Shallow borehole and dug well data are used in describing groundwater conditions in the vicinity of\r\nAbraka in the Nigerian coastal plain. Drill cuttings from ten boreholes show that the Abraka area is\r\nunderlain by reddish brown unconsolidated sands, followed by a succession of grey- off-white medium\r\ngrained sands of the Benin Formation. Hydraulic conductivity estimated from grain size analysis of\r\ncuttings obtained from typical borehole screened horizons range from 0.12 to 0.19 msec-1. Regional\r\ngroundwater flow is from north east to southwest with local distortions on this regional trend resulting\r\nfrom ground water abstraction in densely populated areas. Maximum TDS in ground water was\r\nrecorded at 28 and 85 mg/l from dug wells. The trilinear plots of major ions in water indicate a mixing of\r\nmainly sodium chloride and calcium chloride water types. The stiff diagrams are also suggestive of\r\npossible stratification of water chemistry with depth. Borehole water quality is well within WHO and\r\nNigerian drinking water quality standards while that from dug wells contains minimal levels of fecal\r\ncoliform. Ground water and surface water are determined to be suitable for irrigation. It is also shown\r\nthat the quality of water in the River Ethiope, TDS 6.6 to 8.09 mg/l, Escherichia coli occurrence at less\r\nthan an average of 50 cfu/100 ml from selected recreation sites meets WHO standards for body contact\r\nrecreation.
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