Quantity and Quality Modeling of Groundwater Flow in Shahrekord Aquifer

Groundwater resources, as one of the most important factors in sustainable development, need to be intensely considered. Numerical models such as Modflow and MT3D is an applied tool for simulation and management of groundwater flow and solute transport. In this study, Shahrekord aquifer modeling is provided by the use of monthly data’s including hydraulic heads, depletion volume of the wells, springs and qanats, precipitation values. This model has been developed based on the assessment of the hydraulic conductivity and specific yield coefficients in the calibration process. The study year was divided to 12 monthly stress period for calibration (10 periods) and verification (2 periods). The results showed that the hydraulic conductivity from 6 to 16 m/day and specific yield from 0.03 to 0.07 were varied. The predicted water table in calibration process in comparison to observed values of water levels on piezometers with variance of 0.63. These results confirm the need model of groundwater flow prediction. Moreover, Effective molecular diffusion coefficient, longitudinal dispersity and distribution coefficient were calibrated to achieve acceptable variance between observed and calculated nitrate concentration. The most contaminant particles are in the south zone of aquifer where is the nearby urban wastewater wells. Moreover, the central and south parts of plain have the suitable situations for groundwater discharge because of the high amount of transmissivity.