Assessment of application the artificial recharges methods of aquifer of Imamzadeh Jafar plain in Gachsaran-southwest of Iran

Before feeling water -shortage crisis human has understood the importance of water From the religious texts. Considering recent conditions of the world the water will replace most recent boundaries, at future. Imamzadeh Jaafar plain is located 5 kilometers northeast of Gachsaran, south of Kohgilooye and Boerahmad province. The plain has 61km 2 area extents and contains two, alluvial and carbonate aquifers. These aquifers supply the water needs, agricultural, industrial and domestic. Highly exploitation and transportation of groundwater resources, especially by National Oil Company, caused highly drawdown in alluvial aquifer, 1.85m in a 5 years period from 1361 to 1365 as reported by Mahab Ghods Consulting Engineers. There are two artificial recharge projects, 1 flood spreading system and 1 recharge ponds system, in the plain. To present the future water resources management program the hydrogeological behaviors of the alluvial aquifer and the effects of artificial recharge must be evaluated. To develop the conceptual model of aquifer required information, meteorological, water level in the observation wells, depth to bedrock, hydrodynamic coefficients, topography, water resources and …, were collected, field surveys were performed and required maps were prepared. Using conceptual model and MODFLOW PMWIN code the mathematical model of the plain was calibrated against water year 13 -81 and then verified against water year 1384 - 85. The verified model was used to predict future conditions of aquifer. The results implied the rapid response of aquifer to precipitation due to high aquifer transmissivity, positive water budget at year 1385 comparing year 65, change of direction of groundwaterflow from plain outlet to the center of plain in response to highly exploitation at the center of plain, water level in the wells located downward the flood spreading system will raise as to 6m and water level in t he wells located downward the recharge pond system will lower as 1 to m.