Programme Poster session 1 abstract 749
Groundwater resources in Jordan Valley: an integrated approach to the
hydrogeological investigation of unconsolidated aquifers
Author(s): M. Toll, Elias Salameh, Martin Sauter
Prof. Dr. Salameh:
Department of Applied Geology, University of
Jordan, 11942, Amman, Jordan
Prof. Dr. Sauter
Applied Geology, University of Göttingen,
Goldschmidtstr. 3, 37077, Göttingen, Germany
Keyword(s): integrated approach,
groundwater resources, semi-arid, Jordan, unconsolidated aquifer, numerical flow model, impact of climate change
Session: Poster session 1
Abstract In semi-arid areas groundwater systems are frequently not
sufficiently characterized hydrogeologically and long term data records are generally not available. Long-term time
series are necessary, however to design future groundwater abstraction scenarios or to predict the influence of future
climate change effects on groundwater resources. To overcome these problems an integrated approach for the
provision of a reliable database based on sparse and fuzzy data is proposed. This integrated approach is
demonstrated in the lowermost area of the Jordan Valley.
The Jordan Valley is part of the Jordan Dead Sea
Wadi Araba Rift Valley, which extends from the Red Sea to lake Tiberias and beyond with a major 107 km sinistral
strike-slip fault between the Arabian plate to the east and the northeastern part of the African plate to the west. Due
to extensional forces a topographic depression was formed. As a result of an arid environment it is filled with
evaporites, lacustrine sediments, and clastic fluvial components. A subtropical climate with hot, dry summers and
mild humid winters with low amounts of rainfall provide excellent farming conditions. Therefore the Jordan Valley is
considered as the food basket of Jordan and is used intensively for agriculture. As a result hundreds of shallow wells
were drilled and large amounts of groundwater were abstracted since groundwater is the major source for irrigation.
Consequently groundwater quality decreased rapidly since the sixties and signs of overpumping and an increase in
soil salinity could clearly be seen.
In order to achieve a sustainable state of water resources and to quantify the
impact of climate change on water resources a proper assessment of the groundwater resources as well as their
quality is a prerequisite. In order to sufficiently describe the complex hydrogeologic flow system an integrated
approach, combining geological, geophysical, hydrogeological, historical, and chemical methods was chosen. The
aquifer geometry and composition is described with the help of geological, hydochemical, and geophysical methods.
As far as the water budget is concerned, the recharge to the considered aquifer is estimated with geological methods
and available data sets, while the abstraction from the aquifer is estimated with the help of remote sensing techniques.
A historical approach is used to detect the general conditions under which the groundwater system has been in the
past. Afterwards this information is implemented into a flow model. On the basis of the findings a numerical 3-D
transient model integrating all important features of the hydrogeological system was developed In order to be able to
give reliable predictions about the impacts of climate change scenarios on the groundwater system the flow model
was tested against stress periods depicted during the historical review of the test area.. These stress periods include
periods of intense rainfall, of drought, and of anthropogenic impacts, like building of storage dams and of violent
conflicts. Recommendations for future sustainable groundwater abstractions are given.