Dhinakaran Govindasamy

Factors Influencing the Functionality of Handpump Boreholes in Sub-Saharan Africa

Globally, three out of ten people do not have access to safedrinking water, and sub-Saharan Africa (SSA) houses close to half of them. Groundwater is the primary source of safe drinking water in rural SSA, with handpump borehole (HPB) being the most widely used groundwater extraction method.  One of the issues regarding the use of HPB in SSA is that,at any time, only about 70% of them are functional. This study analyses the physical factors affecting the functionality of HPB in rural areas in 3 countries in the SSAregion, namely Ethiopia, Uganda and Malawi, using thedata collected by the Hidden Crisis ResearchProject team. While numerous studies have been done in this field, this paper assesses the problem from a systems perspective using a Bayesian Network(BN). Analyses were done by testing different scenarioson the BNto observe the relationshipbetween the factorsandHPB functionality. Subsequently, the BN model was used to assess the effectiveness of existing policies, guidelines and practices on HPB design and operations.Analyses were also done on an enhanced BN model, which included other factors and relationships. The analysis shows that only around 20% of the HPBs in rural SSA are ‘Fully Functional’, and even in the best case, theprobabilityof the HPBsbeing ‘Fully Functional’is only 64.8%.Additionally,‘broken/cracked/damagedhandpump parts’, ‘insufficient cylinder depth’and ‘borehole design’are the top three underlying factors affecting HPB functionality.Moreover, the analysis validatesthe effectivenessof a few policies, like focusingresources for the maintenance of HPBs, and challenges other requirements, like the minimum distance from latrines. Additional assessment that includes other factors like reliability shows that onlyaround 13% of the HPBs in the region may be‘Fully Functional and Reliable’, and in the best case around 30%. In summary, analysis using a Bayesian Network provides an opportunity to understand the HPB functionality issue holistically and can be used as a tool to assess the effectiveness of certain policies, guidelines and practices, by establishing the extent of the influence of physical factors.