A national border-based assessment of Malawi’s transboundary aquifer units: Towards achieving sustainable development goal 6.5.2

A methodology to identify vulnerable transboundary aquifer hotspots for multi-scale groundwater management

“…Fuzzy overlay allows the user to overlay the various Figure 1. Transboundary aquifers shared between Malawi and its neighbours in the wider SADC (adapted from Fraser et al, 2020Fraser et al, , 2018.…”

“…A recent study that took a detailed and national-border-based approach to transboundary aquifer assessments in Malawi identified 38 transboundary aquifer units shared between Malawi and its neighbours, in contrast to a previous estimate of three (Fraser et al, 2020(Fraser et al, , 2018. It is likely that other countries, like Malawi, have many more transboundary aquifers than previously thought.…”

“…Three transboundary aquifers in Malawi were first identified by the Global Environment Facility's Transboundary Waters Assessment Programme, which aimed to provide the first global-scale assessment of all transboundary waters (Fraser et al, 2018;ILEC et al, 2016). More recently, Fraser et al (2020) increased this number to 38 by including smaller, more locally significant aquifers in their assessment. Figure 1 illustrates the current understanding of transboundary aquifers shared between Malawi and its neighbours.…”

“…National-border-based assessments (Fraser et al, 2020) generate data that allow governments to evaluate their transboundary aquifers in detail. Hotspot analysis of these identified transboundary aquifers, as conducted in this study, highlight which aquifers require immediate attention and at what scale.…”

“…Both surface waters and groundwater can be transboundary, meaning that rivers, lakes and aquifers have the ability to store and transmit water across a state or border (Fraser et al, 2020). Whereas transboundary surface waters have been extensively studied worldwide, transboundary aquifers have received much less attention (Rivera & Candela, 2018).…”