The Effect of Geofiltration Heterogeneity of Bottom Sediments on Groundwater Discharge in a Small River Basin under Natural and Disturbed Conditions

A regional model of a small river basin with a catchment area of approximately 1000 km 2 is considered. The model was developed to evaluate the possible influence of groundwater intake on river runoff. The model is calibrated to the measured levels of groundwaters and discharges of this river. Geophysical and hydrometric surveys have allowed us to characterize the heterogeneity of the conductivity of the bottom sediments along the riverbed. The reduction in the river discharge considering this heterogeneity is greater by 25% than the reduction in the discharge calculated without taking it into account. Thus, consideration of the heterogeneity of bottom sediments for more reliable estimation of an influence of water intakes on the environment is recommended.