SWAT Literature Database for Peer-Reviewed Journal Articles

Title:Multi-dimensional evaluation of simulated small-scale irrigation intervention: A case study in Dimbasinia Watershed, Ghana 
Authors:Worqlul, A.W., Y.T. Dile, J.-C. Bizimana, J. Jeong, T.J. Gerik, R. Srinivasan, J.W. Richardson and N. Clarke 
Volume (Issue):10(5) 
Article ID:1531 
URL (non-DOI journals): 
Model:APEX & SWAT 
Broad Application Category:hydrologic only 
Primary Application Category:model and/or data interface 
Secondary Application Category:irrigation impacts or irrigation BMP scenarios 
Watershed Description:35 km^2 Dimbasinia River, located in the upper east Navrongo Region in northern Ghana. 
Calibration Summary: 
Validation Summary: 
General Comments: 
Abstract:This paper studied the impacts of small-scale irrigation (SSI) interventions on environmental sustainability, agricultural production, and socio-economics using an Integrated Decision Support System (IDSS). The IDSS is comprised of a suite of models, namely the Soil and Water Assessment Tool (SWAT), Agricultural Policy/Environmental eXtender (APEX), and Farm Income and Nutrition Simulator (FARMSIM). The IDSS was applied in Dimbasinia watershed in northern Ghana using irrigation water from shallow groundwater. The watershed has a modest amount of shallow groundwater resources. However, the average annual irrigation water requirement exceeded the average annual shallow groundwater recharge. It was found that the current crop yield in Dimbasinia watershed was only ~40% of the potential crop production. This is mainly related to climate variability, low soil fertility, and land-management practices. For example, application of 50 kg/ha urea and 50 kg/ha DAP doubled maize and sorghum yield from the current farmers’ practices. Better income was obtained when irrigated vegetables/fodder were cultivated in rotation with sorghum as compared to in rotation with maize. Investment in solar pumps paid better dividends and also supplied clean energy. The socio-economic analysis indicated that having irrigated dry season vegetables will improve household nutrition. Since shallow groundwater recharge alone may not provide sufficient water for irrigation in a sustainable manner, surface water may be stored using water-harvesting structures to supplement the groundwater for irrigation. Integrated use of the water resources will also reduce depletion of the shallow groundwater aquifer. We conclude that IDSS is a promising tool to study gaps and constraints as well as upscaling of SSI. 
Keywords:small-scale irrigation; SWAT; APEX; FARMSIM; IDSS; Ghana