Mapping of Groundwater Flow Pattern: A Case study of JUI and Allen Town Community, Sierra Leone

Abstract

The groundwater mapping procedure that was employed in this research is a process which was done basically to delineate flow direction, identify possible recharge and discharge areas and generate groundwater maps that will provide useful information on its use and sustainability. A study was carried out at Jui and Allen Town Community, located in the eastern part of Freetown using the global positioning system (GPS) and a Dipmeter to determine the groundwater flow pattern of the area. The longitudes, latitudes and elevations of fifty (50) hand dug wells or borehole locations distributed within the study area were measured and recorded. The depths to the water level in the hand-dug wells were measured directly with the aid of a Dipmeter. A computer based software package known as Surfer was used to generate a water elevation contour map of the study area which revealed that groundwater flow direction is from the West to the Eastern part of the area. It is therefore recommended that dumpsites should be sited within the south or south-eastern part of the area while boreholes for potable groundwater exploitation could be sited in the north, east and western regions in order to minimize groundwater contamination. From the results obtained in this study in relationto flow direction and its implication regarding the vulnerability of groundwater to pollution, it can be seen that the east and south-eastern parts of the area or aquifer is more susceptible to pollution. Therefore, communities within the North, West and Southern regions of Jui and Allen Town Community should take steps to ensure that land use activities will not pose a threat on the quality of groundwater. The present study act as a guide for future groundwater exploration, hence the information will be useful to both the Government of Sierra Leone and other individuals particularly those in water industries in sinking and maintaining boreholes for optimum groundwater exploitation.