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Owing to the general aridity of the region, a very large portion of the total area consists of endoreic or inland drainage. The Jordan River, the third largest perennial river in the Middle East, receives most of its discharge from precipitation on the southern part of the Anti-Lebanon range.
The Jordan is a multinational river, flowing southwards for a total length of 228 km through Lebanon, Syria, Israel, and Jordan (figs. 2.28 and 2.29). It is already overdeveloped except for a winter flow in its largest tributary the Yarmouk River, which forms the present boundary between Syria and Jordan for 40 km before becoming the border between Israel and Jordan.
Fig. 2.28 The Jordan River basin
Fig. 2.29 The upper Jordan River system
In the absence of irrigation extraction, the Jordan system delivers an average annual flow of 1.85 x 109 m³ to the Dead Sea, equivalent to 2% of the annual flow of the Nile and 7% of the annual flow of the Euphrates. Twenty-three per cent of this discharge originates in pre 1967 Israel (Naff and Matson 1984).
The discharge that feeds into the upper part of the Jordan River is derived principally from groundwater flow through a group of karstic springs on the western and southern slopes of Mount Hermon (Jabel esh-Sheikh). There are three rivers in the headwaters of the north fork of the Jordan River: the Dan River, the Hasbani River, and the Banias River, of which the quality of water is excellent, with salinity less than 15-20 mg of chlorine per litre. The flow in the lower reaches of the system is supplemented by springs, but much of their contribution is so saline that they degrade the quality of the river flow, to the extent of several thousand parts per million of total dissolved solids at the Allenby Bridge near Jericho.
Few regions of the planet offer a more varied physiography or a richer mix of ethnicities, religions, languages, societies, cultures, and politics than the Middle East. At the same time, no segment of the globe presents its diverse aspects in such an amalgam of conflicts and complexities. Out of this compound, one issue emerges as the most conspicuous, cross-cutting, and problematic: water. Its scarcity and rapid diminution happen to occur in some of the driest sectors of an area where there are also some of the fiercest national animosities. River waters in the Middle East are thus a conflict-laden determinant of both the domestic and external policies of the region's principal actors. Equally, though, they could be a catalyst for lasting peace.
As water shortages occur and full utilization is reached, water policies tend to be framed more and more in zero-sum terms, adding to the probability of discord. The severity of Middle Eastern water problems will, unavoidably, increase significantly year by year. In an already over-heated atmosphere of political hostility, insufficient water to satisfy burgeoning human, developmental, and security needs among all nations of the Middle East heightens the ambient tensions. By the end of the 1990s, Israel, Jordan, and the West Bank will have depleted virtually all of their renewable sources of fresh water if current patterns of consumption are not quickly and radically altered. In these circumstances, the Jordan River system, which includes the Al-Wuheda dam scheme on the Yarmouk River, unquestionably holds the greatest potential for conflict.
Despite the endless political complications in the Middle East, there is a recent history of tacit, although limited, cooperation over multinational river development even among the bitterest opponents. Israel, before its invasion of Lebanon and its troublesome stand on clearing out obstructions to the intake of Jordan's East Ghor canal, had more or less agreed informally to share the Jordan River system within the framework of the 1955 Johnston Plan.
The largest water-resource development project in Israel has been the National Water Carrier, which is a huge aqueduct and pipeline network carrying water from the Jordan southwards along the coastal region. The water is pumped from the En-Sheva intake in the northwest of Lake Tiberias at an elevation of 210 m below sea level to a height from which it flows by gravity to a reservoir at Rasalom. The installed capacity of the En-Sheva pumping station was 360 million m³ per year in 1968, and it could conceivably be increased to a maximum level of 500 million m³ per year, which is 90% of the Jordan's inflow of 544 million m³ per year at the inlet to Lake Tiberias (Beaumont et al. 1988). Such cutting of fresh-water flows in the upper Jordan River would, however, have seriously adverse effects on the quality of Lake Tiberias and its lower reaches by increasing salinity. The Mediterranean-Dead Sea canal and pumped-storage schemes in Lake Tiberias and the Dead Sea, described in chapter 5, are the key techno-political alternatives.
Israel currently uses as much as 90% or more of the stream water from the upper Jordan River. Jordan's water problems have undoubtedly been exacerbated by Israel's actions to deny it the right to develop fully the water resources of the Jordan River within its borders. The problem is particularly acute over the postponement of construction of the Al-Wuheda dam on the Yarmouk River. The upper Jordan has already been developed to a maximum capacity. The Al-Wuheda dam would complete development of the Yarmouk.
