Hydrological Modeling of an Ungauged River Basin Using SWAT Model for Water Resource Management Case of Kayanga River Upstream Niandouba Dam

Hydrological modeling of ungauged basins is important and imperative for policymakers and stakeholders in water management. The Kayanga river upstream from the Niandouba dam is subject to extreme pressure caused by natural and anthropogenic factors. The hydro system Niandouba Dam and Confluent Dam are used to providing water for the irrigated perimeters in Anambe. Since there is no data available to evaluate the water resources entering the Niandouba Dam, we used Soil and Water Assessment Tools (SWAT) to set up a hydrological model in the ungauged basin of Kayanga river upstream Niandouba dam. A regionalization approach has been used to predict the river discharge at Niandouba watershed upstream of the Niandouba dam. SWAT model has been calibrated from 01/01/2001 to 31/12/2001 and validated from 01/01/2002 to 31/12/2002, with a daily scale on the Koulountou watershed. During the calibration period, the criteria of goodness of fit are respectively 0.87 for Nash-Sutcliffe Efficiency coefficient (NSE), 0.87 for coefficient of determination (R2), -1.6% for Percent Bias (PBIAS) and 0.36 for Standard Deviation Ratio (RSR). In the validation period, we have found a Nash-Sutcliffe Efficiency coefficient (NSE) of 0.62, a coefficient of determination (R2) of 0.77, a Percent Bias (PBIAS) of +35.9%, Standard Deviation Ratio (RSR) of 0.62. These parameters have been used to generate flows at the entrance of the Niandouba Dam.