Seeking a circular economy of human nutrition: sewage farming in four Australian cities

In an era of increasing enthusiasm for recycling and water conservation, we trace the history of urban Australian efforts to re-use the plant nutrients in human excrement to produce food. From the widespread use of nightsoil on market gardens to experiments with sewage farming in multiple Australian cities, only Melbourne has maintained nutrient re-use through sewage farming. Where other cities had insufficient political support to enable the expenditure, planning and technical adaptation needed to productively use increasing sewage output, Melbourne, located on an enclosed bay unsuitable for the expedient disposal of raw sewage, had institutional leadership that saw sufficient investment for the sewage farm to become a socially accepted long-term success. The legacies of these histories persist into the present.