Investigation of the Effective Factors on the Subsidence in Tehran South-East Plain Due to Excessive Groundwater Exploitation

Abstract

Land subsidence is amongst the issues that occur due to excessive groundwater exploitation, causing deep gaps in the ground, tilting of wells and collapse of buildings. In most areas of the country, the main reason for this phenomenon is water table draw-down, which is caused by the lack of rainfall due to climate change and excessive exploitation of groundwater. In this paper, in order to investigate the effective factors on the subsidence in the South-East plain of Tehran, various stations in this area have been studied and numerically modeled using the finite element method. GEOSTUDIO software has been used to analyze the geotechnical and hydraulic data in the region in comparison to the results of previous studies. The results indicated that the level of water changes and depth of drilled boreholes had an effect on the amount of land subsidence, and with decreasing water recharge to groundwater table, the subsidence rate increased by up to 55%. Also by increasing the percentage of changes in water exploitation, the subsidence rate was increased by about 40%.

Keywords

• finite element method
• ground subsidence
• south-east tehran plain
• groundwater exploitation
• water return