Abstract
Dan Lapworth, Jim Wright and Steve Pedley are working to find out how to provide safe water for poor people living in African cities. Dan co-ordinated a team of Zambian and UK scientists to carry out a groundwater quality survey across Kabwe in 2013-14. This revealed that shallow household supplies (less than 10m underground) were highly contaminated throughout the year with faecal bacteria and nitrate, as well as elevated concentrations of the commonly-used insect repellent DEET. As part of the work Dan is leading, the team tested a field sensor designed to measure a protein called tryptophan, an indicator of waste-water contamination, particularly with faecal matter. Jim co-ordinated a follow-up survey by the same team to see what had changed over the past decade in Kisumu, Kenya's third largest city. As well as recording hazards and testing wells, the team also interviewed well owners and those using the groundwater. The survey showed that the groundwater from the wells is still heavily contaminated with faecal bacteria.