Well and Formation Losses in Boreholes Constructed in a Weathered Crystalline Basement Aquifer in Nigeria
In this paper, we present the results of a study on well and formation losses in three new public water supply boreholes drilled in a weathered granitic aquifer in Nigeria using data obtained from step drawdown tests conducted to assess the potential yields of the wells.
Our results show a mean yield of 2.93 l/s for the three wells and this compares with values reported for similar formations in other regions of the world. Well losses increased with pumping rates for individual wells and contribute between 5.2% and 70.54% of the total drawdown of the wells studied. Recommendations for minimizing well losses and hence total pumping costs are made.
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