Mapping groundwater quality degradation beneath growing rural towns in Sub-Saharan Africa

Novel methods for understanding contamination and risk factors in shallow urban groundwaters

The problem: Shallow hand dug wells and boreholes in urban areas are potentially at high risk of contamination. Mapping of groundwater contamination and understanding the key risk factors remains a priority.

The approach: In-situ optical fluorescence for tryptophan (a protein waste water marker) and molecular pathogen screening (qPCR), alongside conventional measurements and assessments for groundwater quality surveys during the wet and dry seasons at 50 sites.

Key findings: High groundwater vulnerability in shallow wells irrespective of land use; overall degradation of water quality during the wet season; nitrate contamination in some deeper sites; pumping induced connectivity between shallow and deep GW based on age tracers and organic contaminants; impact of mine waste in some shallow wells in close proximity to waste.

Where? Zambia

Consortium grant? No.

Principal Investigator: Dan Lapworth (British Geological Survey, BGS)

Research Team:

• Marianne Stuart, British Geological Survey
• James Sorensen, British Geological Survey
• Daniel Nkhuwa, University of Zambia
• Moshood Tijani, University of Ibadan
• Daniel Read, Centre for Ecology & Hydrology
• Stephen Pedley, University of Surrey

Research Organisations:

• British Geological Survey (BGS) – Grant NE/L002078/1
• University of Zambia (UZ)
• University of Ibadan (UI)
• Centre for Ecology & Hydrology (CEH)
• University of Surrey (US)

Find out more:

• BGS Research highlight:  Real-time monitoring of faecally contaminated drinking water (4 Dec 2020)

• Lapworth, D.J.; Stuart, M.E.; Pedley, S.; Nkhuwa, D.C.W.; Tijani, M.N.. 2017 A review of urban groundwater use and water quality challenges in Sub-Saharan Africa. Nottingham, UK, British Geological Survey, 133pp. (OR/17/056) (Unpublished)
• “Tryptophan-like fluorescence- an effective real-time indicator of faecal contamination in drinking water” (2016) James Sorensen
• PDF summary
  • Mapping groundwater quality degradation beneath growing rural towns in SSA
  • Cartographier la dégradation de la qualité des eaux souterraines des bourgs ruraux en expansion en Afrique sub-Saharienne
• “Urban Groundwater Quality and Quantity in Sub-Saharan Africa: A Case for Lusaka, Zambia” by Dr Daniel Nkhuwa at “Urban Groundwater Quality and Quantity in Sub-Saharan Africa: A Case for Lusaka, Zambia” by Dr Daniel Nkuwa
• Sorensen J, D.J. Lapworth,  D. S. Read, D.C.W. Nkhuwa,  R.A. Bell, M. Chibesa (2015) “Tracing enteric pathogen contamination in sub-Saharan African groundwater” Science of The Total Environment 538:888-895 · September 2015, DOI: 10.1016/j.scitotenv.2015.08.119
• “Using emerging contaminants to trace rapid recharge pathways in urban groundwater: an example from Kabwe, Zambia”, Dan Lapworth, James Sorensen, Daniel Nkhuwa (presentation)
• “Tracking pathways for pathogen contamination in urban groundwater supplies in Africa: novel application of qPCR techniques”, Dan Lapworth, James Sorensen, Dan Read, Steve Pedley,Daniel Nkhuwa and Rachel Bell (presentation)
• “Using emerging contaminants to trace rapid recharge pathways in urban groundwater: an example from Kabwe, Zambia”, Dan Lapworth, James Sorensen, Daniel Nkhuwa (presentation)
• “Real-time inference of thermotolerant coliforms in groundwater”, James Sorensen (a), Dan Lapworth, Ben Marchant, Daniel Nkhuwa and Steve Pedley
• Dan Lapworth presents in the RWSN-UPGro webinar Groundwater Resources and Supplies in Africa 24 February 2015
• Dan Lapworth presents poster at 41st IAH Congress, Marrakech, September 2014
• Sorensen, J. P. R.D.J. Lapworth,D.C.W. Nkhuwa, M.E. Stuart, D.C. Gooddy,R.A. Bell, Chirwab, M. Chirwa, J. Kabika, M. Liemisa, M. Chibesa, S. Pedley “Emerging contaminants in urban groundwater sources in Africa” Water Research – In Press
• Lapworth D. J. , J. Sorensen, S. Pedley, D. C. W. Nkhuwa, D. Read, M. Chibesa, M. Chirwa, R. Bell, M. Liemisa, M. Stuart1, and J. Kabika (2014) “Applying in-situ fluorescence and molecular screening techniques to understand contamination and contributing risk factors in shallow urban groundwaters in sub-Saharan Africa” Poster submission to 41st IAH congress
• SORENSEN J., S. PEDLEY, D. READ, M. CHIBESA, M. CHIRWA, R. BELL, D. NKHUWA, M. LIEMISA, M. STUART, D.J. LAPWORTH (2014) “Characterising pathogen contamination in urban groundwater in Kabwe, Zambia: a comparative study using multiple pollution indicators and contributing risk factors” Abstract submission to 41st IAH congress
• Lapworth, D., J Wright and S. Pedley (2014) A tale of two cities: How can we provide safe water for poor people living in African cities? Planet Earth Magazine Winter 2014, p 22-23, NERC, London, UK
• Sorensen J, D.J. Lapworth, B.P. Marchant, D.C.W. Nkhuwa, S. Pedley, M.E. Stuart, R.A. Bell, M. Chirwa, J. Kabika, M. Liemisa, M. Chibesa (2015) “In-situ tryptophan-like fluorescence: A real-time indicator of faecal contamination in drinking water supplies” Water Research, Volume 81, 15 September 2015, Pages 38–46