The Study of the Impact of Water Conveyed From Maneh Basin on Bojnourd Aquifer by Using GMS Model

Bojnurd plain is located in Atrak River’s watershed, North Khorasan province. The urban areas are covered more than 70% of the plain. It is supposed that the Bojnourd’s plain aquifer will be affected by the water conveyed from Maneh basin in order to supply drinking water. As the wastewater collection system has not been completed yet and the municipal drinking wells have been switched off, rising groundwater levels in some part of the urban areas is predicted. In this study the impact of developing urban wastewater collection system on Bojnourd aquifer was investigated using a mathematical model in GMS software. The data from October 2001 was selected to calibrate the values of the hydraulic conductivities in steady state. Then the model was calibrated from October 2001 to September 2011 in unsteady state and the values of storage coefficient and monthly recharge were optimized. Sensitivity analysis and verification of the model were performed using data from October 2011 to March 2013. Modeling results confirmed that the groundwater levels will be rised to ground surface in many parts of the urban areas, as the wastewater system is not completed. However, full development of the wastewater water collection system will relatively decrease the problem.