Applying in-situ fluorescence and molecular screening techniques to understand contamination and contributing risk factors in shallow urban groundwaters in sub-Saharan Africa

Shallow hand dug wells and boreholes are particularly important as local sources of water in sub-Saharan Africa. They are also potentially most at risk from anthropogenic contamination. As such, mapping groundwater contamination and understanding the key risk factors remains a priority. The risk of microbial contamination is often evaluated using sanitary risk assessments and characterised using thermotolerant coliforms and faecal streptococci as indicators. This paper evaluates this approach along with novel techniques including molecular pathogen screening and in-situ optical fluorescence for tryptophan (a protein waste water marker), as well as traditional chemical indicators. Groundwater quality sampling and characterisation were done during the wet and dry seasons at 50 sites (including hand dug wells and boreholes) across Kabwe, Zambia. Kabwe is a former mining town in Central province with a history of contamination and a population of around 200,000, which is largely dependent on groundwater for water supply.