Feasibility and Efficiency of an Integrated Large-Scale Bhungroo Irrigation Technology in West Mamprusi Sub-Catchment, Ghana

Abstract

Many smallholder farmers are intensifying their production in ecologically harmful ways, necessitating an urgent shift towards sustainable agricultural practices using appropriate local technologies. This study focuses on the feasibility and efficiency of integrated agro-ecological technologies and their impact on socio-economic livelihoods in arid and semi-arid lands, specifically in the West Mamprusi sub-catchment in Ghana. The study evaluates Integrated Bhungroo and Grundfos Lifelink technologies, examining the interoperability and techno-economic aspects of large-scale Bhungroo Irrigation Technology (BIT) deployment. Nine Bhungroos were tested successfully in the West Mamprusi sub-catchment, which served as the field observation site. Using a quasi-experimental design, the study compared responses from Upstream Farming Communities (experimental group) and Downstream Farming Communities (control group) regarding agricultural water adaptation to climatic trends and surface water flow patterns under Bhungroo Irrigation schemes. Field observations revealed that over 95% of the area is underlain by rocks of the Voltaian SuperGroup, with 85% of upstream farmlands consisting of about 80% clay. These materials have low vertical hydraulic conductivities, ranging from 2.56 m/day to 18.27 m/day, leading to waterlogged conditions, especially upstream. Bhungroo technology can be implemented where subsoil strata allow water storage. The highest percentages of waterlogging occur in JAS, with 67% upstream and 48% downstream. Data from BIT pilots indicate that recharge distribution follows the geology, with the highest recharge in areas underlain by Birimian rocks. This suggests a high probability of retention in underground reservoirs for harvesting floodwaters, particularly in the lower catchment area of the West Mamprusi District.