Saman Javadi - Department of Irrigation and Drainage Engineering, Aburaihan campus, University of Tehran, Tehran, Iran
Hamid Kardan Moghaddam - Department of Water resources research, Water research institute, Ministry of Energy, Tehran, Iran
Aminreza Neshat - Department of GIS/RS, Faculty of Natural resources and Environment, Science and Research Branch, Islamic Azad University, Iran

Quantitative changes in groundwater and crises resulting from uncontrolled water extraction have turned water resources management into one of the supply-demand dilemmas in arid regions. The present study evaluated the quantitative situation of water resources in the Ardestan Plain adjoining the Ardestan desert by using the MODFLOW mathematical model. Simulation of groundwater flow in the steady and non-steady states was carried out for a six-year period. Considering the trend of uncontrolled water extraction, results of the simulation also showed that there was a groundwater-level decline in the middle parts of the aquifer and smaller in its western parts. Analysis of the groundwater flow and the water resources balance in watershed basin indicated that in the outlet section of the aquifer the groundwater flow direction was reversed. Given the groundwater-level decline in the aquifer, the groundwater level was higher in the desert section and caused groundwater transfer from the desert to the aquifer. This suggests that the Ardestan aquifer will have environmental problems in its outlet section in addition to problems resulting from lack of water resources management and from the decline in groundwater level. This transport can increase with the continuation of the exploitation trend and also influence a larger part of the aquifer. Consequently, the results of the present research revealed that considering the recent droughts, groundwater extraction must be managed in order to improve the quality and quantity of water in desert aquifers.

Aquifer, modeling, Hydraulic gradient, Groundwater flow direction, MODFLOW