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MacAllister DJ, Nedaw D, Kebede S, Mkandawire T, Makuluni P, Shaba C, Okullo J, Owor M, Carter R, Chilton J, Casey V, Fallas H, MacDonald AM. Contribution of physical factors to handpump borehole functionality in Africa. Sci Total Environ 2022; 851:158343. [PMID: 36041625 DOI: 10.1016/j.scitotenv.2022.158343] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2022] [Revised: 08/16/2022] [Accepted: 08/23/2022] [Indexed: 06/15/2023]
Abstract
Handpumps are the main water supply for rural communities across sub-Saharan Africa. However, studies show that >25 % of handpumps are non-functional at any time. We present results from a systematic field study of handpump borehole functionality. The study was designed to investigate the contribution of physical factors to functionality outcomes, including; hydrogeology, borehole configuration, and handpump components. To achieve this, we deconstructed and examined 145 handpump boreholes in Ethiopia, Uganda and Malawi. Pumping tests showed that 19 % of boreholes were located in aquifers with transmissivity below the minimum required to sustain a handpump. Water levels, measured during the dry season, had a complex relationship with borehole configuration and transmissivity. The handpump cylinder was <10 m below the water table at 38 % of sites, which increases the risk of the handpump running dry during intensive use and/or in areas of low transmissivity. The water column was <20 m at 23 % of sites and screens were <10 m long at 29 % of sites and often sub-optimally positioned in the borehole. Borehole depth had no clear relationship with functionality. Using multinomial regression and four functionality categories (functional; unreliable; low yield; unreliable and low yield) as dependant variables, we found that transmissivity is a significant risk factor for the classification of handpump boreholes as low yield. The configuration of the borehole (e.g. cylinder position, screen/casing configuration and water column) is a statistically significant risk factor for the classification of handpump boreholes as unreliable. Handpump components were in poor overall condition but rising main pipes were a particular problem with 53 % of galvanised pipes corroded and 82 % of uPVC pipes damaged, with implications for handpump performance. Our study highlights the importance of; understanding aquifer properties, investing in borehole siting, construction (including supervision) and commissioning, and improving the quality of components and maintenance of handpumps.
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Affiliation(s)
| | - D Nedaw
- School of Earth Sciences, University of Addis Ababa, Addis Ababa, Ethiopia
| | - S Kebede
- School of Earth Sciences, University of Addis Ababa, Addis Ababa, Ethiopia; University of KwaZulu Natal, Centre for Water Resources Research, Pietermaritzburg, Private Bag X01, Scottsville, South Africa
| | - T Mkandawire
- University of Malawi, The Polytechnic, Private Bag 303, Blantyre 3, Malawi
| | - P Makuluni
- University of Malawi, The Polytechnic, Private Bag 303, Blantyre 3, Malawi; University of New South Wales, School of Minerals and Energy Resources Engineering, Sydney, Australia
| | - C Shaba
- University of Malawi, Chancellor College, PO Box 280, Zomba, Malawi
| | - J Okullo
- Department of Geology and Petroleum Studies, Makerere University, Kampala, Uganda
| | - M Owor
- Department of Geology and Petroleum Studies, Makerere University, Kampala, Uganda
| | - R Carter
- Richard Carter and Associates Ltd, Second Floor Rear, The Oxlip, 2 Church Street, Ampthill, Bedford, UK
| | - J Chilton
- 16 Nun's Acre, Goring-on-Thames, Reading, UK
| | - V Casey
- WaterAid UK, WaterAid, 6th Floor, 20 Canada Square, London, UK
| | - H Fallas
- British Geological Survey, The Lyell Centre, Edinburgh, UK
| | - A M MacDonald
- British Geological Survey, The Lyell Centre, Edinburgh, UK
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