Abstract: Eight vertical electrical sounding data sets were obtained from various parts of the study area, located within latitudes 5°05''N and 5°37''N and longitudes 7°00''E and 7°30''E in the middle Imo River Basin. The litho-stratigraphic unit of Benin formation was investigated. The sounding data were analyzed with the RESIST Software to delineate the sub-surface layering. The concept of Da-Zarrouk parameters (transverse unit resistance and longitudinal conductance in porous media) was used to determine aquifer hydraulic characteristics. The following values of hydraulic conductivity and transmissivity were obtained for the Benin formation, K_mean = 23.07 m day^-1; T_mean = 704.72 m² day^-1; K_max = 46.97 m day^-1; T_max = 2036.21 m² day^-1; K_min = 7.02 m day^-1; T_min = 87.05 m² day^-1. It was established from the study that thick productive aquifers are located in the Benin formation.