Forecasting of Subsidence due to groundwater over exploitation using MODFLOW and interferometry technique in Radar imagery

Fatemeh Jafari, Saman Javadi, Neamat Karimi

Thursday 2 july 2015

12:39 - 12:42h at Central America (level 0)

Themes: (T) Water resources and hydro informatics (WRHI), (ST) Catchment hydrology, Poster pitches

Parallel session: Poster pitches: 11H. WRHI - Catchment

Subsidence is one of disasters due from groundwater over exploitation. Aquifer compaction and land subsidence accompanying groundwater abstraction in susceptible aquifer systems in the Aliabad plain in center of Iran is a challenge for managing groundwater resources and provide hazards. Indeed, Subsidence is a permanent and irreversible phenomenon which will occurs in aquifer that groundwater level experienced a dramatic decrease. Land subsidence could occur because of groundwater over exploitation as a result of compaction in compressible soil layers. It is important to identifying the affected aquifer part and simulate groundwater flow and subsidence conditions in this area. Developments in the assessment of subsidence provide more information to constrain analyses and simulation of aquifer-system compaction. To simulating vertical aquifer compaction, such as those embodied in the aquitard drainage model and the MODFLOW subsidence packages, have proven useful from the perspective of regional groundwater resources assessment. In this research groundwater flow and aquifer compaction is simulated using MODFLOW and SUB package. Used in this research is interferometry technique in Radar imagery in order to measuring subsidence in the area during specific time of simulation. Base on result, 70cm subsidence occurs during 7 years namely 2003 till 2010. In addition, main subsidence observed in center of plain and also recharge zone of entrance. Base on model prediction this rate will reaches to 150cm in the next five years if the water exploitation remains in same situation. The only way to come over this problem would be more integrated water management in this area, which is vital to prevent any extra subsidence. Key Words: Groundwater Modeling, Subsidence, Radar image, aquifer-system compaction, MODFLOW