In this research, an Electromagnetic (E.M) method of groundwater investigations was used as an on-spot assessment tool to test the integrity of the  developed borehole in Afe Babalola University, Ado-Ekiti. Some randomly selected functional and abandoned boreholes developed by the Vertical Electrical Sounding (VES) methods were chosen for this study, with the aim to know the potential of the boreholes. Four transverses were  established across the institution consisting of two functional and two abandoned boreholes selected from the existing forty boreholes. These weresubjected to E.M method of groundwater investigation using a PQWT S500 series machines. The results obtained from this study produced curve graphs and subsurface profile maps of each transverse location. It was observed that boreholes TR 1 and TR 3, were accurately sited on vertical fractures and weathered formations while TR 2 and TR 4 were wrongly sited at the locations of poor groundwater yielding zone. Keywords: Electromagnetic, Vertical electrical Sounding, transverse, Groundwater.

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With the large inter-annual variability of rainfall in Northern Nigeria, a zone subject to frequent dry spells which often result in severe and widespread droughts, the need for intense study of rainfall and accurate forecast of rainfall intensity duration frequency (IDF) curves cannot be over emphasized. The Intensity Duration Frequency relationship is a mathematical relationship between the rainfall intensity and rainfall duration for given return periods. Using a subset of the network of fifteen continuous auto recording rain gauges available in Northern Nigeria, a total of seven different time durations ranging from 12 minutes to 24 hours were developed for return periods of 2, 5, 10, 25, 50 and 100 years. The maximum data series so obtained was fitted to Gumbel’s Extreme Value Type 1 distribution. Linear Regression Analysis was then used to obtain the intensity-duration relationships for the various locations from which Intensity-Duration Frequency (IDF) curves were generated using Microsoft Excel for various return periods. Keywords:  Extreme rainfall, intensity, duration, frequency, Northern Nigeria

This research was carried out with the aim to check the validity and efficiency of the existing groundwater potential map of Afe Babalola University, Ado Ekiti (ABUAD). The performance rating of the drilled boreholes that spread across the institution was used to validate the groundwater potential map produced by Ademilua and Eluwole in 2013. Forty (40) boreholes that were drilled in the institution were evaluated and overlaid on the existing groundwater potential map with their coordinates serially numbered. From the results obtained, it was observed that in locations designated as having good to moderate groundwater yield (potential) on the map, 21 of drilled boreholes were active, 11 were failed/dry boreholes, meanwhile, for the locations designated as having poor groundwater yield, four of drilled boreholes were active while another four were failed/dry boreholes. This result gives a 62.5% performance rating that the existing groundwater potential map can serve as a useful guide for the purpose of site selection for groundwater exploitation but for optimal usage, an improved map is required.