Hydrogeological Characteristics of Groundwater Yield in Shallow Wells of the Regolith Aquifer: a Study from Ilorin, Nigeria

Abstract

Present paper tries to understand the influence of hydrogeological characteristics on groundwater yield of shallow wells in regolith aquifer, Ilorin, Nigeria. The data on hydrogeological characteristics such as drawdown, water level, depth of borehole, depth of overburden and well yield for 78 borewells were collected from Kwara State Ministry of Water Resources and Lower Niger River Basin Development Authority in Ilorin. While the aquifer transmissivity and well specific capacity was calculated from this data. The data obtained were subjected to Pearson moment correlation, multiple and stepwise multiple regression analysis. The results of the stepwise multiple regression (R² of .929) indicates that aquifer transmissivity and drawdown contributed 92.9% to the variability in well yield in the study area. It is concluded that while constructing wells, aquifer transmissivity and the rate of drawdown be taking into account for the purpose of having productive well in the study area.

Keywords: Aquifer Transmissivity, Well Specific Capacity, Regolith Aquifer, Drawdown, Well Yield, Groundwater, Ilorin, Nigeria.