We speak to Harriet Bulkeley (HB) and Patience Mguni (PM), two of the Guest Editors of the PLOS Climate and PLOS Water‘s…
By Kerstin Danert
In sub-Saharan Africa (SSA) today, about half a billion people, equivalent to 50% of the population rely on protected and unprotected groundwater point sources. This means springs and hand dug wells alongside boreholes or tubewells. Many piped networks also use groundwater, but reliable data on this for SSA is lacking. Population growth, anticipated increased irrigation and economic development means that the use of groundwater in SSA will grow tremendously in the future. Further, with the increase in rainfall variability that is expected in SSA due to climate change, sustainable groundwater sources will be evermore important in supporting resilience.
Handpumps have revolutionised access to safe, reliable water supplies in low-income countries, particularly in rural areas. They 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). The research estimates that there are between 0.5 and 1.3 million handpumps in use in SSA. It is worth noting that an estimated 23% of the SSA population (about 230 million people) still rely on unsafe and distant water sources and many could benefit from a handpump. At least for a generation, if not much longer, handpumps are here to stay.
Despite their merits, much criticism has been directed to 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 . 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 handpump breaks down for a very specific technical reason (such as the breakage of the chain, an O-ring failing or corroded riser pipes). However, 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.
The ‘Stop the Rot’ research notes the sizeable drop in handpump functionality in the first one to two years after installation. This is a common occurrence, and represents a premature technical failure. In other words, 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 This phenomenon has been known about since the 1980s . However, in at least 20 SSA countries, there is evidence that rapid corrosion remains an issue. 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.
And so, what does the research recommend? It firstly proposes the establishment of an action group of key organisations involved in Rural Water Supplies in SSA, and handpumps in particular, to 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, and that this 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.
Finally, there are plenty of other industries that are consistently able to ensure that high-quality products reach the market. What can be learned from them so that handpump users in SSA are able to use a handpump with quality parts, and which will not be subject to rapid corrosion?
The full set of research reports can be downloaded here. From the end April 2022, they will also be available in French.
Dr Kerstin Danert is a water specialist, researcher and facilitator with over 20 years of experience of rural water supplies in Sub-Saharan Africa. She has worked in close collaboration with the Rural Water Supply Network (RWSN) since 2005. In January 2020 she launched Ask for Water GmbH.
1. RWSN Executive Steering Committee. Myths of the Rural Water Supply Sector. RWSN Perspective No 4, RWSN , St Gallen, Switzerland. 2010. Available from: https://www.rural-water-supply.net/en/resources/details/226
2. Foster T, Furey S, Banks B and Willets J. Functionality of handpump water supplies: A review of data from sub-Saharan Africa and the Asia-Pacific region. International Journal of Water Resources Development 2019; 36: 855–869. doi: 10.1080/07900627.2018.1543117
3. Langenegger O. Groundwater Quality – An Important Factor for Selecting Handpumps. Developments in Water Science 1989; 39: 531–541. doi: 10.1016/S0167-5648(08)70561-6