Groundwater Irrigation and Small-holder Agriculture:India's Experience and its Implications for Sub-Saharan Africa
International Water Management Institute
This paper argues that making available 3-5 million small-scale, mechanized groundwater irrigation structures can revolutionize small-holder farming in Sub-Saharan Africa. Instead of fancy canal irrigation systems, small-scale groundwater development can quickly improve food and livelihood security for Sass poor and make droughts history without posing any significant environmental threat. Groundwater irrigation using small pumps and boreholes has revolutionized small-holder farming in South Asia. For a long time, it was widely thought that intensive groundwater irrigation is confined to rich alluvial aquifer systems of the Indo-Gangetic basin; as a result, the South Asian experience was thought irrelevant for small-holder agriculture development in Sub-Saharan Africa, which is mostly underlain by a variety of low-yielding hard-rock formations. Hard-rock areas, 65 percent of the Indian land mass below the Vindhyas too have low groundwater yield, unsuitable for large-scale resource development. However, in India, these have experienced a veritable boom in groundwater irrigation which has emerged as the mainstay of its small holder farming livelihoods. The likely reason is that while low-yielding hard rock formations may be unsuitable for producing a large volume of water at a point in space, they are amenable to small-scale development in a dispersed format. The question is: if low-yielding hard rock formations have served small holders in India well, why should they not be developed for supplemental irrigation in Sub-Saharan Africa which has a comparable rainfall regime. The stock response is: the ?precautionary principle?; that Sub-Saharan Africa will face the same problems of over-exploitation of the resource as is increasingly evident in hard rock areas of India. We suggest this is unlikely to be the case; that the pressure on groundwater resources in India is determined by the high ratio of farming to total areas (at 50 percent or more) which in turn is the outcome of high population density. Sub-Saharan Africa has less than 5 percent of its landmass under plough; moreover, small-holder farming in tiny pockets is spread thin over a vast terrain resulting in a moderate non-point demand for groundwater. If anything, SSA?s groundwater resource will come under threat from municipalities or large-scale commercial farmers that represent high point-demand. Small-scale groundwater development would be an ideal, low-cost alternative for quickly uplifting small-holder agriculture in SSA, where developing canal irrigation is expensive because of low population density.