Comparison of WEAP and SWAT models for streamflow prediction in the Hadejia-Nguru Wetlands, Nigeria

Hadejia-Nguru Wetlands (HNWs) is listed as Ramsar wetlands of international importance due to its ecological functions, wild-life biodiversity and socio-economic importance. Accurate streamflow prediction is very important for decision-making in water resources planning and management of the wetland. Two semi-distributed hydrological models, Water Evaluation and Planning (WEAP), and Soil and Water Assessment Tool (SWAT), were used for streamflow prediction in the HNWs that is located within the Hadejia-Jama’are-Komadugu-Yobe Basin, Nigeria. Precipitation and temperature data from 1980 to 2016 were obtained at stations around the wetlands. Likewise, data on streamflow from 1980 to 2010 were collected and used as input to the hydrological models. The models were calibrated (1980–2000) and validated (2001–2010) against the observed streamflow over the periods at three-gauge stations. The performance of the models was compared using Nash–Sutcliffe Efficiency (NSE), Percent Bias (PBIAS) and Root Mean Square Error—Observations Standard Deviation Ratio (RSR). Results of WEAP and SWAT simulation yielded very good performance in terms of NSE (> 0.75) and RSR (< 0.50) at both calibration and validation periods. PBIAS for both model simulations also indicated satisfactory performances at validation period in two out of the three-gauge stations. Both WEAP and SWAT performed well for streamflow prediction thus demonstrating their suitability for streamflow prediction in the HNWs.