SIMULATION OF GROUNDWATER FLOW USING MODELMUSE (MODFLOW) AND INTEGRATION WITH GIS-BASED GROUNDWATER POTENTIAL ZONES IN OTUKPO AND ENVIRONS, BENUE STATE, NORTH CENTRAL NIGERIA
Groundwater scarcity in Otukpo and environs, Benue State, Nigeria, is exacerbated by overexploitation, population growth, and climate variability in the Lower Benue Trough sedimentary basin. This study integrates 15 Vertical Electrical Sounding (VES) surveys (Schlumberger array, AB/2 up to 217 m), 15 pumping tests (Theis method), GIS-based multi-criteria groundwater potential (GWP) zonation using Analytic Hierarchy Process (AHP), and steady-state numerical modeling with Model Muse/MODFLOW. VES data inverted in IPI2WIN and pumping tests analyzed in AQTESOLV yielded hydraulic conductivity of 7.59–54.09 m/day (mean 29.35 m/day) and transmissivity (T) of 145.83–1,167.50 m²/day (mean 740 m²/day), with strong correlation (R = 0.998). GIS-AHP weighted overlay (incorporating K, T, thickness, depth, slope, and elevation) classified the area as 35.5% very high potential, 40.7% high, 17.5% moderate, and 6.2% low. A conceptual model informed a steady-state MODFLOW simulation (recharge 0.0005 m/day, 15 wells at 360 m³/day, constant head boundaries at streams). The model achieved 0.00% water balance discrepancy, simulated heads of 137.5–155.0 m (mean 142.5 m), and drawdowns of 0.5–1.6 m. Integration via zonal statistics and ANOVA (F = 395.2, p < 0.001) confirmed significant head variations across GWP zones. Recommendations include targeted borehole development (60–80 m depth, 360–500 m³/day abstraction) in very high zones. This first Model Muse application in the area provides a replicable framework for sustainable groundwater management in data-scarce sedimentary environments.
Authors : Omepa, C., Ankidawa, B.A., Tya, T.S.K., Inuwa, A.M., Usman, M.N. and Chataimada, J.
Category : Open Access Volume (Issue) : 12(1) Date Uploaded : 5th August 2026