Currently, about half a billion people, in sub-Saharan Africa (SSA), equivalent to half of the population, rely on protected and unprotected groundwater point sources for their main drinking water supplies. With the expected increases in rainfall variability due to climate change, sustainable groundwater sources will be evermore important in supporting resilience in the future.
Access to safe, reliable water supplies in low-income countries, particularly in rural areas has been improved through handpumps, which provide a viable alternative to contaminated surface water, open wells and unprotected springs.
Three new reports from the ‘Stop the Rot’ initiative published in March 2022 examine handpump reliance, rapid corrosion, the quality of handpump components and supply chains in SSA. The research looked specifically at the main public domain handpumps – the India Mark Pump, and the Afridev Pump, and also drew on learnings from the Zimbabwe Bush Pump.
Using the most recent data published by the World Health Organization (WHO) and the United Nations Children’s Fund (UNICEF) through the Joint Monitoring Programme (JMP), the ‘Stop the Rot’ research estimates that almost 200 million people in SSA (18.5% of the total population) rely on handpumps to provide them with their main drinking water supply (Figure below). Further, an estimated 700,000 handpumps are in use in SSA. Meanwhile, 23% of the SSA population still rely on unsafe and distant water sources, of which many could benefit from a handpump. At least for a generation, if not much longer, handpumps are here to stay.
Despite their merits, criticism has been directed towards handpumps. Limited ability to transport large quantities of water, coupled with a lack of storage capacity at the home, means that water from handpumps is usually fetched on a daily basis. Handpumps have also made the headlines: in 2010, an estimated two out of three handpumps in SSA were working; a decade later it was estimated to have only improved to three out of four.
A handpump breaks down for a specific technical reason (such as the breakage of the chain, an O-ring failing or corroded riser pipes), but its repair depends on the ability of the users, often a community, to raise funds, organise a mechanic and source spare parts. In turn, these depend on other factors within the locality and country, including the available services support mechanisms by governments, NGOs and the private sector. When water services fail, there are negative impacts on health and other human development gains, not to mention the burden on users of finding alternative sources. These may be distant, overcrowded, or contaminated.
A sizeable drop in handpump functionality in the first one to two years after installation is a common occurrence, and represents a premature technical failure. Something went wrong with the engineering – such as the borehole siting, design and/or construction, pump quality or installation, or the pump use – or there was vandalism or theft. Alternatively, the installation may have been rejected by the users from the outset due to its location, or the appearance or taste of the water.
The series of three ‘Stop the Rot’ publications draw attention to rapid handpump corrosion, whereby aggressive groundwater destroys the galvanising layer and so galvanised iron (or poor-quality stainless steel) riser pipes and pump rods essentially rot in the ground at a very fast rate (see Figures below). The term ‘aggressive’ refers to the ability of the groundwater to corrode, disintegrate and deteriorate materials it is in contact with, and includes, but is not limited to acidity is one type of pump.
This phenomenon has been known about since the 1980s. However, this new study finds evidence of rapid corrosion in in at least 20 SSA countries. A related problem is the quality of handpump components. The research draws attention to long supply chains from manufacture to installation, shows that component quality is not consistent and that there is limited guidance on quality assurance, and that in many cases, procedures are lacking.
The study proposes the establishment of an action group of key organisations involved in Rural Water Supplies in SSA, and handpumps in particular, to join hands and take a lead in tackling the challenge. Many actions are needed at international, national and local level. These including raising awareness of the extent that handpumps are used in SSA, which will continue into the future. There is need for sensitization regarding the ongoing rapid corrosion issue, and how it can be addressed alongside incentives for doing so. There is also the need to invest in updating handpump specifications, improving quality assurance mechanisms and strengthening procurement procedures and practice.
The full set of research reports can be downloaded in English and French. There is also a 20 minute presentation available here, and a recording of the RWSN webinar involving the presentation and discussions is available here.
This is a shortened version of a blog that was originally published by PLOS Latitude.