There have been several changes in the Israel-Arab situation since the Iraqi invasion of Kuwait in 1990. From integrated hydrological studies on the Jordan River system, it is now possible to conceive a comprehensive development plan that will be not only technically and economically feasible but also politically desirable and urgent. The Mediterranean-Dead Sea conduit scheme and the Al-Wuheda dam project could now be discussed simultaneously without threatening new political conflicts but rather to promote peace and economic development for the Palestinians. Discussion can now be based on a sense of the water cycle, in the context of hydrology, energy, and politics.
The following section describes the hydrology and water resources of the Jordan River system. Discussion of opportunities for integrated planning for comprehensive water-resource development is given in chapter 5.
2.5.1 The river basin
The catchment of the Jordan River, excluding its upper basin, is an integral part of the arid to semi-arid region (see fig. 2.28). There is a marked spatial variation in the distribution of precipitation over the catchment since the recharge area is confined to the mountainous areas of the Anti-Lebanon range, where the mean annual precipitation amounts to 1,400 mm, and the climate in the lower reaches of the Jordan in the Rift valley is arid to hyper-arid, with an annual mean precipitation of less than 50-200 mm.
The Jordan originates in the south-western Anti-Lebanon range, on the slopes of Mount Herman, which is covered with snow in winter. It then flows through Lebanon, Syria, Israel, and Jordan for a total distance of 228 km along the bottom of a longitudinal graben known as the Rift valley, or Ghor, before emptying into the Dead Sea. Its principal tributary, the Yarmouk, forms the border between Syria and Jordan and divides Israel from Jordan in the Yarmouk triangle. The lower reaches of the Jordan River border on part of the Israelioccupied West Bank to the west and Jordan to the east for a distance of about 80 km.
The catchment area of the Jordan is 18,300 km² in total, of which 3% lies in pre-1967 Israel. The lower Jordan River between Lake Tiberias and the Dead Sea has a catchment area of 1,050 km².
The Jordan River system may be classified on the basis of hydrology, hydrogeology, and water use into three sections: (1) the upper Jordan-headwaters, the Huleh valley, and Lake Tiberias; (2) the Yarmouk River; and (3) the lower Jordan-the main stream and the Dead Sea.
2.5.2 The upper Jordan
The upper Jordan River system includes (1) the three major headwater streams, the Dan, Hasbani, and Banias, (2) the Huleh valley, and (3) Lake Tiberias, or the Sea of Galilee (see fig. 2.29).
THE DAN RIVER. The largest of the springs is the Dan spring, which rises from Jurassic carbonate rocks and supplies a large and relatively steady flow that responds only slowly to rainfall events. The average discharge of the spring is 245 million m³ per year, varying from 173 million to 285 million m³. The Dan typically accounts for 50% of the discharge of the upper Jordan.
THE HASBAN RIVER. The Hasbani River derives most of its discharge from two springs, the Wazzani and the Haqzbieh, the latter being a group of springs on the uppermost Hasbani. All of these springs rise from subsurface conduits in cavernous Cretaceous carbonate rocks. Their combined discharge averages 138 million m³ per year but the values vary over a greater range than those of the Dan spring; over a recent twenty-year period, the flow of the Hasbani varied from 52 million to 236 million m³ per year. The Hasbani discharge responds much more rapidly to rainfall than does that of the Dan spring.
THE BANIAS RIVER. The Banias River is fed primarily from Hermon springs that issue from the contact of Quaternary sediments over Jurassic limestone in the extreme north-east of the Jordan valley. The average discharge of the Hermon springs is 121 million m³ per year; during a recent twenty-year period it varied from 63 million to 190 million m³.
The Dan spring, the largest of the sources of the upper Jordan, lies wholly within Israel close to the border with Syria. The spring sources of the Hasbani River lie entirely within Lebanon. The spring source of the Banias River is in Syria. These three small streams unite 6 km inside Israel at about 70 m above sea level to form the upper Jordan River.
Together the springs provide more water than can be accounted for as a result of rainfall over their immediate watersheds; thus, it is surmised that they represent the outflow of a large regional aquifer. The combined outflow of the springs and the precipitation that falls on the surface watershed of the upper Jordan is of the order of 500 million m³ per year. In a typical year, these karstic springs provide 50% of the discharge of the upper Jordan River; the rest is derived from surface run-off directly after the winter rainfalls. In dry years, spring outflow may make up as much as 70% of the flow of the upper Jordan. Table 2.5 summarizes the mean annual discharges of the three rivers.
Table 2.5 Annual discharge of the headwater rivers of the upper Jordan
|River||Riparian states||Flow (million m³)|
|TOTAL||504||298 - 711|
Source: Naff and Matson 1984.
Table 2.6 Water budget of the Huleh valley
|Inflow into valley||504|
|Plus local run-off from Huleh to Jisr Banat Yaqub||140|
|Minus irrigation in valley||-100|
|Outflow into Lake Tiberins||544|
Source: Naff and Matson 1984.
