Identification and Estimation of Nutritional Resources of Bojnourd Alluvial Aquifer in Order to Evaluate the Groundwater Balance
mina tajabadi
1
(
expert of groundwater/Hydrotech Toos Consulting Engineering compony
)
alinaghi ziaei
2
(
ferdowsi univesity
)
negar Farrahi
3
(
expert of surface water/Hydrotech Toos Consulting Engineering compony
)
elham beigzade
4
(
expert of water resources/ Hydrotech toos consulting engineering compony
)
Keywords: recharge, Aquifer, Wastewater, SWAT, MODFLOW,
Abstract :
increasing water demand followed by population growth and underdeveloped sewer network in the Bojnourd city, in addition to rising groundwater levels, has resulted in poor aquifer. Prevention of quantitative and qualitative reduction of groundwater and rising water level issues depend on proper management and groundwater protection. Effective water use management considers the investigation of aquifer stresses and management strategies. Hence, this study aims to estimate and evaluate the groundwater balance based on the identification and estimation of recharge resources with the help of the SWAT model, considering the losses of water distribution network and returned wastewater to the aquifer. On that account, the groundwater model was simulated and calibrated using MODFLOW model in GMS software in two steady and unsteady states for a thirteen-year period, and then the groundwater balance components were estimated annually for the period 2001-2014. The root mean square of the final model error in steady and unsteady states were 1.36 and 1.4 meters, respectively, hydraulic conductance with three optimal values of 7, 13 and 26 square meters per day and specific yield were estimated 0.02, 0.04 and 0.19. The NRMSE parameter indicates 19% of the fluctuations between the observed and calculated water level, which is due to inaccurate estimation of sewer network return flow and the leakages in water distribution network.