long term simulation of shazand plain aquifer under changing resources and applications

iran is among the world’s arid and semi-arid regions and its demand for water has been increased due topopulation growth, urbanization and the development the economic sectors (industrial and agricultural). inmany of these regions, the lack of planning and the unauthorized use of resources have led to excessiveexploitation and a lower level of groundwater. the usable groundwater for the country water supply is about55 percent. research has been carried out for modeling the shazand groundwater, which is located inmarkazi province. modeling has been carrying out using visual modflow software. in recent years shazandaquifer groundwater levels have dropped significantly. groundwater level during 8 years (1998-2006) was0.84 m and the annual average 0.105 m has also fallen. population, urbanization and increasing migration inthis region have resulted in higher demand for water which its only solution is inevitably limitedconsumption in the agriculture sector through efficiency improvement. the model execution results for thesetwo options reveal that efficiency improvement will increase the basin hydrograph about 3.4m during an 8year period with 0.42 m annual average. increasing population trends during a 10 year period have resultedin 2.5m reduction in the water table level with annual average of 0.23 m. according to planning horizon anddrinking water supply, final results indicate that the stability of aquifer resources without othercomplementary resources depends on more limited agricultural usage through the improvement of efficiencyand irrigation methods.