x 109 m³ per year, or about 90% of all Israel's water resources. More than half of the water is obtained from the Jordan and its tributaries, with a further 14% from the Yarqon River basin.
5.3.4 Conjunctive use and groundwater management
Many of the main groundwater aquifers in Israel are integrated operationally within the National Water Scheme. The pumpage from these aquifers has to be coordinated with releases of water from surface sources. The conjunctive operation of surface reservoirs and aquifers has been carried out in conjunction with artificial groundwater recharge schemes. Owing to the scarcity of suitable surface storage sites and the arid climate with high potential evaporation, part of the aquifer system, composed of Turonian-Cenomanian carbonate rocks, has been used as an underground reservoir to store the excess of winter stream flows through pumping wells and/or recharge wells (Schneider 1967; Buras 1967).
5.3.5 Water conservation
The total annual water supply was about 1.75 x 109 m³ in 1988, approximately 74% of which is used for irrigation, 19% for domestic use, and 7% for industrial use (fig. 5.3). Approximately 43% of the cultivated land, or 185,000 ha, is irrigated. Present estimates indicate that Israel currently uses as much as 95% or more of its total renewable water resources, including both surface water and groundwater (Beaumont et al. 1988).
There have been spectacular achievements in agriculture, and today almost all irrigation in Israel is carried out by sprinkler, drip, or sub surface systems. This has meant that a given irrigated area can now be watered with much less water than previously. At the same time it does mean, however, that little future water savings can be made by agriculture by increasing efficiency, as irrigation in Israel is as economical in water use as any in the world.
In the late 1970s and early 1980s Israel had to face a growing demand for water from the urban and industrial sectors of its economy. Experiments have been made to reuse urban waste waters through the Dan Waste-Water Recovery project, but success has been less than had been hoped for owing to difficulties in removing contaminants from the waste water. Research into various water desalination systems has concluded that distillation, such as the dominant multi-stage flash process used in the Middle East, is too expensive except for specific projects.
The result has been that Israel has been faced with the fact that the only way to obtain water for growing cities is to divert water from one use to another. This requires facing the issue of diverting water from the agricultural sector, which still accounts for more than three quarters of Israel's total water use, to the municipal and industrial sectors, taking into account the net effect on the economy of the state.
What seems likely to happen increasingly in Israel, as has happened in parts of the United States such as Arizona, is that irrigated land adjacent to urban centres will be taken out of cultivation and the water diverted to urban and industrial uses. By the early decades of the twenty-first century almost all the countries of the Middle East region will be facing similar severe water shortages in urban centres as their populations continue to grow. It seems inevitable, therefore, that water will have to be diverted away from irrigation to urban/industrial uses. Israel has been starting to reduce national water use since 1987 by cutting the supply of irrigation water, as seen in fig. 5.3. It was announced that allocations of water for agriculture in 1991 would be reduced by 30% from the 1990 level, and it seems that this was achieved.
5.3.6 Israel's occupation policy and water resources of the West Bank
The occupied lands, most notably the West Bank and Golan Heights, are important to the water economy and security of Israel. It is estimated that one-third of Israel's water resources originates in rainfall over the western slopes of the West Bank and is drawn from the same aquifer system that supplies the West Bank. Hence the Israeli occupation of the West Bank since 1967 has allowed greater exploitation of this aquifer by preventing new water-resource development by the Arab population. The effect has been to maximize groundwater recharge so that the aquifer under Israel can be more extensively developed. At the same time, Israeli settlements in the West Bank are also tapping the aquifer.
It should also be noted that another one-third of Israel's water comes from the Jordan River. The 1967 conquests are important in this light also because the Golan Heights afford control over the upper Jordan, enabling Israel to block any Arab attempt to divert its headwaters (fig. 5.2). Almost half of Israel's total water supply therefore consists of water that has been diverted or pre-empted from Arab sources located outside its pre-1967 boundaries (Naff and Matson 1984).