HULEH VALLEY. The flow of the upper Jordan enters the Huleh valley (formerly Lake Huleh), where it is augmented by the flow of sub-lacustrine springs. Among the minor springs and seasonal watercourses contributing the flow of the upper Jordan, the most important is the Wadi Bareighhit. The water budget of the Huleh valley is shown in table 2.6.
LAKE TIBERIAS. Beyond the Huleh valley, the north fork of the Jordan falls 200 m to Lake Tiberias (the Sea of Galilee), which lies 210 m below sea level. The upper Jordan contributes an average of 660 million m³ per year to the lake, or 40% of Israel's total identified renewable water resources. An additional 130 million m³ per year enters the lake as winter run-off from various wadis and in the form of discharge from sublacustrine springs that contain high salinity. Table 2.7 summarizes the water budget of Lake Tiberias.
Lake Tiberias has a volume of 4 x 109 m³, which is 6.5 times the annual inflow from the upper Jordan and 8 times the annual outflow. The water depth is 26 m on average, with a maximum of 43 m. The surface area is 170 km², which loses about 270 million m³ of water per year by direct evaporation. The salinity of the lake varies from a low of 260 mg to a high of 400 mg of chlorine per litre; this variation depends primarily on the flow of the upper Jordan, in which salinity does not exceed 15-20 mg of chlorine per litre (Naff and Matson 1984). About 500 million m³ leaves Lake Tiberias per year via its outlet and flows south along the floor of the Dead Sea Rift for about 10 km to the confluence with the Yarmouk River.
Table 2.7 Water budget of Lake Tiberias
|Inflow into lake||544|
|Plus rainfall over lake||65|
|Plus local run-off||70|
|Plus springs in and around lake||65|
|Minus evaporation from lake surface||-270|
|Outflow to lower Jordan||474|
Source: Naff and Matson 1984
2.5.3 The Yarmouk
The Yarmouk River originates on the south-eastern slopes of Mount Hermon in a complex of wadis developed in Quaternary volcanic rocks. The main trunk of the Yarmouk forms the present boundary between Syria and Jordan for 40 km before it becomes the border between Jordan and Israel. Where it enters the Jordan River 10 km below Lake Tiberias, the Yarmouk contributes about 400 million m³ per year (Huang and Banerjee 1984).
There is no flow contribution from the part of the valley where Israel is a riparian. Of the 7,242 km² of the Yarmouk basin, 1,424 km² lie within Jordan and 5,252 km² within Syria. The flow of the Yarmouk is derived from winter precipitation that averages 364 mm per year over the basin (Naff and Matson 1984). The stream flow is supplemented by spring discharges from highly permeable zones in the lavas; some further spring discharges may be channelled to the surface on wadi floors via solution pathways in the underlying limestones.
The mean annual flow discharge is 400 million m³, which is 65% of the total discharge of 607 million m³ per year from the Jordan's East Bank. The flow is largely influenced by the rainfall pattern in the Mediterranean climate, indicating a maximum monthly discharge of 101 million m³ in February and a minimum of 19 million m³ in September (Huang and Banerjee 1984).
The salinity of the Yarmouk River is quite low, being between 280 and 480 mg of total dissolved solids per litre.
EAST GHOR MAIN CANAL PROJECT. The Yarmouk's mean annual discharge of 400 million m³ provides almost half of the surface water resources of the Jordan River. After allowing for some 17 million m³ per year for downstream users in neighbouring countries, this water is diverted through the East Ghor Main Canal, an irrigation canal running along the Jordan River, to provide for agricultural water needs in the Jordan valley (fig. 2.29). The upper phase of the canal was completed in 1964, and by 1979 it had reached a length of 100 km, which could permit the irrigation of 22,000 ha (Beaumont 1988).
AL-WUHEDA (MAQARIN) STORAGE DAM SCHEME. The Al-Wuheda dam, first conceived in 1956, would be built in the northern part of Maqarin, about 20 km north of Irbid, to store the waters of the Yarmouk River. The estimated stream flow at the Maqarin gauging station is 273 million m³ per year on average, which includes flood waters being discharged to waste. On the basis of a bilateral riparian agreement between Syria and Jordan in 1988, preliminary work for opening an 800-metre-long diversion tunnel was completed by the end of 1989. The dam reservoir would have a gross capacity of 225 million m³, with effective storage of 195 million m³ annually. The water would irrigate an additional 3,500 ha in the Jordan valley, and supply 50 million m³ of water a year to the Greater Amman area and the eastern heights. It would also generate an average of 18,800 MWh of electricity a year. Syria would use part of the water and 75% of the total hydroelectric power generated by a power station near the dam. However, this project was stopped by Israeli opposition over waterallocation problems.
