Hydrological Modeling of Tubo Watershed, Kaduna State using ArcSWAT Model

Abstract

Hydrological models have been used to model the processes of the watershed which could serve as a decision framework for harnessing alternative water supply source. The simulation was carried out, for the most important hydrology parameters such as precipitation, evaporation, runoff, infiltration, percolation and evapotranspiration respectively, using Soil and Water Assessment Tools (SWAT) model which is integrated with ArcGIS software. The study location was Tubo Watershed along Tubo river, a sub-basin of Kaduna basin in Igabi local government area which is about 42km away from Kaduna metropolis towards the northern part of Kaduna
state, Nigeria. The model was run for the period from 1979 to 2014 with calibration using field measured discharge data of watershed for four years (1983-1986) and validation performed for two years (1987-1988) respectively. Moreover, the monthly simulated runoff of Tubo watershed for the calibration and validation periods were found to match with their measured discharge value of coefficient of correlation (R2) for both which are 0.80 and 0.73 respectively. Furthermore, the model simulated daily runoff is collaborated by reasonably high Nash-Sutcliffe simulation coefficients (ENS) of 0.81 and 0.50. Based on the recommended statistical coefficients, the model evaluation indicated a very .....