Assessment of Economically Accessible Groundwater Reserve and Its Protective Capacity in Eastern Obolo Local Government Area of Akwa Ibom State, Nigeria, Using Electrical Resistivity Method

Abstract

The application of geophysical method employing vertical electrical sounding (VES) method in combination with laboratory analysis of aquifer sediments has been used to access the economically accessible groundwater reserve and its protective capacity in some parts of Eastern Obolo Local Government area, the eastern region of the Nigerian Niger Delta. Schlumberger electrode configuration was used to sound twelve VES to occupy the areas that have borehole locations and accessibility for the spread of current electrodes to at least 1000 m. Based on the results, the safe and economic aquifer potential has groundwater reserve of about 168480558 ± 18532861 m 3 . The desired aquifer thickness and its depth of burial have average value of 52.02 m and 73.14 m, respectively. The area has a fair protective capacity. This is indicated by 58.33% weak, 16.67% moderate, and 25% good protective capacity for the area. This study was done in one of the oil cities, where contaminated Salt River water is used as the major source of water for domestic uses and it is believed that the settlers will appropriate this result and sue for safe groundwater at the indicated depths.