Hydro-‐political Baseline of the Upper Jordan River - Ibrahim Abd El Al

MC M/m
120.0
100.0
80.0
60.0
40.0
20.0
0.0
68-­‐69 69-­‐70 71-­‐72 72-­‐73 73-­‐74 02-­‐03 03-­‐04 04-­‐05 05-­‐06 06-­‐07 07-­‐08
Years
Figure 3.4 Hasbani River flows, measured at the Fardiss Bridge, 1968 – 1974, and 2002 – 2007,
showing the high inter-­‐annual and intra-­‐annual variability (LRA 2011). Note the spike in year 2002-­‐
2003 is not considered accurate, and attributed to issues with calibration of the gauging equipment.
3.2.2 Flows measured in Israel
Flow monitoring records of the Lake of Tiberias have been kept by the Hydrological Service
of Israel (HSI) have been kept since 1949, and are now gauged through nine different points
(see e.g. Givati and Lynn 2011). The striking difference in intra-­‐annual variability between
the three main tributaries is shown clearly in Figure 3.5.
The spikes of the discharge curves of the Hasbani and Banias reflect the rivers’
responsiveness to rainfall, while the steady core reflect groundwater-­‐fed ‘base flows’. In a
similar way, the smooth discharge curve of the Liddan further demonstrates the importance
of groundwater to that river, as annual changes are shown to have little influence. The
steady flow of the Liddan holds for inter-­‐annual variability, as Table 3.2 and Figure 3.6 show.
The average flow measured just upstream of the confluence of the 3 main Upper Jordan
River tributaries during the period 1949-­‐2004 for the Hasbani is 123 MCM/y, Liddan -­‐ 241
MCM/y, and the Banias -­‐ 114 MCM/y. The average flow of the Upper Jordan River at the
confluence of the three rivers is thus taken as 480 MCM/y. The annual discharge of the
Liddan is much more stable than those of the Banias and the Hasbani, rarely exceeding a
deviation of 10% below or above its average. By contrast, the Banias regularly deviates from
its average annual flow by 30%. The most extreme variations are observed on the Hasbani,
which regularly deviates by up to 40% from its average annual flow.
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