Despite there being large
amounts of groundwater (approximately 0.66 million km3 across Africa (MacDonald et al. 2012)), we still need to be cautious about how much we can
abstract sustainably, because over-abstraction of groundwater supplies can have
detrimental social, economic and environmental impacts (Pavelic et al. 2013). Not only can over
abstraction lead to depletion of groundwater reserves, it can also have other
consequences such as land subsidence, saline intrusion and increasing costs of
pumping, to name a few (Ogunba 2012, European Environment Agency 2016). Consequently,
management is very important.
Agricultural irrigation is a
major cause of groundwater over-abstraction (European
Environment Agency 2016) and managing this is very difficult with the current
trends in African farming leaning towards small-holder farming. Due to increasing access to low cost pumps and
climatic variability, “groundwater irrigation for small holder farmers in SSA
is growing in extent and importance” (Villholth 2013: 369). A higher number of
individual users makes it more difficult to impose and enforce groundwater
restrictions and/or monitoring to ensure sustainable abstraction (Knuppe 2011).
Small-scale, rural farmers are also more likely to have conflict with
management regulation than larger irrigation companies and projects, often
holding traditional attitudes and expertise (Knuppe 2011). Couple this with a
rather patchy and inadequate understanding of aquifer levels and behaviour, and
it makes for rather difficult management.
