ABSTRACT

This study presents an overview of electrical resistivity survey carried out within lkwuano/Umuahia area and its environs. There has been prevailing shortage of potable water supply in Umudike and efforts made toward ameliorating the situation through groundwater supply system are not meeting the desired results. There are many cases of rampant borehole failure within the study area. While some boreholes give out very poor yield at certain periods of the year, many others go dry right from the time of inception. The environs of Umudike as used here refer to places which fall within twenty kilometres radius (20km) from the location of Michael Okpara University of Agriculture, Umudike. Invariably, this is the enclave formerly called Ikwuano/Umuahia where this problem of failed boreholes is common. Reason(s) for this un-welcomed situation began to give people food for thought. Embracing the challenge, vertical electrical sounding (YES) technique using Schiumberger array was employed to carry out thirty (30) electrical resistivity surveys to acquire primary data together with ninety-two (92) resistivity data -J sets of existing boreholes (both productive and non-productive) procured as secondary data. Acquisition of global positioning system (GPS) data at VES/borehole locations was also done and incorporated with resistivity data for proper and in-depth investigation. Among several considerations to make, geology of every station was taken into account for verifying (in details) the nature, depth and thickness of the aquiferous zones where they exist. Results from the study reveal that two types of aquifers were investigated. The nature of the first is sandy aquifer while the other is sandstone aquifer. The total drill depths (TDD) of productive boreholes range between 68 and 125 metres. Thickness of the aquifers ranges from 89 to 326 metres. The major reason attributed to unsuccessful boreholes from this work is lack of hydrogeological and hydrogeophysical knowledge of the area. Other reasons include quackery and non-adherence to professional advice. The area under investigation has also been demarcated into borehole "NO-GO-AREA" and productive borehole zone to help prospective borehole owners/drillers within this environment.