The City of Cape Town (CCT) came close to running out of water during the 2015-2017 "Day Zero" drought, which would have had enormous societal and economic impacts. The CCT initiated its "New Water Programme " in earnest in early 2018 to diversify its water supply to improve long-term water security and resilience against future droughts, by implementing alternative bulk water supply options to augment its potable water supply. Three main alternative bulk water supply options were identified, including desalination, water re-use and the abstraction of groundwater from three major aquifer systems that the city has access to, namely the Cenozoic coastal primary Atlantis Aquifer and Cape Flats Aquifer, and the Palaeozoic fractured Table Mountain Group aquifers. The planning and rapid implementation of municipal bulk water supply groundwater schemes under such extreme circumstances, compounded by the hydrological uncertainties associated with contemporary climate change in a region considered highly susceptible to future recurrence of extreme drought conditions, poses several geoethical issues. Because of the great local inequalities of Cape Town society, in which the poorest communities generally suffered most under the drought crisis, a "no-regrets approach" (which is essentially a geoethical approach) was adopted by the CCT. The CCT's response to climate change and the optimisation of scarce resources therefore provides valuable lessons for other cities and municipalities, around South Africa and beyond its borders.
