Abstract
There is no common understanding of the minimum per capita fresh water requirement for human health and economic and social development. Existing estimates vary between 20 litres and 4,654 litres per capita per day, however, these estimates are methodologically problematic as they consider only human consumptive and hygiene needs, or they consider economic needs but not the effects of trade. Reconsidering the components of a minimum water requirement estimate for human health and for economic and social development suggests that a country requires a minimum of 135 litres per person per day. With all countries except Kuwait having much greater water resources than this, water scarcity alone need not hinder development. Given the steadily decreasing cost of desalination together with the relatively small amount of water required per capita to permit social and economic development, desalination should be affordable where necessary for all but the very least economically developed countries where local naturally occurring freshwater resources are insufficient and saline water is available.