Evaluation of aquifer storage potentials and groundwater level fluxes require analysis of groundwater recharge and discharge rates. Volumetric groundwater budget of the recharge and discharge of the shallow unconfined aquifer system of Benin-City and environ have been simulated using a three-dimensional groundwater flow and a particle-tracking models. This is with a view to elucidating groundwater storage potential water level fluctuations in the area. Nine burrow pit exposures and thirty borehole logs were also studied. Well correlation and geologic cross-sections of the subsurface geology culminated in hydrostratigraphic model, and determination of saturated thickness and lateral extent of aquiferous units. Burrow pit exposures revealed occurrence of surficial reddish lateritic cover underlain by laminated loose sands varying in colour with clay and clayey-sand intercalations. Annual groundwater level fluctuations were 0.85 - 1.25 and 0.82 to 1.60 meters at Ikpoba and Ogba respectively. Thirty-year period groundwater recharge rates from precipitation and river leakage were 0 to 1.075 x 105 m3/day and 02.737 x 105 to 1.114 x 106 m3/day respectively. Groundwater discharge rates through baseflow and evapotranspiration rates were 1.165 x 104 to 4.219 x 106 m3/day and 7.486 x 105 to 3.715 x 107 m3/day respectively. The cumulative groundwater recharge rates (2.73 x 108 m3/day) exceeded the discharge rates (5.07 x 107 m3/day). Hence, the aquifer has very high storage potentials.
Borehole data, groundwater modelling, groundwater recharge, Niger Delta, trend analysis
Joshua Oluwasanmi Owoseni "Simulation of storage potentials and trend analysis of water level in shallow unconfined aquifer system of Benin-City and environ, southern Nigeria." Iconic Research And Engineering Journals Volume 6 Issue 6 2022 Page 299-312
Joshua Oluwasanmi Owoseni "Simulation of storage potentials and trend analysis of water level in shallow unconfined aquifer system of Benin-City and environ, southern Nigeria." Iconic Research And Engineering Journals, 6(6)