HYDRAULIC TRANSMISSIVITY DETERMINATION FOR THE GROUNDWATER EXPLORATION USING VERTICAL ELECTRIC SOUNDING METHOD IN COMPARISON TO THE TRADITIONAL METHODS

An important aquifer characteristic, transmissivity significantly contributes to the development of local and regional groundwater resources and solute transport management. Estimation of this property allows quantitative prediction of the hydraulic response and solute transport of the aquifer to recharge and pumping. This study presents the three techniques, used to compare transmissivity determination by Vertical Electric Sounding (VES) over the traditional techniques. The validation of VES was compared with the old widely used methods such as grain size distribution and pumping test techniques. Grain size distribution analysis was carried out to determine transmissivity. Pumping test was performed to determine transmissivity using the type curves solution for unconfined aquifer and taking into account the delayed yield. In resistivity imaging survey, the soil layers were detected through interpretation of resistivity data. Formation factor for each layer was determined with the relation of aquifer soil resistivity and ground water resistivity. The estimated transmissivities though grain size distribution, pumping test and resistivity survey were 0.588, 0.578 and 0.756m^2/min, respectively. The results emphasized the potential of the resistivity survey for aquifer transmissivity determination.