UMAR Shamsuddeen Bello (B.Eng. WREE, A.B.U)2023-09-212023-09-212019-01-11https://teras.ng/api/asset/document/f456d4db-2151-43e8-95cb-2f7a417d2b7dhttps://teras.ng/catalog-item/fc88f937-c240-4b19-9a18-939f578e76e0http://dspace.teras-network.net:4000/handle/123456789/9537This study focused on application of physically based hydrological model, Soil and Water Assessment Tool (SWAT) interfaced with ARCGIS software over the Kangimi dam sub- watershed, located in Kangimi river sub-basin, in Igabi Local Government Area, about 37km away from Kaduna metropolis, Kaduna State, Nigeria.The watershed was delineated with 10 sub-basins, 39 hydrological response units (HRUs) were defined, which are areas with similar land use, soil, and slope characteristic, the watershed has a total surface area of 349.94km2 and a corresponding perimeter of 156.82km.The maximum and minimum elevation in the study area were determined to be 784m and 512m respectively.The program SUFI-2 in SWAT-CUP package was used for sensitivity analysis, the parameters found to be most sensitive are curve number (CN2), threshold water depth aquifer (GWQMN) followed by, soil available water capacity (SOL_AWC),groundwater delay time (GW_DELAY), groundwater „„revaporation‟‟ coefficient (ESCO), effective hydraulic conductivity (SOL_K) and base flow alpha factor (ALPHA_BF.gw) as relative to the determination of surface runoff.The model was executed from 1979 to 2014using SCS curve number method for estimation of surface runoff, Hargreaves method for potential evapotranspiration and Variable-storage method for channel routing.The calibration and validation of the model produced good simulation results based on the objective functions (p-factor=0.77, r-factor=0.71) and (p-factor=0.83, r-factor=0.75) for calibration and validation respectively, after achieving 500 simulations. The model performance was evaluated and found to be very good for both calibration and validation period of historical discharge datawith R 2 and NSE to be 92% and 82%, for calibration, and 93% and 86%, for validation respectively. The watershed hydrology was simulated in response to different LULC and climate changes, the surface runoff, evapotranspiration, contribution of groundwater to surface runoff, deep aquifer recharge and total average annual water yield at the watershed outlet for the simulation period were 387.37mm, 509.3mm, 248.22mm, 15.19mm and 655.51mm respectively. This interesting performance obtained with the ArcSWAT model suggests that SWAT model could be a promising decision support tool for sustainable management of water resources.Post Graduate Theses