Research Information System
IAH 50th Worldwide Groundwater Congress, Cape-Town, South Africa, 18 - 22 September 2023, pp.1
This paper presents the
results of groundwater flow modeling studies that were conducted within the
scope of the PRIMA RESERVOIR project. The main goal of the project is to
develop an innovative methodology to mitigate land subsidence due to excessive
groundwater exploitation in water-stressed Mediterranean watersheds. This
objective is achieved by integrating earth-observation derived land subsidence
rates with a coupled implementation of numerical groundwater flow and
geomechanical modeling. MODFLOW-based 3-D transient flow models were
constructed for the four pilot sites (the coastland of Comacchio in Italy, the
Alto Guadalentín aquifer in Spain, the Gediz River basin alluvial aquifer in
Turkiye and the Azraq basin in Jordan) that have different hydrogeological properties
and pose different challenges concerning water management. Models were
calibrated and run for similar simulation periods (2013-2021) to obtain hydraulic
head drawdowns and change in groundwater storage. Land subsidence at these
sites were evaluated using Advanced Differential Radar Interferometry
(A-DInSAR) on image stacks from the Sentinel-1 satellite. Subsidence rates were
then compared to rates of hydraulic head drawdown to identify areas of
groundwater pumping induced subsidence. The comparison for all study areas suggested
that locations of maximum displacements do not necessarily coincide with areas
that display the largest head drawdown as calculated by the flow models. Other
triggering factors such as the thickness of compressible materials are also
related to high subsidence areas.