Overview of Middle East Water Resources
Groundwater Basin Summaries
![[small map]](images/p19_loc.gif)
Jordan Valley Floor Basin
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Well 19-13/069, near Jericho, is a typical well com-pleted
in geologic unit Q 2 . Water is obtained from
sand and gravel in several intervals between the
depths of 75 and 114 m, with a water level about
31 m below land surface and test yields between
12 and 30 L/s. Well yields in the basin typically
vary from 3 to 70 L/s.
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The Jordan Valley Floor Basin is located in the
floodplain of the Jordan River south of Lake
Tiberias. The entire basin is contained in the Jordan
Rift Valley, a pronounced geologic depression in
which elevations range from 210 to 400 m below
sea level. The basin is underlain by alluvial deposits
of soil, sand, and gravel of geologic units Q1 and Q2 ,
and marl, clay and evaporites of the upper part of
unit Q2 that infill the rift valley to a thickness of at
least 2,200 m.
Groundwater is recharged by precipitation at an
average volume of 21 MCM/yr. Because the quality
of water from the Jordan River is generally poor,
groundwater is the principal source of freshwater
in the basin. About 80% of the fresh groundwater is
present in the alluvial fans of the major side wadis
(geologic unit Q1 ). Potential freshwater aquifers
occur mainly as lenses of sand and gravel within
marl of the Lisan Formation (unit Q2 ), or as sand
and gravel deposits in the alluvial fans. The
remaining 20% of freshwater sources are withdrawn
from sand, sandstone, and limestone of geologic
units Kk and Ja, particularly in areas where these
units are recharged along the foothills of the eastern
and western escarpments.
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Groundwater levels in parts of the basin have
shown a long-term decline in response to
pumpage as illustrated in well 19-15/023
near Jericho. Increases in chloride and nitrate
concentration appear to be related to water-
level fluctuations.
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Groundwater levels vary greatly in the Jordan Valley
Floor Basin, with depths ranging from 5 m in the
central part of the valley to 150 m at the escarpment
foothills. In parts of the basin, a major concern
is a rising water table due to irrigation return flows,
that could potentially result in increased soil salinity.
Groundwater quality in the basin is variable. In the
southern part of the basin, water is slightly brackish
with chloride concentrations ranging from 700 to
1,850 mg/L; whereas, in the northern part of the
basin, the water is somewhat fresher with concentrations
Water Data Banks Project,
Multilateral Working Group on Water Resources,
Middle East Peace Process
Overview of Middle East Water Resources
Information about this document.
