Papua New Guinea, Equatorial Guinea and Angola top the list of nations with the lowest percentage of households with access to clean water. In Papua New Guinea, for example, where 60% of the country’s 7.3 million population is without safe water, the poorest of the poor pay as much as 54% of their daily earnings for about 13 gallons of water from a delivery service, according to the report. Those 13 gallons, which is what the World Health Organization recommends as the minimum daily amount to meet basic needs, cost $2.60.