2.5.4 The lower Jordan River and the Dead Sea
South of its confluence with the Yarmouk, the Jordan flows over late Tertiary rocks that partially fill the Rift valley. For the first 40 km the river forms the international boundary between Israel and Jordan; south of that reach, it abuts the Israeli-occupied West Bank of the Jordan, where it forms the present cease-fire line. The Jordan here flows through the deepest portion of the Rift valley to enter the Dead Sea at 401 m below sea level, the lowest point on earth.
Run-off from winter rainfall within the valley is carried to the Jordan River via steep, intermittent tributary wadis incised in the wall of the Jordan valley, primarily on the East Bank. This source represents an additional 523 million m³ per year, of which only 20% originates in Israel; 286 million m³ is derived from perennial spring flow, while 237 million m³ is provided by winter rainfall (Naff and Matson 1984). The main tributaries on the East Bank, including the Zarqa River and Wadis Arab, Ziqlab, Jurm, Ubis, Kafrain, Rajib, Shueib, and Hisban are described in chapter 4.
The quality of the lower Jordan is influenced both by rainfall patterns and by the amount of base flow extracted upstream. Water salinity is about 350 mg of total dissolved solids per hire in the rainy season, while it rises to 2,0004,000 mg per litre in the dry season at Allenby Bridge near Jericho. Finally, the salinity of the system reaches 250,000 mg of total dissolved solids per litre in the Dead Sea, a level approximately seven times as high as that of the ocean. This salinity level is too high to sustain life, but certain minerals such as potash and bromines can be extracted by solar evaporative processes.
The Dead Sea covers an area of over 1,000 km² at a surface elevation of 400 m below mean sea level. It has two basins, separated by the Lisan Straits, the northern basin with an area of 230 km² and the southern basin with an area of 720 km². The catchment area is 40,000 km², including parts of Israel, Jordan, and Syria. The shortest distance between the Dead Sea and the Mediterranean Sea is 72 km (fig. 2.28).
The Dead Sea is a closed sea with no outlet except by evaporation, which is very high, amounting to 1,600 mm per year. In the past, the evaporation losses were replenished by an inflow of fresh water from the Jordan River and its tributaries, as well as other sources such as wadi floods, springs, and rainfall. The mean volume of water flowing into the sea before 1930 was about 1.6 x 109 m³ per year, of which 1.1 x 109 m³ were carried by the Jordan (Weiner and Ben-Zvi 1982). Under these conditions, the sea had reached an equilibrium level at a height around 393 m below sea level, with some seasonal and annual fluctuation due to variations in the amount of rainfall. However, since the early 1950s, Israel and later Jordan have taken steps to utilize the fresh water flowing into the Dead Sea for intensified irrigation and other purposes, which has reduced the amount of water entering the sea by 1 x 109 m³ per year. Consequently, the water level has declined in recent years to 403 m below sea level today, almost 10 m lower than its historical equilibrium level. The surface area of the Dead Sea and the volume evaporated from the surface vary only by a few percentage points between elevations from -402 to -390 m, while the water levels fluctuate considerably.
2.5.5 Water allocation problems and international riparian agreements
In 1953 the four countries Lebanon, Syria, Israel, and Jordan agreed in principle on the priority use of Jordan River waters, in the so-called Johnston Agreement, which provided for priority use of the main stem of the Jordan River by Israel and Lebanon, while the biggest tributary, the Yarmouk. running along the national boundary, was to be exclusively used by Syria and Jordan. This established a water allocation of the usable Jordan River estimated at 1.38 x 109 m³ per year in total: 52% (720 million m³) to Jordan, 32% (440 million m³) to Israel, 13% (180 million m³) to Syria, and 3% (40 million m³) to Lebanon (Naff and Matson 1984). It is widely assumed that the technical experts of each country involved in this discussion agreed on the details of this plan, although soon afterwards the governments rejected it for political reasons.
With the failure of these negotiations, both Israel and Jordan decided to proceed with water projects situated entirely within their own boundaries. As a result, Israel began work in 1958 on the National Water Carrier, which is currently abstracting 90% or more of the flow from the upper Jordan River through their intake in the north-west of Lake Tiberias.
Syria continued implementation of small-to-medium size dam development schemes for the upper Yarmouk. These plans could lead to increased salinity levels in the lower Yarmouk and lower Jordan Rivers, lower water levels in the Dead Sea, and reduced irrigation water for Jordan's East Ghor development project. From a strategic point of view, this long-term Syrian effort could reduce Jordanian access to the Yarmouk, on which Jordan relies to irrigate the Jordan valley, and may affect downstream availabilities for Israel. Ultimately, the possibility of heightened tension or even armed conflict among the riparians might increase (Starr and Stoll 1987).
The 1988 protocol of understanding between Jordan and Syria paving the way to renewing work on the Al-Wubeda dam project as part of a multinational master plan for development of the water resources of the region is described in chapters 4 and 5.
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