Overview of Middle East Water Resources
Surface Water
Wadi Wala
The course of the Wadi Wala runs from its headwaters
south of Amman in the Jordan Highland and Plateau
at about 700 m above sea level, to its confluence
with the Wadi Mujib about 3 km from the Dead Sea
and over 300 m below sea level - more than 1 km
lower than the headwaters. The central and northern
areas of the watershed comprise the fertile plains
around Madaba where the average annual rainfall is
300-400 mm, and the average annual potential
evaporation is about 2,200 mm. In its lower reaches,
the Wadi Wala is known as the Wadi Heidan. The
drainage area of the Wadi Wala-Heidan is about
2,000 km 2 at its confluence with Wadi Mujib.
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Course of Wadi Wala across
Jordan Rift Valley Escarpment
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Flow characteristics of the Wadi Wala are measured
at Karak Road, where the drainage area is 1,800 km2 .
The Wadi Wala has fairly stable baseflow that typically
provides from 0.1 MCM per month during the
summer to more than 1 MCM per month during
the winter, as shown in the graph of median monthly
volume to the right. The drainage area of the Wadi
Wala at Karak Road is less than half that of the
Wadi Mujib at Karak Road; however, baseflow of the
Wadi Wala is slightly greater than that of the Wadi
Mujib. This is mainly because average annual rainfall
in the Mujib watershed is about one-half that of the
adjacent Wala watershed. Zero flow conditions have
been observed at the Karak Bridge gage during
summer months in only 3 years-1990, 1995, and
1996. The largest observed floods on the Wadi Wala
occurred in April 1971 and February 1992, with
discharges of 245 and 248 m3/s, respectively.
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Hydrographs. Left: Median annual volume by watershed. Right: Annual volume, 1964-96.
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Water Data Banks Project,
Multilateral Working Group on Water Resources,
Middle East Peace Process
Overview of Middle East Water Resources
Information about this document.
