Microbiological risks of recycling urban stormwater via aquifers for various uses in Adelaide, Australia

This study investigates the potential for an aquifer to provide treatment of stormwater in addition to engineered treatment for the safe use of recovered water for drinking and non-drinking supplies. A brackish limestone aquifer was investigated as a treatment barrier when assessing microbial health-based targets of stormwater harvesting systems. Aquifer treatment was assessed based on pathogen inactivation and attachment to the aquifer sediments. The results showed that the health-based targets for different end uses including open space irrigation, domestic and industrial non-potable uses and drinking water could be met with additional treatment. The aquifer was estimated to have potential for ~4 log₁₀ removal based on inactivation studies and attachment to the aquifer.